Publications by authors named "Manohar L Garg"

116 Publications

Dietary supplementation with docosahexaenoic acid rich fish oil increases circulating levels of testosterone in overweight and obese men.

Prostaglandins Leukot Essent Fatty Acids 2020 12 12;163:102204. Epub 2020 Nov 12.

Nutraceuticals Research Program, School of Biomedical Sciences & Pharmacy, Newcastle, New South Wales, Australia; Priority Research Centre for Physical Activity and Nutrition, Newcastle, New South Wales, Australia; Riddet Institute, Massey University, Palmerston North, New Zealand; Corresponding author: 305C Medical Sciences Building, University of Newcastle, Callaghan, NSW - 2308, AUSTRALIA, Tel.: +61 2 4921 5647.. Electronic address:

Pre-clinical evidence suggests that omega-3 (n-3) polyunsaturated fatty acids (PUFAs), in particular, docosahexaenoic acid (DHA) have been shown to affect testosterone synthesis in males. This study is a secondary analysis of a randomized controlled trial which determined the effect of a DHA-enriched fish oil supplement on insulin resistance. The aim of the current study was to determine whether testosterone levels change in response to a DHA-enriched fish oil intervention. Overweight and obese men and women without diabetes were recruited to the study. Participants were stratified by sex and randomly allocated to intervention (860 mg DHA + 120 g EPA/day; FO) or an isocaloric control (corn oil; CO) for 12 weeks. A fasted blood sample was collected pre- and post-intervention. Fatty acid composition of erythrocyte membranes was measured using gas chromatography. Total testosterone and metabolic parameters were measured by an accredited commercial pathology laboratory. Sixty-one participants (CO/FO: n = 29/32) were included in the current analysis (male: n = 22, 36.07%).  DHA-enriched fish oil supplementation increased total testosterone levels in males after adjusting for baseline levels, age and BMI. There was no treatment effect in females. Changes in testosterone levels in males were positively associated with changes to omega-3 PUFAs EPA and DHA and inversely correlated with omega-6 PUFA, arachidonic acid and dihomo-gamma-linolenic acid content in erythrocyte membranes, and was associated with beneficial changes to fasting insulin and HOMA-IR across the course of the study. DHA-enriched fish oil supplementation increases testosterone levels in overweight and obese men. Further research is warranted to substantiate these findings with a larger sample size and a longer follow-up period.
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http://dx.doi.org/10.1016/j.plefa.2020.102204DOI Listing
December 2020

Postprandial lipaemia following consumption of a meal enriched with medium chain saturated and/or long chain omega-3 polyunsaturated fatty acids. A randomised cross-over study.

Clin Nutr 2021 Feb 1;40(2):420-427. Epub 2020 Jul 1.

Nutraceuticals Research Program, School of Biomedical Sciences & Pharmacy, 305C Medical Sciences Building, University of Newcastle, Callaghan, NSW, 2308, Australia; Riddet Institute, Massey University, Palmerston North, New Zealand. Electronic address:

Background & Aims: Postprandial lipaemic response has emerged as a risk factor for cardiovascular disease. Dietary fats such as medium-chain saturated fatty acids (MCSFA) and long-chain omega-3 polyunsaturated fatty acids (LCn-3PUFA) are known to reduce postprandial lipaemic responses. The combination of the two could potentially have complementary and/or synergistic effects for optimising cardiovascular health. This study aims to investigate the effects of MCSFA (coconut oil) with or without LCn-3PUFA (fish oil) inclusion in the test meal on postprandial blood lipids in healthy adults.

Methods: In a randomised, double-blinded, placebo-controlled, 2 × 2 factorial cross-over study, participants (n = 15) were randomised to receive four standardised isocaloric test meals. Test meals include: placebo [PL, containing no fish oil (0 g EPA & DHA) or coconut oil (0 g MCSFA)], fish oil [FO, 6 g fish oil (3.85 g EPA & DHA), containing no coconut oil (0 g MCSFA)], coconut oil [CO, 18.65 g coconut oil (15 g MCSFA), containing no fish oil (0 g EPA & DHA)] and coconut oil + fish oil [COFO, 18.65 g coconut oil (15 g MCSFA) + 6 g fish oil (3.85 g EPA & DHA)]; all providing a total fat content of 33.5 g. Participants received all four treatments on four separate test days with at least 3 days washout in between. Blood parameters were measured by finger pricks at 7 timepoints between 0 and 300min. The primary outcome of this study was the change in postprandial triglycerides (TG) concentrations with secondary outcomes as total cholesterol, high-density lipoprotein cholesterol and blood glucose concentrations.

Results: TG area under the curve (AUC) (mmol/L/min) was significantly lower for FO (383.67, p = 0.0125) and COFO (299.12, p = 0.0186) in comparison to PL (409.17) only. TG incremental area under the curve (iAUC) (mmol/L/min) was significantly lower with COFO (59.67) in comparison to CO (99.86), (p = 0.0480). Compared to PL, the change in absolute TG concentrations (mmol/L) from baseline to post TG peak time (180min) after FO were significantly less at 240min (0.39 vs 0.15), 270min (0.2 vs 0.1), and 300min (0.28 vs 0.06), and after COFO was significantly less at 300min (0.28 vs 0.16) (p < 0.05). No significant differences in postprandial AUC and iAUC for any other blood parameters were reported.

Conclusions: Our study demonstrated that LCn-3PUFA with or without MCSFA but not MCSFA alone are effective in reducing postprandial TG in healthy individuals.
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http://dx.doi.org/10.1016/j.clnu.2020.06.027DOI Listing
February 2021

Docosahexaenoic Acid-Rich Fish Oil Supplementation Reduces Kinase Associated with Insulin Resistance in Overweight and Obese Midlife Adults.

Nutrients 2020 May 30;12(6). Epub 2020 May 30.

Nutraceuticals Research Program, School of Biomedical Sciences & Pharmacy, University of Newcastle, Callaghan NSW 2308, Australia.

Targeting kinases linked to insulin resistance (IR) and inflammation may help in reducing the risk of type 2 diabetes (T2D) and Alzheimer's disease (AD) in its early stages. This study aimed to determine whether DHA-rich fish oil supplementation reduces glycogen synthase kinase (GSK-3), which is linked to both IR and AD. Baseline and post-intervention plasma samples from 58 adults with abdominal obesity (Age: 51.7 ± 1.7 years, BMI: 31.9 ± 0.8 kg/m) were analysed for outcome measures. Participants were allocated to 2 g DHA-rich fish oil capsules (860 mg DHA + 120 mg EPA) (n = 31) or placebo capsules (n = 27) per day for 12 weeks. Compared to placebo, DHA-rich fish oil significantly reduced GSK-3β by -2.3 ± 0.3 ng/mL. An inverse correlation ( < 0.05) was found between baseline insulin and IR and their changes following intervention only in participants with C-reactive protein levels higher than 2.4 mg/L. DHA-rich fish oil reduces GSK-3 and IR, suggesting a potential role of long-chain omega-3 polyunsaturated fatty acids (LCn-3PUFA) in ameliorating AD risk.
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http://dx.doi.org/10.3390/nu12061612DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7352487PMC
May 2020

Association between Obesity and Omega-3 Status in Healthy Young Women.

Nutrients 2020 May 20;12(5). Epub 2020 May 20.

Faculty of Medicine and Health, School of Health Sciences, The University of Sydney, Sydney, NSW 2006, Australia.

Omega-3 polyunsaturated fatty acids (n-3 PUFAs) are essential for healthy development and protect against metabolic disease. However, individuals with obesity may be pre-disposed to experiencing lower n-3 PUFA status than normal-weight individuals. This cross-sectional study examined the relationship between the omega-3 index (O3I), body mass index (BMI) and dietary intake in healthy young women (n = 300; age = 18-35 y), a group not previously focused on. Intake was adjusted for energy using the residuals method, and associations were explored using independent -tests and Pearson's correlations. Participants with obesity were found to have significantly lower O3I than normal-weight participants ( < 0.0001); however, no significant differences were observed in mean n-3 PUFA intakes. Even so, energy-adjusted intakes of n-3 PUFAs, with the exception of alpha-linolenic acid, were significantly correlated with O3I. This study demonstrates that O3I is influenced by both BMI and diet in young women; however the relationship between these two variables may be complex. Current intakes of n-3 PUFA observed in young women may not be effective in achieving target O3I levels in those with obesity, and further research is needed to find effective ways of improving n-3 PUFA status in a group already at increased risk of metabolic disease.
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http://dx.doi.org/10.3390/nu12051480DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7284478PMC
May 2020

GlucoTRIG: a novel tool to determine the nutritional quality of foods and meals in general population.

Lipids Health Dis 2020 May 4;19(1):83. Epub 2020 May 4.

Nutraceuticals Research Program, School of Biomedical Sciences & Pharmacy, University of Newcastle, Callaghan, NSW, Australia.

Background: This study aimed to develop a novel criterion, GlucoTRIG, to rank meals for healthiness, that considers both glycaemic (serum insulin) and lipaemic (serum triglycerides) responses.

Methods: Healthy volunteers (n = 10) were recruited with the aim of deriving a standard GlucoTRIG value for a reference meal. Volunteers consumed the reference meal (2 regular slices of wholemeal bread; 250 mL chocolate flavoured milk; 7 g butter and 11 g peanut butter) comprising of carbohydrate, fat and protein (41, 40 and 16% energy respectively) on three different occasions with a minimum washout period of 3 days. The GlucoTRIG value was determined as the difference between the product of insulin and triglyceride obtained from venous blood samples at baseline and the product of insulin and triglyceride at 180 min.

Results: There were no significant differences in the participants' dietary intakes and their metabolic parameters between three visits (P > 0.005). The GlucoTRIG value obtained from three mean values of the reference meal was found to be 19 ± 3.5. There were no significant (P = 0.2303) differences observed between the GlucoTRIG values for the three visits.

Conclusion: GlucoTRIG, consisting of both glycaemic and lipaemic responses, may be a physiologically relevant tool to rank foods and meals for reducing the risk of metabolic diseases.

Trial Registration: ACTRN12619000973112.
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http://dx.doi.org/10.1186/s12944-020-01268-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7199359PMC
May 2020

Dietary Supplementation with Curcumin Reduce Circulating Levels of Glycogen Synthase Kinase-3β and Islet Amyloid Polypeptide in Adults with High Risk of Type 2 Diabetes and Alzheimer's Disease.

Nutrients 2020 Apr 9;12(4). Epub 2020 Apr 9.

Nutraceuticals Research Program, School of Biomedical Sciences & Pharmacy, University of Newcastle, Callaghan, NSW 2308, Australia.

Dietary supplementation with curcumin has been previously reported to have beneficial effects in people with insulin resistance, type 2 diabetes (T2D) and Alzheimer's disease (AD). This study investigated the effects of dietary supplementation with curcumin on key peptides implicated in insulin resistance in individuals with high risk of developing T2D. Plasma samples from participants recruited for a randomised controlled trial with curcumin (180 mg/day) for 12 weeks were analysed for circulating glycogen synthase kinase-3 β (GSK-3β) and islet amyloid polypeptide (IAPP). Outcome measures were determined using ELISA kits. The homeostasis model for assessment of insulin resistance (HOMA-IR) was measured as parameters of glycaemic control. Curcumin supplementation significantly reduced circulating GSK-3β (-2.4 ± 0.4 ng/mL vs. -0.3 ± 0.6, = 0.0068) and IAPP (-2.0 ± 0.7 ng/mL vs. 0.4 ± 0.6, = 0.0163) levels compared with the placebo group. Curcumin supplementation significantly reduced insulin resistance (-0.3 ± 0.1 vs. 0.01 ± 0.05, = 0.0142) compared with placebo group. Dietary supplementation with curcumin reduced circulating levels of IAPP and GSK-3β, thus suggesting a novel mechanism through which curcumin could potentially be used for alleviating insulin resistance related markers for reducing the risk of T2D and AD.
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http://dx.doi.org/10.3390/nu12041032DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7230780PMC
April 2020

Long-chain omega-3 polyunsaturated fatty acids and cognitive decline in non-demented adults: a systematic review and meta-analysis.

Nutr Rev 2020 07;78(7):563-578

Nutraceuticals Research Program, School of Biomedical Sciences and Pharmacy.

Context: Long-chain omega-3 polyunsaturated fatty acids (LCn-3PUFAs) are widely considered as nootropic agents that may be beneficial in reversing cognitive impairment.

Objective: The present systematic review of randomized controlled trials was conducted to determine the changes in cognitive function after intervention with LCn-3PUFA supplementation in non-demented adults, including those with mild cognitive impairment.

Data Sources: Five databases (MEDLINE, CINAHL, Scopus, EMBASE, and the Cochrane Library) were searched systematically along with reference lists of selected articles.

Study Selection: Studies were eligible for inclusion if they measured the effect of LCn-3PUFA supplementation on cognition in non-demented adults.

Data Extraction: A total of 787 records were screened, of which 25 studies were eligible for inclusion. Treatment effects were summarized as global cognitive function for primary outcome and measured using the Mini-Mental State Examination and individual cognitive domains for secondary outcome. The pooled effect sizes were estimated using Hedge's g and random-effects modeling.

Data Analysis: Results from randomized controlled trials indicate that LCn-3PUFAs have no effect on global cognitive function (Hedge's g = 0.02; 95% confidence interval, -0.12 to 0.154), and among the specific cognitive domains, only memory function showed a mild benefit (Hedge's g = 0.31; P = 0.003; z = 2.945).

Conclusion: The existing literature suggests that LCn-3PUFA supplementation could provide a mild benefit in improving memory function in non-demented older adults.

Systematic Review Registration: PROSPERO registration no. CRD42017078664.
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http://dx.doi.org/10.1093/nutrit/nuz073DOI Listing
July 2020

Omega-3 polyunsaturated fatty acids status and cognitive function in young women.

Lipids Health Dis 2019 Nov 6;18(1):194. Epub 2019 Nov 6.

Faculty of Health Sciences, Discipline of Exercise and Sport Science, The University of Sydney, PO Box 170, Lidcombe, NSW, 1825, Australia.

Background: Research indicates that low omega-3 polyunsaturated fatty acid (n-3 PUFA) may be associated with decreased cognitive function. This study examined the association between n-3 PUFA status and cognitive function in young Australian women.

Methods: This was a secondary outcome analysis of a cross-sectional study that recruited 300 healthy women (18-35 y) of normal weight (NW: BMI 18.5-24.9 kg/m) or obese weight (OB: BMI ≥30.0 kg/m). Participants completed a computer-based cognition testing battery (IntegNeuro™) evaluating the domains of impulsivity, attention, information processing, memory and executive function. The Omega-3 Index (O3I) was used to determine n-3 PUFA status (percentage of EPA (20:5n-3) plus DHA (22:6n3) in the red cell membrane) and the participants were divided into O3I tertile groups: T1 < 5.47%, T2 = 5.47-6.75%, T3 > 6.75%. Potential confounding factors of BMI, inflammatory status (C-reactive Protein), physical activity (total MET-min/wk), alpha1-acid glycoprotein, serum ferritin and hemoglobin, were assessed. Data reported as z-scores (mean ± SD), analyses via ANOVA and ANCOVA.

Results: Two hundred ninety-nine women (26.9 ± 5.4 y) completed the study (O3I data, n = 288). The ANOVA showed no overall group differences but a significant group × cognition domain interaction (p < 0.01). Post hoc tests showed that participants in the low O3I tertile group scored significantly lower on attention than the middle group (p = 0.01; ES = 0.45 [0.15-0.74]), while the difference with the high group was borderline significant (p = 0.052; ES = 0.38 [0.09-0.68]). After confounder adjustments, the low group had lower attention scores than both the middle (p = 0.01) and high (p = 0.048) groups. These findings were supported by univariate analyses which found significant group differences for the attention domain only (p = 0.004).

Conclusions: Cognitive function in the attention domain was lower in women with lower O3I, but still within normal range. This reduced but normal level of cognition potentially provides a lower baseline from which cognition would decline with age. Further investigation of individuals with low n-3 PUFA status is warranted.
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http://dx.doi.org/10.1186/s12944-019-1143-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6836340PMC
November 2019

Is weight status associated with peripheral levels of oxytocin? A pilot study in healthy women.

Physiol Behav 2019 12 17;212:112684. Epub 2019 Oct 17.

Nutrition and Dietetics, School of Health Sciences, Faculty of Health and Medicine, University of Newcastle, Callaghan NSW 2308, Australia; Priority Research Centre for Physical Activity and Nutrition, University of Newcastle, Callaghan NSW 2308, Australia. Electronic address:

The neuropeptide oxytocin is best known for its role during parturition and the milk-let down reflex. Recent evidence identifies a role for oxytocin in eating behaviour. After oxytocin administration, caloric intake is reduced with stronger inhibitory effects in individuals with obesity. Whether the experience of visual food cues affects secretion or circulating levels of oxytocin is unknown. This pilot study had three aims: 1) to measure fasting appetite hormones with a focus on plasma oxytocin concentrations; 2) determine whether healthy vs. hyperpalatable visual food cues differentially altered plasma oxytocin; and 3) assess whether appetite hormone responses to healthy vs. hyperpalatable food images depended on weight or food addiction status. Eighteen healthy women of varying weight status, with/without self-reported food addiction were recruited. Study participants completed a set of standardised questionnaires, including Yale Food Addiction Scale, and attended a one-off experimental session. Blood was collected before and after viewing two sets of food images (healthy and hyperpalatable foods). Participants were randomly allocated in a crossover design to view either healthy images or hyperpalatable foods first. A positive correlation between BMI and plasma oxytocin was found (r = 0.32, p = 0.021) at baseline. Oxytocin levels were higher, and cholecystokinin levels lower, in food addicted (n = 6) vs. non-food addicted females (p = 0.015 and p<0.001, respectively). There were no significant changes (p>0.05) in plasma oxytocin levels in response to either healthy or hyperpalatable food images. Given that endogenous oxytocin administration tends to suppress eating behaviour; these data indicate that oxytocin receptor desensitization or oxytocin resistance may be important factors in the pathogenesis of obesity and food addiction. However, further studies in larger samples are needed to determine if peripheral oxytocin is responsive to visual food cues.
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http://dx.doi.org/10.1016/j.physbeh.2019.112684DOI Listing
December 2019

Food matrix and co-presence of turmeric compounds influence bioavailability of curcumin in healthy humans.

Food Funct 2019 Aug 26;10(8):4584-4592. Epub 2019 Jul 26.

Riddet Institute, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand.

The natural food-derived compound curcumin (from turmeric root) is known for its anti-inflammatory and anti-oxidant effects. However, due to its poor solubility when consumed in isolation, it is poorly bioavailable. In this crossover study we compared the bioavailability of curcumin from a meal containing either curcumin powder, turmeric powder or grated fresh turmeric root, all containing 400 mg of curcumin, along with mashed potatoes and cream. Healthy male participants consumed the meals following overnight fasting, and postprandial blood samples were taken to measure plasma curcuminoids (curcumin, dimethylcurcumin (DMC) and bisdimethylcurcumin (BDMC)). All plasma curcumin values refer to total curcumin (sum of free and conjugated curcumin). The meals were also analysed using confocal laser scanning microscopy to determine the location of curcuminoids. Both of the turmeric meals produced significantly higher amounts (p < 0.05) of plasma curcuminoids at 1-3 hours after the meal was consumed, as compared to the curcumin powder. Plasma curcumin C was 4.9 ng ml 95% CI (confidence interval) [2.2, 7.5] for the fresh turmeric meal, 8.4 ng ml 95% CI [4.4, 12.48] for the turmeric powder meal and 0.19 ng ml 95% [-0.08, 0.47] for the curcumin powder meal. Plasma DMC and BDMC were significantly higher (p < 0.05) following the turmeric powder meal, compared with the fresh turmeric meal and the curcumin powder meal. Microscopy images showed that the curcuminoid particles were mostly confined within curcuminoid cells in the fresh turmeric meal. They were unconfined but in clusters in the turmeric powder meal, while the curcuminoid particles appeared smaller in the curcumin powder meal. Conclusion: curcumin bioavailability is enhanced when consumed as fresh or powdered turmeric, which could be due to the co-presence of other turmeric compounds and/or a turmeric matrix effect.
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http://dx.doi.org/10.1039/c9fo01063gDOI Listing
August 2019

Modulation of Circulating Trimethylamine N-Oxide Concentrations by Dietary Supplements and Pharmacological Agents: A Systematic Review.

Adv Nutr 2019 09;10(5):876-887

Nutraceuticals Research Program, School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia.

Discovery of the association of plasma/serum trimethylamine N-oxide (TMAO) concentrations with atherosclerosis has sparked immense interest in exploring TMAO as a predictor of cardiovascular disease risk. A spectrum of antibiotics and other therapeutic strategies have been employed to test their potential to modulate TMAO concentrations, assuming the gut microbiome to be the key source of TMAO. The aim of this systematic review was to determine whether dietary supplements or pharmacological agents affect TMAO concentrations in adults. Six databases were searched (Medline, EMBASE, CINAHL, Scopus, ProQuest, and PubMed) for randomized and nonrandomized controlled trials. Searches were limited to the English language and to studies in adults. Thirteen eligible trials were identified, including 6 studies on dietary supplements and 7 on pharmacological agents. Whereas intervention studies involving dietary supplements were mostly randomized controlled trials, those involving pharmacological agents appeared opportunistic and varied greatly in study design and duration. Different interventional products were tested, and the studies lacked the consistency to reliably synthesize any evidence for the modifiability of TMAO concentrations by dietary supplements or pharmacological agents. Choline and l-carnitine are conditionally essential nutrients, and carefully designed placebo-controlled randomized trials specifically aimed at reducing the synthesis of microflora-dependent TMAO production from choline-containing precursors by pro- and/or prebiotics, antibiotics, or other pharmaceutical agents may be the way forward for future research.
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http://dx.doi.org/10.1093/advances/nmz012DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6743816PMC
September 2019

Association between plasma phospholipid omega-3 polyunsaturated fatty acids and type 2 diabetes is sex dependent: The Hunter Community Study.

Clin Nutr 2020 04 13;39(4):1059-1066. Epub 2019 Apr 13.

Nutraceuticals Research Program, School of Biomedical Sciences and Pharmacy, University of Newcastle, NSW, Australia. Electronic address:

Background & Aims: Chronic inflammation drives the development of insulin resistance and type 2 diabetes. Long-chain omega-3 polyunsaturated fatty acids (LCn-3PUFA) eicosapentaenoic acid (EPA, c20:5n-3) and docosahexaenoic acid (DHA, c22:6n-3) may protect against type 2 diabetes development. The aim of this current study is to determine whether LCn-3PUFA status is associated with type 2 diabetes in the Hunter Community Study.

Methods: Men and women aged 55-85 years were randomly selected from the electoral roll and invited to participate. Participants were included in the current study if they had plasma phospholipid fatty acid composition data available and diabetes status could be determined. LCn-3PUFA status was determined by fatty acid composition of plasma phospholipids (EPA + DHA, %,w/w). Diabetes was determined according to World Health Organisation criteria. Insulin was measured in n = 251 participants and HOMA-IR calculated.

Results: In total, n = 2092 (diabetes: n = 249) participants were included. After adjusting for confounders of diabetes, LCn-3PUFA status was inversely associated with diabetes in overweight/obese females (OR [95%CI]: 0.90 [0.80, 1.00], p = 0.045) but not males (p-interaction = 0.041). Overweight/obese females with diabetes had significantly lower levels of DHA than those without diabetes (mean difference [95%CI]: -0.53 [-0.87, -0.20], p = 0.002), with no difference in EPA. LCn-3PUFA was inversely associated with HOMA-IR (r = -0.175, p = 0.005).

Conclusions: This study provides further evidence of a sex-dependent association between LCn-3PUFA and type 2 diabetes. Causal pathways between LCn-3PUFA and type 2 diabetes merits delineation.
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http://dx.doi.org/10.1016/j.clnu.2019.04.007DOI Listing
April 2020

Bread enriched with phytosterols with or without curcumin modulates lipoprotein profiles in hypercholesterolaemic individuals. A randomised controlled trial.

Food Funct 2019 May;10(5):2515-2527

Nutraceuticals Research Program, School of Biomedical Sciences & Pharmacy, 305C Medical Science Building, University of Newcastle, Callaghan, NSW 2308, Australia.

We previously demonstrated that the combination of phytosterols (PS) and curcumin administered as dietary supplements significantly lowers LDL-cholesterol (LDL-C) more than either treatment alone. The aim of this study was to investigate the effects of this combination in a novel food (bread) on plasma lipid profiles in hypercholesterolaemic individuals. In a double-blinded, placebo-controlled, 2 × 2 factorial trial, participants were randomised to receive bread fortified with placebo (PL), 2.3 g PS (PS), 228 mg curcumin (CC) or a combination of 2.3 g PS and 228 mg CC (PS-CC) daily for four weeks. Primary outcomes were fasting plasma lipids [total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglycerides (TG)] and secondary outcomes were plasma LDL-particle (LDL-P) profile: LDL-P number and LDL-P size. Cardiovascular disease (CVD) risk (Framingham Risk Algorithm) was also explored. There was no significant difference between PL and CC or PS and PS-CC on blood lipids or CVD risk; therefore, groups were pooled for final analysis: the PL and CC group (PL-C, n = 36) and the PS and PS-CC group (PS-C, n = 39). PS-C significantly lowered TC (-0.52 mmol L-1, p < 0.0001), LDL-C (-0.49 mmol L-1, p < 0.0001) and CVD risk (-1.1 absolute %, p = 0.0005) compared to the PL-C group. Reductions from baseline in the PS-C group compared to that in the PL-C group were 7.6% and 10.6% for TC and LDL-C, respectively, and statistically significant (p < 0.0001). CVD-risk in the PS-C group reduced significantly (-12.7%) compared to that in the PL-C group (p = 0.0005). HDL-C and TG remained unchanged. The LDL-P number significantly decreased in the PS-C group by 124.33 nmol L-1 compared to that in the PL-C group (p = 0.005) and both groups showed a significant decrease in LDL-P size (p < 0.01); however, the absolute nm change in LDL-P size did not differ between groups and the percent change in LDL-P size in the PS-C group was borderline significant (-0.89%, p = 0.05) compared to that in the PL-C group. Regular consumption of PS-enriched bread with or without curcumin lowers blood cholesterol; however, curcumin alone did not influence blood lipids. Bread may be a convenient means of delivering PS with greater compliance for reducing the blood cholesterol concentration.
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http://dx.doi.org/10.1039/c8fo02512fDOI Listing
May 2019

Medium-chain fatty acids lower postprandial lipemia: A randomized crossover trial.

Clin Nutr 2020 01 16;39(1):90-96. Epub 2019 Feb 16.

Nutraceuticals Research Program, School of Biomedical Sciences & Pharmacy, University of Newcastle, 305C Medical Science Building, Callaghan, NSW 2308, Australia; Riddet Institute, Massey University, Palmerston North, New Zealand. Electronic address:

Epidemiological and interventional studies have linked saturated fatty acids (SFA) with elevated levels of low-density lipoprotein cholesterol (LDL-C) and increased CVD risk. However, the effects of the SFA chain length on postprandial lipemia in humans are not well elucidated. The aim of this study was to investigate the impact of short, medium and long-chain SFA on postprandial blood lipids in healthy volunteers. Sixteen healthy volunteers consumed test biscuits containing 40 g of either butter (BB), coconut oil (CB) or lard (LB) in a single-blinded, randomized crossover design. Blood samples were collected fasting and 2, 3, 4, and 6 hours postprandially and assessed for blood lipids (total cholesterol, TC; high-density lipoprotein cholesterol, HDL-C; LDL-C and triglyceride, TG). The postprandial TG response following CB was 59.8% lower than following BB (p < 0.01) and 58.8% lower than LB (p < 0.01), although no difference was observed between the BB and the LB responses. The net area under the LDL-C concentration curve was significantly larger after consumption of the CB compared to the BB, despite no significant differences in postprandial net area under the TC and HDL-C concentration curves. Consumption of medium-chain SFA as CB resulted in lower postprandial TG excursions compared to short-chain SFA as BB and long-chain SFA as LB, despite their identical fat and caloric content. These results suggest that SFA differ in their potential to elevate postprandial lipid levels, and that coconut oil, a rich source of medium-chain SFA may not be as hyperlipidemic as animal fats rich in long chain SFA. ANZCTR IDENTIFIER: 12617000903381. CLINICAL TRIAL REGISTRY NUMBER: The study was registered with the Australia New Zealand Trial registry as ACTRN12617000903381.
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http://dx.doi.org/10.1016/j.clnu.2019.02.008DOI Listing
January 2020

Increased α-Linolenic Acid Intake during Pregnancy is Associated with Higher Offspring Birth Weight.

Curr Dev Nutr 2019 Feb 18;3(2):nzy081. Epub 2018 Oct 18.

Boden Institute of Obesity, Nutrition, Exercise and Eating Disorders, University of Sydney, Sydney, Australia.

Background: The amount and type of fat in the maternal diet during pregnancy are important contributors to fetal growth. The importance of plant-based omega-3 fatty acid (α-linolenic acid, ALA) intake in fetal growth has not been previously examined.

Objective: We sought to determine the association of maternal ALA intake during pregnancy with birth weight and body composition of the offspring.

Methods: Mothers and their newborn infants ( = 224) were recruited from the Royal Prince Alfred Hospital, Australia. Maternal diet during pregnancy was assessed using a validated food frequency questionnaire. Plasma fatty acid composition was analyzed in a subset of mothers ( = 41). Newborn body composition was assessed using air-displacement plethysmography. All analyses were adjusted for gestational age, sex, physical activity, and total energy intake.

Results: Dietary fatty acid intakes were positively associated with plasma phospholipid fatty acids for total omega-3 fatty acids (= 0.452, = 0.003), ALA (= 0.339, = 0.03), linoleic acid (= 0.353, = 0.03), eicosapentaenoic acid (= 0.407, = 0.009), and docosahexaenoic acid (= 0.388, = 0.01). Higher maternal intake of ALA (% total fat) was associated with higher offspring birth weight [189.7-g increase per 1% higher ALA (95% CI: 14, 365 g); = .04], although individually neither newborn fat mass nor fat-free mass was significant. Birth weight increased across tertiles of maternal ALA intake (= 0.05), with birth weight being 221 g (95% CI: 12, 429 g) higher in those with the highest maternal ALA intake compared with those with the lowest intake (= 0.04). Mothers of infants born small for gestational age ( = 32) had a lower ALA intake than those born appropriate for gestational age ( = 162) or large for gestational age [( = 21); = 0.05].

Conclusions: In otherwise healthy women giving birth at a major tertiary hospital in Australia, intake of ALA during pregnancy is associated with higher offspring birth weight. This may have implications for dietary strategies aimed at optimizing fetal growth via modification of maternal diet.
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http://dx.doi.org/10.1093/cdn/nzy081DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6390041PMC
February 2019

Effect of Fish Oil Supplementation on Hepatic and Visceral Fat in Overweight Men: A Randomized Controlled Trial.

Nutrients 2019 Feb 23;11(2). Epub 2019 Feb 23.

Faculty of Health Sciences, The University of Sydney, Lidcombe, NSW 2141, Australia.

Being overweight increases the risk of the development of metabolic conditions such as non-alcoholic fatty liver disease (NAFLD), which is itself an independent predictor of cardiovascular disease. Omega-3 polyunsaturated fatty acid (PUFA) supplementation is recommended for prevention of chronic disease, and is thought to reduce raised liver fat, yet there have been few randomized controlled trials with accurate measurement of liver fat. We assessed the effect of 12 weeks of supplementation with omega-3 PUFA from fish oil versus placebo on quantified liver fat, liver tests, and body composition including visceral adipose tissue (VAT) in a double-blind randomized controlled trial. Fifty apparently healthy overweight men (BMI 25.0⁻29.9 kg/m²; waist > 94 cm) were randomly allocated to consume fish oil (total daily dose: 1728 mg marine triglycerides, of which 588 mg EPA and 412 mg DHA, combined with 200 mg antioxidant, coenzyme Q10) or placebo (olive oil capsules) daily for 12 weeks. Liver fat was assessed using proton magnetic resonance spectroscopy. All outcomes were assessed at baseline and following 6 and 12 weeks of supplementation. Baseline liver fat was 4.6 ± 0.5% (range: 0.6 to 18.2%); 16 (32%) participants met the criteria for NAFLD (>5.5% liver fat). Repeated measures ANOVA revealed no significant time or group × time effect for fish oil versus placebo for liver fat, liver enzymes, anthropometry, or body composition including VAT ( > 0.05 for all), with similar finding for sub-analysis of participants with NAFLD. Omega-3 PUFA did not appear to be an effective agent for reducing liver fat in overweight men. The factors determining the health benefits of omega-3 PUFA supplementation on an individual level need to be clarified.
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http://dx.doi.org/10.3390/nu11020475DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6413081PMC
February 2019

High molecular weight oat β-glucan enhances lipid-lowering effects of phytosterols. A randomised controlled trial.

Clin Nutr 2020 01 10;39(1):80-89. Epub 2019 Feb 10.

Nutraceuticals Research Program, School of Biomedical Sciences & Pharmacy, 305C Medical Science Building, University of Newcastle, Callaghan, NSW, 2308, Australia. Electronic address:

Background & Aims: Oat β-glucan (OBG) and phytosterols (PS) are known to lower blood cholesterol levels via different mechanisms. Combination of high molecular weight (MW) OBG and PS in a single functional food could have complementary and/or synergistic effects for optimising heart health. The aim of this study was to investigate the effects of dietary supplementation with high-MW OBG with or without PS on plasma lipids in hypercholesterolaemic individuals.

Methods: In a double-blinded, placebo-controlled, 2 × 2 factorial trial, participants were randomised to receive biscuits fortified with either no PS or OBG (PL, n = 18) or 2 g PS (PS, n = 18), 3 g OBG (OBG, n = 18), or combination of 2 g PS and 3 g OBG (PS-OBG, n = 18) per day for 6 weeks. Primary outcome was fasting plasma total cholesterol (TC) and secondary outcomes were LDL-cholesterol, LDL-C; HDL-cholesterol, HDL-C; triglycerides, TG and TC to HDL-cholesterol (TC:HDL) ratio.

Results: TC and LDL-C were significantly lowered following PS (-4.6% and -7.6% respectively; p < 0.05), OBG (-5.7% and -8.6%; p < 0.01) and PS-OBG (-11.5% and -13.9%; p < 0.0001) administration. The reduction in TC in the PS-OBG group was significantly greater compared to PL (p < 0.001) and PS (p < 0.05). PS-OBG group had a significantly greater reduction in LDL-C compared to PL (p < 0.01) but not in comparison to PS or OBG groups. TC:HDL ratio was significantly reduced following PS-OBG (-8.9%; p < 0.01) only, and there was no significant difference found between groups. Plasma TG reduced by 8.4% following PS-OBG, however, this was statistically non-significant. Plasma HDL-C remained unchanged across all groups.

Conclusions: Dietary supplementation with high-MW OBG and PS in a single functional food enhances their lipid-lowering potential. Blood cholesterol lowering by PS and OBG is additive. Delivery of these two bioactive nutrients in a single food allows optimisation of their lipid-lowering effects and may provide added heart health benefits with enhanced compliance. The trial was registered with the Australian New Zealand Clinical Trials Registry at http://www.anzctr.org.au/(ACTRN12618001455257).
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http://dx.doi.org/10.1016/j.clnu.2019.02.007DOI Listing
January 2020

Curcumin and/or omega-3 polyunsaturated fatty acids supplementation reduces insulin resistance and blood lipids in individuals with high risk of type 2 diabetes: a randomised controlled trial.

Lipids Health Dis 2019 Jan 26;18(1):31. Epub 2019 Jan 26.

Nutraceuticals Research Program, School of Biomedical Sciences & Pharmacy, University of Newcastle, 305C Medical Science Building, Callaghan, NSW, 2308, Australia.

Background: Lowering insulin resistance and dyslipidaemia may not only enhance glycaemic control but also preserve the β-cell function, reducing the overall risk of developing type 2 diabetes (T2D). The current study was aimed to evaluate the effects of curcumin and/or long-chain omega-3 polyunsaturated fatty acids (LCn-3PUFA) supplementation on glycaemic control and blood lipid levels in individuals at high risk of developing T2D.

Methods: This was a 2 × 2 factorial, randomised, double-blinded, placebo-controlled study. Participants were allocated to either double placebo (PL) or curcumin plus placebo matching for LCn-3PUFA (CC), or LCn-3PUFA plus placebo matching for curcumin (FO), or curcumin plus LCn-3PUFA (CC-FO) for twelve weeks. Primary outcome of the trial was glycaemic indices (HbA1C, fasting glucose and insulin). Insulin resistance and sensitivity is measured using homeostatic model assessment model.

Results: A total of sixty-four participants (PL, n = 16; CC, n = 15; FO, n = 17, CC-FO, n = 16) were included in the final analysis. Post-intervention, HbA1c and fasting glucose remained unchanged across all the groups. Insulin sensitivity was significantly improved in the CC supplemented group (32.7 ± 10.3%) compared to PL (P = 0.009). FO and CC-FO tended to improve insulin sensitivity by 14.6 ± 8.5% and 8.8 ± 7.7% respectively, but the difference did not reach significance. Triglyceride levels were further increased in the PL (26.9 ± 7.4%), however, CC and CC-FO supplementation reduced the triglycerides, FO resulted in the greatest reduction in triglycerides (- 16.4 ± 4.5%, P < 0.001).

Conclusion: Reduction in insulin resistance and triglycerides by curcumin and LCn-3PUFA appears to be attractive strategies for lowering the risk of developing T2D. However, this study failed to demonstrate complimentary benefits of curcumin and LCn-3PUFA on glycaemic control.

Trail Registration: ACTRN12615000559516 .
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http://dx.doi.org/10.1186/s12944-019-0967-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6347796PMC
January 2019

Effect of the food form and structure on lipid digestion and postprandial lipaemic response.

Food Funct 2019 Jan;10(1):112-124

Riddet Institute, Massey University, Palmerston North, New Zealand.

As the food matrix is a determinant of the rate of fat digestion and absorption, it is important for the modulation of postprandial triglyceridaemia. High postprandial triglyceride levels are associated with an increase in inflammation, oxidative stress, an imbalance in the lipoprotein profile and an increase in the risk of developing chronic diseases. This study was designed to assess the in vitro digestion patterns and the postprandial lipaemic responses to test foods with the same nutrient composition but differing in the form and structure. A liquid, a semi-solid and a solid test food with the same nutrient and energy composition were designed. The digestion profiles of the three foods were assessed using a dynamic in vitro model. The foods were also consumed by healthy young adults who donated blood samples after an overnight fast and again 0.5, 1, 2, 3, 4 and 6 h after consuming each of the test foods and who were also assessed for appetite sensations. The solid food showed phase separation during gastric digestion and a lower release of fatty acids during intestinal digestion than the liquid and semi-solid foods. During the postprandial feeding experiments, the solid food caused a lower increase in serum triglycerides than the liquid food and produced higher fullness and satisfaction. In conclusion, the food form and structure modulated fat release, postprandial triglyceridaemia and appetite sensations independent of the nutrient and energy content. Thus, manipulation of the food structure and form may be used in designing strategies for improving metabolic markers and satiety.
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http://dx.doi.org/10.1039/c8fo01698dDOI Listing
January 2019

The relationship between oxytocin, dietary intake and feeding: A systematic review and meta-analysis of studies in mice and rats.

Front Neuroendocrinol 2019 01 10;52:65-78. Epub 2018 Oct 10.

Nutrition and Dietetics, School of Health Sciences, Faculty of Health and Medicine, University of Newcastle, Callaghan, NSW 2308, Australia; Priority Research Centre for Physical Activity and Nutrition, University of Newcastle, Callaghan, NSW 2308, Australia. Electronic address:

The neuropeptide oxytocin has been associated with food intake and feeding behaviour. This systematic review aimed to investigate the impact of oxytocin on dietary intake and feeding behaviour in rodent studies. Six electronic databases were searched to identify published studies to April 2018. Preclinical studies in mice and rats were included if they reported: (1) a dietary measure (i.e. food or nutrient and/or behaviour (2) an oxytocin measure, and (3) relationship between the two measures. A total of 75 articles (n = 246 experiments) were included, and study quality appraised. The majority of studies were carried out in males (87%). The top three oxytocin outcomes assessed were: exogenous oxytocin administration (n = 126), oxytocin-receptor antagonist administration (n = 46) and oxytocin gene deletion (n = 29). Meta-analysis of exogenous studies in mice (3 studies, n = 43 comparisons) and rats (n = 8 studies, n = 82 comparisons) showed an overall decrease in food intake with maximum effect shown at 2 h post-administration.
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http://dx.doi.org/10.1016/j.yfrne.2018.09.002DOI Listing
January 2019

Differential effects of medium- and long-chain saturated fatty acids on blood lipid profile: a systematic review and meta-analysis.

Am J Clin Nutr 2018 10;108(4):675-687

Nutraceuticals Research Program, School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia.

Background: Medium-chain saturated fatty acids (MCFAs) may affect circulating lipids and lipoproteins differently than long-chain saturated fatty acids (LCSFAs), but the results from human intervention trials have been equivocal.

Objective: The aim of this study was to determine whether MCFAs and LCSFAs have differential impacts on blood lipids and lipoproteins.

Design: Five databases were searched (EMBASE, MEDLINE, CINAHL, Cochrane, and Scopus) until April 2018, and published clinical trials investigating the differential effects of dietary MCFAs and LCSFAs on blood lipids were included. Searches were limited to the English language and to studies with adults aged >18 y. Where possible, studies were pooled for meta-analysis using RevMan 5.2. The principle summary measure was the mean difference between groups calculated using the random-effects model.

Results: Eleven eligible crossover and 1 parallel trial were identified with a total of 299 participants [weighted mean ± SD age: 38 ± 3 y; weighted mean ± SD body mass index (kg/m2): 24 ± 2]. All studies were pooled for the meta-analysis. Diets enriched with MCFAs led to significantly higher high-density lipoprotein (HDL) cholesterol concentrations than diets enriched with LCSFAs (0.11 mmol/L; 95% CI: 0.07, 0.15 mmol/L) with no effect on triglyceride, low-density lipoprotein (LDL) cholesterol, and total cholesterol concentrations. Consumption of diets rich in MCFAs significantly increased apolipoprotein A-I (apoA-I) concentrations compared with diets rich in LCSFAs (0.08 g/L; 95% CI: 0.02, 0.14 g/L). There was no evidence of statistical heterogeneity for HDL cholesterol, apoA-I, and triglyceride concentrations; however, significant heterogeneity was observed for the total cholesterol (I2 = 49%) and LDL cholesterol analysis (I2 = 58%).

Conclusion: The findings of this research demonstrate a differential effect of MCFAs and LCSFAs on HDL cholesterol concentrations. Further investigations are warranted to elucidate the mechanism by which the lipid profile is altered. This trial was registered at www.crd.york.ac.uk/PROSPERO as CRD42017078277.
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http://dx.doi.org/10.1093/ajcn/nqy167DOI Listing
October 2018

Curcumin alleviates postprandial glycaemic response in healthy subjects: A cross-over, randomized controlled study.

Sci Rep 2018 09 12;8(1):13679. Epub 2018 Sep 12.

Nutraceuticals Research Program, School of Biomedical Sciences & Pharmacy, University of Newcastle, Callaghan, NSW, Australia.

In the current study, we aimed to evaluate the effects of a single dose of curcumin and/or fish oil on postprandial glycaemic parameters in healthy individuals. This was a randomised, placebo-controlled and crossover study. Sixteen (n = 16) volunteers were randomised to receive placebo, curcumin (180 mg) tablets, fish oil (1.2 g long chain omega-3 polyunsaturated fatty acids) capsules and curcumin + fish oil prior to a standard meal on 4 test days separated by a week. Blood glucose, serum insulin and triglycerides were measured at intervals between 0-120 min. Difference between the treatments was measured using two-way repeated measures analysis of variance and pair-wise comparisons using Wilcoxon signed-rank or paired t-test as appropriate. Postprandial glucose concentrations were significantly lower in the curcumin (60.6%, P = 0.0007) and curcumin + fishoil group (51%, P = 0.002) groups at 60 min from baseline. Compared with placebo, area under the curve (AUC) for change in blood glucose concentration was reduced by curcumin (36%, P = 0.003) and curcumin + fishoil (30%, 0.004), but not fish oil alone (p = 0.105). Both curcumin (P = 0.01) and curcumin + fishoil (P = 0.03) treatments significantly lowered postprandial insulin (AUC) by 26% in comparison with placebo. Curcumin, but not fish oil, reduces postprandial glycaemic response and insulin demand for glucose control.
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http://dx.doi.org/10.1038/s41598-018-32032-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6135827PMC
September 2018

Science behind the cardio-metabolic benefits of omega-3 polyunsaturated fatty acids: biochemical effects vs. clinical outcomes.

Food Funct 2018 Jul;9(7):3576-3596

Nutraceuticals Research Program, School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW, Australia.

Lower incidence of cardiovascular disease (CVD) in the Greenland Inuit, Northern Canada and Japan has been attributed to their consumption of seafood rich in long chain omega-3 polyunsaturated fatty acids (LCn-3PUFA). While a large majority of pre-clinical and intervention trials have demonstrated heart health benefits of LCn-3PUFA, some studies have shown no effects or even negative effects. LCn-3PUFA have been shown to favourably modulate blood lipid levels, particularly a reduction in circulating levels of triglycerides. High density lipoprotein-cholesterol (HDL-C) levels are elevated following dietary supplementation with LCn-3PUFA. Although LCn-3PUFA have been shown to increase low-density lipoprotein-cholesterol (LDL-C) levels, the increase is primarily in the large-buoyant particles that are less atherogenic than small-dense LDL particles. The anti-inflammatory effects of LCn-3PUFA have been clearly outlined with inhibition of NFkB mediated cytokine production being the main mechanism. In addition, reduction in adhesion molecules (intercellular adhesion molecule, ICAM and vascular cell adhesion molecule 1, VCAM-1) and leukotriene production have also been demonstrated following LCn-3PUFA supplementation. Anti-aggregatory effects of LCn-3PUFA have been a subject of controversy, however, recent studies showing sex-specific effects on platelet aggregation have helped resolve the effects on hyperactive platelets. Improvements in endothelium function, blood flow and blood pressure after LCn-3PUFA supplementation add to the mechanistic explanation on their cardio-protective effects. Modulation of adipose tissue secretions including pro-inflammatory mediators and adipokines by LCn-3PUFA has re-ignited interest in their cardiovascular health benefits. The aim of this narrative review is to filter out the reasons for possible disparity between cohort, mechanistic, pre-clinical and clinical studies. The focus of the article is to provide possible explanation for the observed controversies surrounding heart health benefits of LCn-3PUFA.
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http://dx.doi.org/10.1039/c8fo00348cDOI Listing
July 2018

Relationship between dietary intake and behaviors with oxytocin: a systematic review of studies in adults.

Nutr Rev 2018 05;76(5):303-331

Nutrition and Dietetics School of Health Sciences, Faculty of Health and Medicine, University of Newcastle, Callaghan, New South Wales, Australia.

Context: Oxytocin plays an important hormonal role in the regulation of feeding and energy intake.

Objective: The aims of this review were to 1) determine the effects of dietary intake/behaviors on endogenous oxytocin and 2) examine the effect of exogenous oxytocin on dietary intake/behaviors.

Data Sources: Published studies up to December 2016 were identified through searches of 5 electronic databases.

Data Extraction: Eligible studies included those in adults that included a measure related to an individual's diet and a measure of oxytocin and the relationship between the 2 outcomes.

Results: Twenty-six studies (n = 912 participants; 77% female) were included. The most common dietary outcomes assessed were alcohol, caffeine, calcium, sodium, fat, and calorie intake. It was found that endogenous oxytocin (n = 13) in nonclinical samples did not change significantly (P > 0.05) through altered diet or behaviors (neutral effect); in contrast, significant (P < 0.05) differences (increases and decreases) were identified in clinical samples. Exogenous oxytocin studies (n = 13) found reduced indices of food intake (positive effect) in clinical and nonclinical samples.

Conclusions: Overall, few studies included comprehensive investigation of dietary intakes through the use of validated assessment tools. Dietary intake and behaviors appear to have some influence on oxytocin, with more pronounced effects found with exogenously administered oxytocin.
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http://dx.doi.org/10.1093/nutrit/nux078DOI Listing
May 2018

Regulation of Carbon Partitioning in the Seed of the Model Legume and : A Comparative Approach.

Front Plant Sci 2017 12;8:2070. Epub 2017 Dec 12.

School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW, Australia.

The proportion of starch, protein and oil in legume seeds is species dependent. The model legume, , has predominantly oil and protein stores. To investigate the regulation of seed oil production we compared with , which has less oil and protein. The types of protein and fatty acids are similar between the two species. Electron microscopy indicated that the size and distribution of the oil bodies in , is consistent with reduced oil production. has more extruded endosperm mucilage compared to The cotyledons have a greater cell wall content, visualized as thicker cell walls. The reduced oil content in is associated with increased expression of the () transcription factor, linked to an inverse relationship between mucilage and oil content in Arabidopsis. The expression of the pectin biosynthesis () genes, is also increased in . These increases in extruded mucilage and cell wall storage components in are accompanied by reduced expression of transcriptional regulators of oil biosynthesis, (), (), and (), in . The reduced oil in , is consistent with increased synthesis of cell wall polysaccharides and decreased expression of master transcription factors regulating oil biosynthesis and embryo maturation. Comparative investigations between these two species is a useful system to investigate the regulation of oil content and carbon partitioning in legumes.
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http://dx.doi.org/10.3389/fpls.2017.02070DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5733034PMC
December 2017

LipSpin: A New Bioinformatics Tool for Quantitative H NMR Lipid Profiling.

Anal Chem 2018 02 17;90(3):2031-2040. Epub 2018 Jan 17.

Department of Electronic Engineering, Universitat Rovira i Virgili , Metabolomics Platform, URV, Tarragona, 43007, Spain.

The structural similarity among lipid species and the low sensitivity and spectral resolution of nuclear magnetic resonance (NMR) have traditionally hampered the routine use of H NMR lipid profiling of complex biological samples in metabolomics, which remains mostly manual and lacks freely available bioinformatics tools. However, H NMR lipid profiling provides fast quantitative screening of major lipid classes (fatty acids, glycerolipids, phospholipids, and sterols) and some individual species and has been used in several clinical and nutritional studies, leading to improved risk prediction models. In this Article, we present LipSpin, a free and open-source bioinformatics tool for quantitative H NMR lipid profiling. LipSpin implements a constrained line shape fitting algorithm based on voigt profiles and spectral templates from spectra of lipid standards, which automates the analysis of severely overlapped spectral regions and lipid signals with complex coupling patterns. LipSpin provides the most detailed quantification of fatty acid families and choline phospholipids in serum lipid samples by H NMR to date. Moreover, analytical and clinical results using LipSpin quantifications conform with other techniques commonly used for lipid analysis.
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http://dx.doi.org/10.1021/acs.analchem.7b04148DOI Listing
February 2018

Curcumin potentiates cholesterol-lowering effects of phytosterols in hypercholesterolaemic individuals. A randomised controlled trial.

Metabolism 2018 05 29;82:22-35. Epub 2017 Dec 29.

Nutraceuticals Research Program, School of Biomedical Sciences & Pharmacy, 305C Medical Science Building, University of Newcastle, Callaghan, NSW 2308, Australia. Electronic address:

Background: Dietary phytosterols (PS) are well-known hypocholesterolaemic agents. Curcumin elicits hypolipidaemic and anti-inflammatory effects in preclinical studies, however, consistent findings in humans are lacking.

Objective: Concurrent PS and curcumin supplementation may exhibit enhanced hypocholesterolaemic and anti-inflammatory effects to optimise cardio-protection. The objective of this trial was to investigate the effects of dietary intervention with PS with or without curcumin on blood lipids (primary outcome) in hypercholesterolaemic individuals.

Methods: A double-blinded, randomised, placebo-controlled, 2 × 2 factorial trial was conducted in hypercholesterolaemic individuals. Participants received either placebo (PL, no phytosterols or curcumin), phytosterols (PS, 2 g/d), curcumin (CC, 200 mg/d) or a combination of PS and curcumin (PS-CC, 2 g/d-200 mg/d respectively) for four weeks. Primary outcomes included fasting total cholesterol (TC), LDL-cholesterol, HDL-cholesterol, triglycerides (TG), TC-to-HDL-C ratio (TC:HDL-C). Secondary outcomes included anthropometrics and fasting blood glucose concentrations.

Results: Seventy participants with a mean (±SEM) fasting TC concentration of 6.57 ± 0.13 mmol/L completed the study (PL, n = 18; PS, n = 17; CC, n = 18; PS-CC, n = 17). PS and PS-CC supplementation significantly lowered TC, LDL-cholesterol and TC:HDL-C post-intervention (p < 0.05). Reductions from baseline in the PS group were 4.8% and 8.1% for TC and LDL-cholesterol respectively (p < 0.05). CC exhibited non-significant reduction (2.3% and 2.6%) in TC and LDL-C respectively, however, the PS-CC resulted in a greater reduction in TC (11.0%) and LDL-cholesterol (14.4%) than either of the treatments alone (p < 0.0001). The reduction in the PS-CC treatment was significantly greater compared to those for CC (p < 0.05) or PL (p < 0.01) alone. Plasma HDL-cholesterol and TG concentrations remained unchanged across all groups. No adverse side effects were reported.

Conclusions: The addition of curcumin to phytosterol therapy provides a complementary cholesterol-lowering effect that is larger than phytosterol therapy alone. Implications of these findings include the development of a single functional food containing both the active ingredients for enhanced lipid-lowering and compliance in hypercholesterolaemic individuals. ANZCTR identifier: 1261500095650.
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http://dx.doi.org/10.1016/j.metabol.2017.12.009DOI Listing
May 2018

Relationship between Obesity and Cognitive Function in Young Women: The Food, Mood and Mind Study.

J Obes 2017 8;2017:5923862. Epub 2017 Oct 8.

Discipline of Exercise and Sport Science, Faculty of Health Sciences, University of Sydney, Lidcombe, NSW, Australia.

Limited research addresses links between obesity and cognitive function in young adults. . To investigate the relationship between obesity and cognitive function in young women. . This cross-sectional study recruited healthy, young (18-35 y) women of normal (NW: BMI = 18.5-24.9 kg·m) or obese (OB: BMI ≥ 30.0 kg·m) weight. Participants completed a validated, computer-based cognitive testing battery evaluating impulsivity, attention, information processing, memory, and executive function. Questionnaires on depression and physical activity and a fasting blood sample for C-reactive protein and the Omega-3 Index were also collected. Cognition data are presented as -scores (mean ± SD), and group comparisons were assessed via ANOVA. Potential confounding from questionnaire and blood variables were evaluated using ANCOVA. . 299 women (NW:  = 157; OB:  = 142) aged 25.8 ± 5.1 y were enrolled. Cognition scores were within normal range (±1 -score), but OB had lower attention (NW: 0.31 ± 1.38; OB: -0.25 ± 1.39; ES: 0.41, CI: 0.17-0.64; < 0.001) and higher impulsivity (NW: 0.36 ± 1.14; OB: -0.07 ± 1.07; ES: 0.39, CI: 0.15-0.62; =0.033). Confounder adjustment had minimal impact on results. . The OB group had normal but significantly lower performance on attention and were more impulsive compared to NW participants. This may indicate early cognitive decline, but longitudinal research confirming these findings is warranted.
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http://dx.doi.org/10.1155/2017/5923862DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5651104PMC
January 2019

Fish oil supplementation in chronic obstructive pulmonary disease: feasibility of conducting a randomised controlled trial.

Pilot Feasibility Stud 2017 25;3:66. Epub 2017 Nov 25.

Alliance for Research in Exercise, Nutrition and Activity, Sansom Institute for Health Research, School of Health Sciences, University of South Australia, Adelaide, South Australia 5000 Australia.

Background: Long-chain omega-3 polyunsaturated fatty acids (LCn-3PUFAs) may act as an effective adjunct therapy for chronic obstructive pulmonary disease (COPD), a condition characterised by persistent airflow limitation and inflammation. However, the nature of this illness presents challenges for evaluating potential benefits. The aim of this study was to determine the feasibility of undertaking a randomised controlled trial of LCn-3PUFA supplementation in adults with COPD.

Methods: A 16-week parallel, double-blind, randomised, placebo-controlled dietary supplementation trial was conducted. Participants diagnosed with COPD were randomly allocated to take six 1-g capsules of fish oil (3.6 g LCn-3PUFA) or corn oil (placebo) daily for 16 weeks. Key outcomes used to determine the feasibility of the trial included recruitment rate, participant retention rate and supplement adherence (blood biomarker and returned capsule count). An estimate of the effect size for clinical outcomes such as pulmonary function and functional exercise capacity was calculated.

Results: None of the key feasibility criteria were met. The enrolment target was 40 participants in 52 weeks; however, only 13 were finally enrolled, with just seven in the first 52 weeks. Eight participants completed the study (retention rate 62%). Targets for compliance were not achieved; red blood cell LCn-3PUFA content (expressed as percentage of total fatty acids) did not increase by more than 2% in the fish oil group; capsule counts were unreliable. As the target sample size was not achieved and only a small number of participants completed the study, it was not possible to use the variance in clinical outcomes to estimate a sample size for a future study.

Conclusions: This study highlights major difficulties, especially with recruitment, in conducting this LCn-3PUFA supplementation trial in people with COPD, rendering the protocol unfeasible by predetermined criteria. A modified approach is needed to investigate potential health benefits of fish oil in people with COPD. A multicentre study with changes to inclusion and exclusion criteria is recommended.

Trial Registration: Australia and New Zealand Clinical Trials Register (ANZCTR), ACTRN12612000158864.
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http://dx.doi.org/10.1186/s40814-017-0211-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5702222PMC
November 2017