Alison M. Coates

Effects of n-3 fatty acids, EPA v. DHA, on depressive symptoms, quality of life, memory and executive function in older adults with mild cognitive impairment: a 6-month randomised controlled trial.

Depressive symptoms may increase the risk of progressing from mild cognitive impairment (MCI) to dementia. Consumption of n-3 PUFA may alleviate both cognitive decline and depression. The aim of the present study was to investigate the benefits of supplementing a diet with n-3 PUFA, DHA and EPA, for depressive symptoms, quality of life (QOL) and cognition in elderly people with MCI. We conducted a 6-month double-blind, randomised controlled trial. A total of fifty people aged >65 years with MCI were allocated to receive a supplement rich in EPA (1·67 g EPA + 0·16 g DHA/d; n 17), DHA (1·55 g DHA + 0·40 g EPA/d; n 18) or the n-6 PUFA linoleic acid (LA; 2·2 g/d; n 15). Treatment allocation was by minimisation based on age, sex and depressive symptoms (Geriatric Depression Scale, GDS). Physiological and cognitive assessments, questionnaires and fatty acid composition of erythrocytes were obtained at baseline and 6 months (completers: n 40; EPA n 13, DHA n 16, LA n 11). Compared with the LA group, GDS scores improved in the EPA (P=0·04) and DHA (P=0·01) groups and verbal fluency (Initial Letter Fluency) in the DHA group (P=0·04). Improved GDS scores were correlated with increased DHA plus EPA (r 0·39, P=0·02). Improved self-reported physical health was associated with increased DHA. There were no treatment effects on other cognitive or QOL parameters. Increased intakes of DHA and EPA benefited mental health in older people with MCI. Increasing n-3 PUFA intakes may reduce depressive symptoms and the risk of progressing to dementia. This needs to be investigated in larger, depressed samples with MCI.

Effect of cocoa flavanols and exercise on cardiometabolic risk factors in overweight and obese subjects

Objective:Impaired endothelial function in obesity may reduce blood flow to sites of metabolism, contributing to impaired fat oxidation and insulin resistance. This study investigated the effects of cocoa flavanols and regular exercise, interventions known to improve endothelial function, on cardiometabolic function and body composition in obese individuals.Design:Overweight and obese adults were randomly assigned to high-flavanol cocoa (HF, 902 mg flavanols), HF and exercise, low-flavanol cocoa (LF, 36 mg flavanols), or LF and exercise for 12 weeks (exercise duration was 3 × 45 min per week at 75% of age-predicted maximum heart rate). Body composition was assessed by dual-energy X-ray absorptiometry at 0 and 12 weeks. Brachial artery flow-mediated dilatation (FMD), supine blood pressure (BP) and fasting plasma insulin, and glucose levels were assessed at 0, 6 and 12 weeks, respectively. Insulin sensitivity/resistance was determined using the modified homeostasis model assessment of insulin resistance (HOMA2).Results:A total of 49 subjects (M=18; F=31) completed the intervention. Baseline averages were as follows: body mass index=33.5 kg/m2; BP=123/76 mm Hg; HOMA2=2.4; FMD=4.3%; rate of fat oxidation during exercise=0.34 g min−1; abdominal fat=45.7% of total abdominal mass. Compared to LF, HF increased FMD acutely (2 h post-dose) by 2.4% (P<0.01) and chronically (over 12 weeks; P<0.01) by 1.6% and reduced insulin resistance by 0.31% (P<0.05), diastolic BP by 1.6 mm Hg and mean arterial BP by 1.2 mm Hg (P<0.05), independent of exercise. Regular exercise increased fat oxidation during exercise by 0.10 g min−1 (P<0.01) and reduced abdominal fat by 0.92% (P<0.05).Conclusion:Although HF consumption was shown to improve endothelial function, it did not enhance the effects of exercise on body fat and fat metabolism in obese subjects. However, it may be useful for reducing cardiometabolic risk factors in this population.

Can EGCG Reduce Abdominal Fat in Obese Subjects

Objective: To evaluate metabolic effects of epigallocatechin gallate (EGCG) supplementation when combined with a program of regular aerobic exercise in overweight/obese post-menopausal women. Methods: Thirty-eight overweight or obese postmenopausal women exercised at moderate intensity, viz. walking three times per week for 45 min at 75% of age-predicted maximum heart rate (HR), and took a 150 mg capsule of EGCG (Teavigo®) or placebo (lactose) twice daily for 12 weeks. Blood parameters (lipids, glucose and insulin), blood pressure, heart rate, arterial function and anthropometry were assessed at 0, 6 and 12 wk. At wk 0 and 12, body composition was assessed by dual energy X-ray absorptiometry (DXA) and abdominal fat was assessed by DXA and computed tomography (CT). Results: Waist circumference (p < 0.01), total body fat (p < 0.02), abdominal fat (by DXA) (p < 0.01) and intra abdominal adipose tissue (by CT) (p < 0.01) were reduced in both treatment groups, with no difference between placebo and Teavigo®. Teavigo® significantly decreased resting HR (p < 0.01) and reduced plasma glucose in subjects with impaired glucose tolerance (p < 0.05). Conclusions: Moderate consumption of EGCG can improve the health status of overweight individuals undergoing regular exercise by reducing HR and plasma glucose concentrations. Loss of body fat, however, may require a higher intake of EGCG, other catechins or addition of metabolic stimulants.

Treatment of adolescent overweight and obesity

Adolescence is a vulnerable period for the development of obesity, and adolescent weight tracks strongly into adulthood. Previous reviews of treatment strategies have failed to discriminate between adolescents and children, thereby, disregarding the uniqueness of this population. Hence, this review aims to summarise the evidence for treatment approaches for adolescent obesity. Pubmed, OVID, EBSCOhost and Google Scholar were searched for randomised controlled trials, meta-analyses and systematic reviews testing treatments for overweight/obese adolescents (aged 12–19 years), published from 1982–2006 in English. Eligible studies had to assess either weight, percentage overweight, body mass index (BMI) or body fat. Thirty-four randomised controlled trials were eligible. The results of this review indicate that the safety and efficacy of surgical and pharmacotherapy treatments for adolescent obesity is uncertain. Diet and physical activity approaches may improve obese status in the short term. However, obesity interventions appear more effective when strategies are combined, rather than when used in isolation. Psychological interventions, such as behavioural and cognitive behavioural therapy, show promise in achieving the necessary lifestyle changes for obesity reduction; however, long-term follow-up studies are needed. There were multiple limitations in appraising the literature. Inconsistent definitions of overweight/obesity make comparisons between studies difficult. Many studies have not used direct adiposity measures, have failed to assess pubertal status or have not used an exclusive adolescent sample. We conclude that, despite these limitations, current evidence indicates that behavioural and cognitive behavioural strategies combined with diet and physical activity approaches may assist in reducing adolescent obesity,although long-term follow-up studies are needed.

Supplementation with a whey protein hydrolysate enhances recovery of muscle force-generating capacity following eccentric exercise.

There is evidence that protein hydrolysates can speed tissue repair following damage and may therefore be useful for accelerating recovery from exercise induced muscle damage. The potential for a hydrolysate (WPI(HD)) of whey protein isolate (WPI) to speed recovery following eccentric exercise was evaluated by assessing effects on recovery of peak isometric torque (PIT). In a double-blind randomised parallel trial, 28 sedentary males had muscle soreness (MS), serum creatine kinase (CK) activity, plasma TNFalpha, and PIT assessed at baseline and after 100 maximal eccentric contractions (ECC) of their knee extensors. Participants then consumed 250 ml of flavoured water (FW; n=11), or FW containing 25 g WPI (n=11) or 25 g WPI(HD) (n=6) and the assessments were repeated 1, 2, 6 and 24h later. PIT decreased approximately 23% following ECC, remained suppressed in FW and WPI, but recovered fully in WPI(HD) by 6h (P=0.006, treatment x time interaction). MS increased following ECC (P<0.001 for time), and remained elevated with no difference between groups (P=0.61). TNFalpha and CK did not change (P>0.45). WPI(HD) may be a useful supplement for assisting athletes to recover from fatiguing eccentric exercise.

Loss of skeletal muscle mass after stroke: a systematic review.

Loss of muscle mass after stroke has implications for strength and functional ability and may also contribute to impaired glucose metabolism. Therefore, prevention of muscle loss is desirable. Before interventions to prevent loss of muscle can be designed and evaluated, the expected rate, magnitude and timing of muscle loss need to be understood. A systematic search was undertaken to identify all studies that investigated changes in skeletal muscle mass, volume or cross-sectional area in people after stroke. Studies that used either direct measures of muscle size (computer tomography, magnetic resonance imaging or ultrasound) or measures of lean tissue mass (dual X-ray absorptiometry) were included. Fourteen trials were found and the results were pooled for differences in lean tissue mass between the paretic and the nonparetic leg and arm as well as differences in the midthigh cross-sectional area. In individuals at least 6-month post-stroke, there was significantly less lean tissue mass in the paretic compared with the nonparetic lower limb (MD 342.3 g, 95% confidence interval 247.0–437.6 g) and upper limb (MD 239.9 g, 95% confidence interval 181.7–298.2 g), and significantly less midthigh muscle cross-sectional area (MD 15.4 cm2, 95% confidence interval 13.8–16.9 cm2). There were insufficient data to pool with regard to change in muscle mass over time. There is a significant difference in the regional muscle mass in the paretic vs. the nonparetic limb in individuals greater than 6-months poststroke but little is known about how early and how quickly changes in muscle mass occur.

Chronic resveratrol consumption improves brachial flow-mediated dilatation in healthy obese adults.

Background: We have previously demonstrated acute dose-dependent increases of flow-mediated dilatation (FMD) in the brachial artery after resveratrol consumption in mildly hypertensive, overweight/obese adults. Resveratrol supplementation has also been shown to increase cerebral blood flow acutely, without affecting cognition. Objectives: To evaluate the effects of chronic resveratrol supplementation on both FMD and cognitive performance. Method: Twenty-eight obese but otherwise healthy adults (BMI: 33.3 ± 0.6 kg/m2) were randomized to take a single 75 mg capsule of trans-resveratrol (Resvida) or placebo daily for 6 weeks each in a double-blind crossover supplementation trial. Blood pressure, arterial compliance, FMD, and performance on the Stroop Color-Word Test were assessed at the end of each 6-week intervention period while fasted and at least 18 h after taking the last daily capsule. An additional capsule of the same supplement was then taken. FMD assessment was repeated 1 h later. Results: Chronic resveratrol supplementation for 6 weeks was well tolerated and resulted in a 23% increase in FMD compared with placebo (P = 0.021, paired t-test). The extent of increase correlated negatively with baseline FMD (r = −0.47, P = 0.01). A single dose of resveratrol (75 mg) following chronic resveratrol supplementation resulted in a 35% greater acute FMD response than the equivalent placebo supplementation. These FMD improvements remained significant after adjusting for baseline FMD. Blood pressure, arterial compliance, and all components of the Stroop Color-Word Test were unaffected by chronic resveratrol supplementation. Conclusion: Daily resveratrol consumption was well tolerated and has the potential to maintain healthy circulatory function in obese adults.

Estimating Abdominal Adipose Tissue with DXA and Anthropometry

Objective: To identify an anatomically defined region of interest (ROI) from DXA assessment of body composition that when combined with anthropometry can be used to accurately predict intra‐abdominal adipose tissue (IAAT) in overweight/obese individuals.

Obesity: the new childhood disability?

This review addresses the impact of obesity on paediatric physical functioning utilizing the World Health Organization International Classification of Functioning, Disability and Health Framework (ICF). The ICF encompasses functioning (as it relates to all body functions and structures), activities (undertaking a particular task) and participation (in a life situation) with disability referring to impairments in body functions/structures, activity restrictions or participation limitations. Electronic databases were searched for peer‐reviewed studies published in English prior to May 2009 that examined aspects of physical functioning in children (≤18 years). Eligible studies (N = 104) were ranked by design and synthesized descriptively. Childhood obesity was found to be associated with deficits in function, including impaired cardiorespiratory fitness and performance of motor tasks; and there was some limited evidence of increased musculoskeletal pain and decrements in muscle strength, gait and balance. Health‐related quality of life and the subset of physical functioning was inversely related to weight status. However, studies investigating impacts of obesity on wider activity and participation were lacking. Further research utilizing the ICF is required to identify and better characterize the effects of paediatric obesity on physical function, activity and participation, thereby improving targets for intervention to reduce disability in this population.

Dairy consumption and cardiometabolic health: outcomes of a 12-month crossover trial.

BackgroundA growing body of research suggests that regular consumption of dairy foods may counteract obesity and other components of the metabolic syndrome. However, human intervention trials are lacking. We aimed to determine the cardiometabolic health effects of increasing the consumption of reduced fat dairy foods in adults with habitually low dairy intakes in the absence of energy restriction.MethodsAn intervention trial was undertaken in 61 overweight or obese adults who were randomly assigned to a high dairy diet (HD, 4 serves of reduced fat dairy/day) or a low dairy control diet (LD, ≤1 serve/day) for 6 months then crossed over to the alternate diet for a further 6 months. A range of anthropometric and cardiometabolic parameters including body composition, metabolic rate, blood lipids, blood pressure and arterial compliance were assessed at the end of each diet phase.ResultsTotal energy intake was 1120 kJ/day higher during the HD phase, resulting in slight weight gain during this period. However, there were no significant differences between HD and LD in absolute measures of waist circumference, body weight, fat mass or any other cardiometabolic parameter.ConclusionRecommended intakes of reduced fat dairy products may be incorporated into the diet of overweight adults without adversely affecting markers of cardiometabolic health.Trial RegistrationThe trial was registered with the Australia and New Zealand Clinical Trials Registry (ACTRN12608000538347) on 24th October, 2008.