Publications by authors named "Janene B Biggs"

15 Publications

  • Page 1 of 1

Lower insulin sensitivity remains a feature of children born very preterm.

Pediatr Diabetes 2021 Mar 6;22(2):161-167. Epub 2020 Nov 6.

Liggins Institute, University of Auckland, Auckland, New Zealand.

Background: The first report of children born very preterm (<32 weeks of gestation) having insulin resistance was made 16 years ago. However, neonatal care has improved since. Thus, we aimed to assess whether children born very preterm still have lower insulin sensitivity than term controls.

Methods: Participants were prepubertal children aged 5 to 11 years born very preterm (<32 weeks of gestation; n = 51; 61% boys) or at term (37-41 weeks; n = 50; 62% boys). Frequently sampled intravenous glucose tolerance tests were performed, and insulin sensitivity was calculated using Bergman's minimal model. Additional clinical assessments included anthropometry, body composition using whole-body dual-energy X-ray absorptiometry scans, clinic blood pressure, and 24-hour ambulatory blood pressure monitoring.

Results: Children born very preterm were 0.69 standard deviation score (SDS) lighter (P < .001), 0.53 SDS shorter (P = .003), and had body mass index 0.57 SDS lower (P = .003) than children born at term. Notably, children born very preterm had insulin sensitivity that was 25% lower than term controls (9.4 vs 12.6 × 10 minutes ·[mU/L]; P = .001). Other parameters of glucose metabolism, including fasting insulin levels, were similar in the two groups. The awake systolic blood pressure (from 24-hour monitoring) tended to be 3.1 mm Hg higher on average in children born very preterm (P = .054), while the clinic systolic blood pressure was 5.4 mm Hg higher (P = .002).

Conclusions: Lower insulin sensitivity remains a feature of children born very preterm, despite improvements in neonatal intensive care. As reported in our original study, our findings suggest the defect in insulin action in prepubertal children born very pretermis primarily peripheral and not hepatic.
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http://dx.doi.org/10.1111/pedi.13140DOI Listing
March 2021

Safety, feasibility and efficacy of side-alternating vibration therapy on bone and muscle health in children and adolescents with musculoskeletal disorders: A pilot trial.

J Paediatr Child Health 2020 Aug 21;56(8):1257-1262. Epub 2020 May 21.

Liggins Institute, University of Auckland, Auckland, New Zealand.

Aims: A pilot study was performed to establish the safety, feasibility and efficacy of vibration therapy (VT) on bone and muscle health in children and adolescents with a range of musculoskeletal disorders.

Methods: Seventeen participants (15.7 years ± 2.9 years), with conditions that impacted on their musculoskeletal health, completed 20 weeks of side-alternating VT for 9 min/session, 4 times/week at 20 Hz. Data were collected at baseline and after 20 weeks of intervention. Assessments included whole-body dual-energyX-ray absorptiometry, muscle function (force plate) and 6-min walk test.

Results: Compliance with the prescribed VT training protocol was relatively high overall at 78% and there were no adverse events reported. After 20 weeks intervention, functional assessments showed time taken to perform the chair test was reduced by 15% (P = 0.018), leg balance improved with standard ellipse area decreasing by 88% (P = 0.006) and distance walked in the 6-min walk test improved by 9% (P = 0.002). Participants displayed increased total body mass (1.94 kg; P = 0.018) with increased lean mass (1.20 kg; P = 0.019) but not fat mass (P = 0.19). There was no change in total body bone mineral density (P = 0.44) or bone mineral content (P = 0.07).

Conclusions: Twenty weeks of side-alternating VT was a feasible protocol that was associated with improvements in physical function and no detrimental effects on lean mass, bone mass or density in children and adolescents with musculoskeletal disorders.
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http://dx.doi.org/10.1111/jpc.14913DOI Listing
August 2020

The Effects of 20 Weeks of Side-Alternating Vibration Therapy on Physical Function, Bone and Muscle Health in Adolescents with Down Syndrome.

Phys Occup Ther Pediatr 2021 28;41(1):44-55. Epub 2020 Apr 28.

Liggins Institute, University of Auckland, Auckland, New Zealand.

Aims: To evaluate the effects of side-alternating vibration therapy on physical function and body composition in adolescents with Down syndrome.

Methods: Fourteen adolescents (8 males) with Down syndrome (mean ± SD age: 15.5 ± 2.3 years) performed vibration treatment nine minutes daily, four times per week, for 20 weeks on a Galileo vibration platform. Data were collected at baseline and after 20 weeks of intervention. Assessments included six-minute walk test, muscle function (force plate), whole-body dual-energy X-ray absorptiometry and peripheral quantitative computed tomography of the non-dominant tibia.

Results: After 20 weeks, participants increased their distance walked in the six-minute walk test ( = 0.009), 2-leg single jump efficiency ( = 0.024) and jump velocity ( = 0.046). Participants also increased their power ( = 0.034) and reduced the time taken during the chair rise test ( < 0.001). At the total body level, increases were seen in bone mineral density ( = 0.004), bone mineral content ( = 0.043), fat free mass ( = 0.013) and lean mass ( = 0.021).

Conclusion: Side-alternating vibration therapy was associated with increases in physical function and muscle mass with no effects on bone health in adolescents with Down syndrome.

Clinical Trial Registration Number: Australian New Zealand Clinical Trial Registry (ACTRN12615000092594) - registered on 4 February 2015.
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http://dx.doi.org/10.1080/01942638.2020.1758983DOI Listing
April 2020

Exercise in pregnancy: 1-year and 7-year follow-ups of mothers and offspring after a randomized controlled trial.

Sci Rep 2018 08 27;8(1):12915. Epub 2018 Aug 27.

Liggins Institute, University of Auckland, Auckland, New Zealand.

There are limited data on long-term outcomes of mothers or their offspring following exercise interventions during pregnancy. We assessed long-term effects of an exercise intervention (home-based stationary cycling) between 20-36 weeks of gestation on anthropometry and body composition in mothers and offspring after 1 and 7 years. 84 women were randomised to intervention or usual activity, with follow-up data available for 61 mother-child pairs (38 exercisers) at 1 year and 57 (33 exercisers) at 7 years. At 1 year, there were no observed differences in measured outcomes between mothers and offspring in the two groups. At the 7-year follow-up, mothers were mostly similar, except that exercisers had lower systolic blood pressure (-6.2 mmHg; p = 0.049). However, offspring of mothers who exercised during pregnancy had increased total body fat (+3.2%; p = 0.034) and greater abdominal (+4.1% android fat; p = 0.040) and gynoid (+3.5% gynoid fat; p = 0.042) adiposity compared with controls. Exercise interventions beginning during pregnancy may be beneficial to long-term maternal health. However, the initiation of exercise during pregnancy amongst sedentary mothers may be associated with adverse effects in the offspring during childhood. Larger follow-up studies are required to investigate long-term effects of exercise in pregnancy.
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http://dx.doi.org/10.1038/s41598-018-30925-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6110723PMC
August 2018

Nulliparity is associated with subtle adverse metabolic outcomes in overweight/obese mothers and their offspring.

Clin Endocrinol (Oxf) 2017 Nov 22;87(5):545-551. Epub 2017 Aug 22.

Liggins Institute, University of Auckland, Auckland, New Zealand.

Background: We aimed to evaluate metabolic outcomes in overweight/obese nulliparous and multiparous women and their offspring.

Study Design: Seventy-two overweight and obese women who participated in a randomized controlled trial of exercise in pregnancy were included in the study, comparing 18 nulliparous and 54 multiparous women and their singleton offspring. Women were assessed at 19 and 36 weeks of gestation. Fetal growth was measured using standard obstetric ultrasound techniques. Cord blood was collected at birth. Maternal and offspring body composition was assessed using DXA ~2 weeks after delivery.

Results: Nulliparous women had higher HbA1c in the third trimester of pregnancy than multiparous women (5.48% vs 5.29%; P=.002) and were more insulin-resistant based on the surrogate marker sex hormone-binding globulin (354 vs 408 nmol/L; P=.047). Nulliparous women also had higher levels of the inflammatory marker tumour necrosis factor-alpha (4.74 vs 3.62 pg/mL; P=.025). At birth, the offspring of nulliparous women were on average 340 g (P=.013) and 0.69 standard deviation scores (P=.026) lighter than those born of multiparous women. Cord blood data showed lower insulin-like growth factor-II (P=.026) and higher IGF binding protein-1 (P=.002) levels in the offspring of nulliparous women. In addition, a less favourable metabolic profile was observed in the offspring of nulliparous women, as indicated by higher triglyceride (P<.001) and interleukin-6 (P=.039) concentrations.

Conclusions: Infants born of nulliparous overweight and obese women appear to be exposed to a less favourable metabolic environment in utero, with evidence of subtle adverse metabolic outcomes at birth compared to infants of overweight/obese multiparous women.
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http://dx.doi.org/10.1111/cen.13426DOI Listing
November 2017

Non-Dipping and Cardiometabolic Profile: A Study on Normotensive Overweight Middle-Aged Men.

Heart Lung Circ 2016 Dec 17;25(12):1218-1225. Epub 2016 May 17.

Liggins Institute, University of Auckland, Auckland, New Zealand; Gravida: National Centre for Growth and Development, Auckland, New Zealand. Electronic address:

Background: We aimed to assess insulin sensitivity and other metabolic features of dippers and non-dippers among overweight middle-aged men.

Methods: We studied 73 men (45.8 ± 5.3 years) who were overweight but normotensive. Participants were separated into dippers and non-dippers based on the magnitude of the nocturnal decline of blood pressure, with dippers experiencing an overnight decline ≥10% as per standard definition. Our study included 51 dippers and 22 non-dippers. All participants underwent 24-hour ambulatory blood pressure monitoring. Insulin sensitivity was assessed by the Matsuda method from an oral glucose tolerance test; other assessments included carotid artery intima-media thickness (CIMT), body composition derived from dual-energy X-ray absorptiometry, lipid profiles, and a physical activity questionnaire.

Results: Non-dippers had lower daytime systolic (-5.0mmHg; p=0.022) and diastolic (-3.3mmHg; p=0.035) blood pressure than dippers. Conversely, during sleep, non-dippers had higher systolic (+6.5mmHg; p=0.003) and diastolic (+5.6mmHg; p=0.001) blood pressure. In continuous associations, increasing CIMT was associated with decreasing systolic (p=0.012) and diastolic (p=0.042) dipping. Thus, non-dippers had CIMT that was 9% greater than that of dippers (749 vs 820μm; p=0.036). Importantly, there was no association between non-dipping status or the magnitude of the nocturnal dip with insulin sensitivity.

Conclusions: Non-dippers had lower blood pressure in the daytime, but higher blood pressure in the night time compared to dippers. Non-dippers had increased CIMT, which suggests that normotensive men with a non-dipping ambulatory blood pressure profile may be at increased cardiovascular risk. However, it appears that the non-dipping profile is unrelated to dysfunction of glucose homeostasis in overweight normotensive men.
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http://dx.doi.org/10.1016/j.hlc.2016.04.012DOI Listing
December 2016

Effects of whole-body vibration training on physical function, bone and muscle mass in adolescents and young adults with cerebral palsy.

Sci Rep 2016 Mar 3;6:22518. Epub 2016 Mar 3.

Liggins Institute, University of Auckland, Auckland, New Zealand.

We performed a clinical trial on the effects of whole-body vibration training (WBVT) on muscle function and bone health of adolescents and young adults with cerebral palsy. Forty participants (11.3-20.8 years) with mild to moderate cerebral palsy (GMFCS II-III) underwent 20-week WBVT on a vibration plate for 9 minutes/day 4 times/week at 20 Hz (without controls). Assessments included 6-minute walk test, whole-body DXA, lower leg pQCT scans, and muscle function (force plate). Twenty weeks of WBVT were associated with increased lean mass in the total body (+770 g; p = 0.0003), trunk (+410 g; p = 0.004), and lower limbs (+240 g; p = 0.012). Bone mineral content increased in total body (+48 g; p = 0.0001), lumbar spine (+2.7 g; p = 0.0003), and lower limbs (+13 g; p < 0.0001). Similarly, bone mineral density increased in total body (+0.008 g/cm(2); p = 0.013), lumbar spine (+0.014 g/cm(2); p = 0.003), and lower limbs (+0.023 g/cm(2); p < 0.0001). Participants reduced the time taken to perform the chair test, and improved the distance walked in the 6-minute walk test by 11% and 35% for those with GMFCS II and III, respectively. WBVT was associated with increases in muscle mass and bone mass and density, and improved mobility of adolescents and young adults with cerebral palsy.
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http://dx.doi.org/10.1038/srep22518DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4776132PMC
March 2016

Supplementation with a blend of krill and salmon oil is associated with increased metabolic risk in overweight men.

Am J Clin Nutr 2015 Jul 27;102(1):49-57. Epub 2015 May 27.

Liggins Institute, University of Auckland, Auckland, New Zealand; and

Background: Krill is an increasingly popular source of marine n-3 (ω-3) PUFA that is seen as a premium product. However, to our knowledge, the effect of krill-oil supplementation on insulin sensitivity in humans has not been reported.

Objective: We assessed whether supplementation with a blend of krill and salmon (KS) oil [which is rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] affects insulin sensitivity in overweight men.

Design: The design was a randomized, double-blind, controlled crossover trial. A total of 47 men with a mean ± SD age of 46.5 ± 5.1 y, who were overweight [body mass index (in kg/m(2)) from 25 to 30] but otherwise healthy, received 5 1-g capsules of KS oil or a control (canola oil) for 8 wk and crossed over to another treatment after an 8-wk washout period. The primary outcome was insulin sensitivity assessed by using the Matsuda method from an oral-glucose-tolerance test. Secondary outcomes included lipid profiles, inflammatory markers, 24-h ambulatory blood pressure, and carotid artery intimamedia thickness.

Results: Unexpectedly, insulin sensitivity (per the Matsuda index) was 14% lower with the KS oil than with the control oil (P = 0.049). A mediation analysis showed that, after controlling for the likely positive effects of blood EPA and DHA (i.e., the omega-3 index), the reduction in insulin sensitivity after KS-oil supplementation was more marked [27% lower than with the control oil (P = 0.009)].

Conclusions: Supplementation with a blend of KS oil is associated with decreased insulin sensitivity. Thus, krill-oil supplementation in overweight adults could exacerbate risk of diabetes and cardiovascular disease. This trial was prospectively registered at the Australian New Zealand Clinical Trials Registry as ACTRN12611000602921.
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http://dx.doi.org/10.3945/ajcn.114.103028DOI Listing
July 2015

Blood pressure abnormalities in adults born moderately preterm and their children.

Int J Cardiol 2015 Feb 26;181:152-4. Epub 2014 Nov 26.

Liggins Institute, University of Auckland, Auckland, New Zealand; Gravida: National Centre for Growth and Development, Auckland, New Zealand. Electronic address:

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http://dx.doi.org/10.1016/j.ijcard.2014.11.162DOI Listing
February 2015

Increasing parental age at childbirth is associated with greater insulin sensitivity and more favorable metabolic profile in overweight adult male offspring.

Am J Hum Biol 2015 May-Jun;27(3):380-6. Epub 2014 Nov 13.

Liggins Institute, University of Auckland, Auckland, New Zealand.

Objective: To assess the effect of parental age at childbirth on insulin sensitivity and other metabolic outcomes in overweight middle-aged males.

Methods: We studied 73 men aged 46.0±5.4 years, who were overweight (body mass index, BMI 25-30 kg/m(2) ) but otherwise healthy. Insulin sensitivity was assessed by the Matsuda method from an oral glucose tolerance test. Other assessments included dual-energy X-ray absorptiometry-derived body composition, lipid profile, 24-hour ambulatory blood pressure, and carotid intima-media thickness. Maternal and paternal ages were highly correlated (r = 0.71; P < 0.0001), and the main parameter of interest in this study was the mean parental age at childbirth (MPAC), calculated as the average of maternal and paternal ages.

Results: Increasing MPAC was associated with a continuous increase in insulin sensitivity (β = 0.193; P = 0.008), as well as reductions in insulin resistance (HOMA-IR; β = -0.064; P = 0.011), fasting insulin (β = -0.221; P = 0.018) and fasting glucose (β = -0.030; P = 0.033) concentrations. Increasing MPAC was also associated with reductions in night time systolic (β = -0.500; P = 0.020) and diastolic (β = -0.325; P = 0.047) blood pressure, as well as with improved (greater) nocturnal diastolic blood pressure dipping (β = 0.413; P = 0.046). Subgroup analyses on participants of European descent (n = 64) showed that increasing MPAC was associated with reduced carotid intima-media thickness (β = -0.008; P = 0.018) and lower low-density lipoprotein cholesterol concentrations (β = -0.042; P = 0.028).

Conclusions: Increasing parental age at childbirth was associated with a more favorable metabolic phenotype in overweight middle-aged males. However, it is unknown whether the effect was maternal, paternal, or both. Future studies on the effects of parental age at childbirth on the metabolism of males and females across the BMI range are required.
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http://dx.doi.org/10.1002/ajhb.22654DOI Listing
January 2016

Increasing maternal prepregnancy body mass index is associated with reduced insulin sensitivity and increased blood pressure in their children.

Clin Endocrinol (Oxf) 2015 Sep 29;83(3):352-6. Epub 2014 Dec 29.

Liggins Institute, University of Auckland, Auckland, New Zealand.

Objective: We aimed to assess the effects of maternal prepregnancy body mass index (BMI) on insulin sensitivity, metabolism and blood pressure in the offspring.

Methods: We studied 70 prepubertal children aged 8·9 ± 1·9 years (range 4-11 years), born 38-40 weeks of gestation and appropriate-for-gestational-age birthweight. Maternal prepregnancy body mass index (MPP BMI) was calculated from self-reported weight. Children's insulin sensitivity was measured using intravenous glucose tolerance tests and Bergman's minimal model. Other clinical assessments included auxology, fasting lipid and hormonal profiles, DXA-derived body composition and 24-h ambulatory blood pressure monitoring. Data were analysed using random effect mixed models, adjusting for important confounders and a random factor to account for sibling clusters.

Results: Increasing MPP BMI was correlated with increasing BMI standard deviation scores (SDS) (r = 0·30; P = 0·012) and lower insulin sensitivity in their children (r = -0·34; P = 0·004). In multivariate regression models, increasing MPP BMI was associated with lower insulin sensitivity (β = -0·040; P = 0·005), with every 1 kg/m(2) increase in MPP BMI associated with a 4·0% decrease in offspring insulin sensitivity. Greater MPP BMI was associated with higher systolic blood pressure in the daytime (β = 0·794; P = 0·010) and night-time (β = 0·800; P = 0·017), as well as higher 24-h mean arterial pressure (β = 0·508; P = 0·025) in the offspring.

Conclusion: Greater maternal prepregnancy BMI is associated with lower insulin sensitivity and higher blood pressure in their children, effects that were independent of offspring adiposity. Thus, higher maternal BMI prior to pregnancy (even among women of normal BMI) may contribute to increased risk of type 2 diabetes and other metabolic diseases in the subsequent generation.
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http://dx.doi.org/10.1111/cen.12665DOI Listing
September 2015

Higher omega-3 index is associated with increased insulin sensitivity and more favourable metabolic profile in middle-aged overweight men.

Sci Rep 2014 Oct 21;4:6697. Epub 2014 Oct 21.

1] Liggins Institute, University of Auckland, Auckland, New Zealand [2] Gravida: National Centre for Growth and Development, Auckland, New Zealand.

We assessed whether omega-3 index (red blood cell concentrations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)) was associated with insulin sensitivity and other metabolic outcomes in 47 overweight men aged 46.5 ± 5.1 years. Participants were assessed twice, 16 weeks apart. Insulin sensitivity was assessed by the Matsuda method from an oral glucose tolerance test. Linear associations were examined; stratified analyses were carried out with participants separated according to the omega-3 index: lower tertiles (LOI; n = 31) and highest tertile (HOI; n = 16). Increasing omega-3 index was correlated with higher insulin sensitivity (r = 0.23; p = 0.025), higher disposition index (r = 0.20; p = 0.054), and lower CRP concentrations (r = -0.39; p < 0.0001). Insulin sensitivity was 43% higher in HOI than in LOI men (Matsuda index 6.83 vs 4.78; p = 0.009). Similarly, HOI men had disposition index that was 70% higher (p = 0.013) and fasting insulin concentrations 25% lower (p = 0.038). HOI men displayed lower nocturnal systolic blood pressure (-6.0 mmHg; p = 0.025) and greater systolic blood pressure dip (14.7 vs 10.8%; p = 0.039). Men in the HOI group also had lower concentrations of CRP (41% lower; p = 0.033) and free fatty acids (21% lower, p = 0.024). In conclusion, higher omega-3 index is associated with increased insulin sensitivity and a more favourable metabolic profile in middle-aged overweight men.
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http://dx.doi.org/10.1038/srep06697DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5381193PMC
October 2014

Among overweight middle-aged men, first-borns have lower insulin sensitivity than second-borns.

Sci Rep 2014 Feb 6;4:3906. Epub 2014 Feb 6.

1] Liggins Institute, University of Auckland, Auckland, New Zealand [2] Gravida: National Centre for Growth and Development, University of Auckland, Auckland, New Zealand.

We aimed to assess whether birth order affects metabolism and body composition in overweight middle-aged men. We studied 50 men aged 45.6 ± 5.5 years, who were overweight (BMI 27.5 ± 1.7 kg/m(2)) but otherwise healthy in Auckland, New Zealand. These included 26 first-borns and 24 second-borns. Insulin sensitivity was assessed by the Matsuda method from an oral glucose tolerance test. Other assessments included DXA-derived body composition, lipid profiles, 24-hour ambulatory blood pressure, and carotid intima-media thickness. First-born men were 6.9 kg heavier (p = 0.013) and had greater BMI (29.1 vs 27.5 kg/m(2); p = 0.004) than second-borns. Insulin sensitivity in first-born men was 33% lower than in second-borns (4.38 vs 6.51; p = 0.014), despite adjustment for fat mass. There were no significant differences in ambulatory blood pressure, lipid profile or carotid intima-media thickness between first- and second-borns. Thus, first-born adults may be at a greater risk of metabolic and cardiovascular diseases.
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http://dx.doi.org/10.1038/srep03906DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3915551PMC
February 2014

Olive (Olea europaea L.) leaf polyphenols improve insulin sensitivity in middle-aged overweight men: a randomized, placebo-controlled, crossover trial.

PLoS One 2013 13;8(3):e57622. Epub 2013 Mar 13.

Liggins Institute, University of Auckland, Auckland, New Zealand.

Background: Olive plant leaves (Olea europaea L.) have been used for centuries in folk medicine to treat diabetes, but there are very limited data examining the effects of olive polyphenols on glucose homeostasis in humans.

Objective: To assess the effects of supplementation with olive leaf polyphenols (51.1 mg oleuropein, 9.7 mg hydroxytyrosol per day) on insulin action and cardiovascular risk factors in middle-aged overweight men.

Design: Randomized, double-blinded, placebo-controlled, crossover trial in New Zealand. 46 participants (aged 46.4 ± 5.5 years and BMI 28.0 ± 2.0 kg/m(2)) were randomized to receive capsules with olive leaf extract (OLE) or placebo for 12 weeks, crossing over to other treatment after a 6-week washout. Primary outcome was insulin sensitivity (Matsuda method). Secondary outcomes included glucose and insulin profiles, cytokines, lipid profile, body composition, 24-hour ambulatory blood pressure, and carotid intima-media thickness.

Results: Treatment evaluations were based on the intention-to-treat principle. All participants took >96% of prescribed capsules. OLE supplementation was associated with a 15% improvement in insulin sensitivity (p = 0.024) compared to placebo. There was also a 28% improvement in pancreatic β-cell responsiveness (p = 0.013). OLE supplementation also led to increased fasting interleukin-6 (p = 0.014), IGFBP-1 (p = 0.024), and IGFBP-2 (p = 0.015) concentrations. There were however, no effects on interleukin-8, TNF-α, ultra-sensitive CRP, lipid profile, ambulatory blood pressure, body composition, carotid intima-media thickness, or liver function.

Conclusions: Supplementation with olive leaf polyphenols for 12 weeks significantly improved insulin sensitivity and pancreatic β-cell secretory capacity in overweight middle-aged men at risk of developing the metabolic syndrome.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0057622PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3596374PMC
September 2013

Psyllium supplementation in adolescents improves fat distribution & lipid profile: a randomized, participant-blinded, placebo-controlled, crossover trial.

PLoS One 2012 27;7(7):e41735. Epub 2012 Jul 27.

Liggins Institute, University of Auckland, Auckland, New Zealand.

Aims: We aimed to assess the effects of psyllium supplementation on insulin sensitivity and other parameters of the metabolic syndrome in an at risk adolescent population.

Methods: This study encompassed a participant-blinded, randomized, placebo-controlled, crossover trial. Subjects were 47 healthy adolescent males aged 15-16 years, recruited from secondary schools in lower socio-economic areas with high rates of obesity. Participants received 6 g/day of psyllium or placebo for 6 weeks, with a two-week washout before crossing over. Fasting lipid profiles, ambulatory blood pressure, auxological data, body composition, activity levels, and three-day food records were collected at baseline and after each 6-week intervention. Insulin sensitivity was measured by the Matsuda method using glucose and insulin values from an oral glucose tolerance test.

Results: 45 subjects completed the study, and compliance was very high: 87% of participants took >80% of prescribed capsules. At baseline, 44% of subjects were overweight or obese. 28% had decreased insulin sensitivity, but none had impaired glucose tolerance. Fibre supplementation led to a 4% reduction in android fat to gynoid fat ratio (p = 0.019), as well as a 0.12 mmol/l (6%) reduction in LDL cholesterol (p = 0.042). No associated adverse events were recorded.

Conclusions: Dietary supplementation with 6 g/day of psyllium over 6 weeks improves fat distribution and lipid profile (parameters of the metabolic syndrome) in an at risk population of adolescent males.

Trial Registration: Australian New Zealand Clinical Trials Registry ACTRN12609000888268.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0041735PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3407232PMC
April 2013