Long-term effects of very low-carbohydrate and high-carbohydrate weight-loss diets on psychological health in obese adults with type 2 diabetes: randomized controlled trial.

BACKGROUND/OBJECTIVE: Very low-carbohydrate, high-fat (LC) diets are used for type 2 diabetes (T2DM) management, but their effects on psychological health remain largely unknown. This study examined the long-term effects of an LC diet on psychological health. METHODS: One hundred and fifteen obese adults [age: 58.5 ± 7.1 years; body mass index: 34.6 ± 4.3 kg m(-2) ; HbA1c : 7.3 ± 1.1%] with T2DM were randomized to consume either an energy-restricted (~6 to 7 MJ), planned isocaloric LC or high-carbohydrate, low-fat (HC) diet, combined with a supervised exercise programme (3 days week(-1) ) for 1 year. Body weight, psychological mood state and well-being [Profile of Mood States (POMS), Beck Depression Inventory (BDI) and Spielberger State Anxiety Inventory (SAI)] and diabetes-specific emotional distress [Problem Areas in Diabetes (PAID) Questionnaire] and quality of life [QoL Diabetes-39 (D-39)] were assessed. RESULTS: Overall weight loss was 9.5 ± 0.5 kg (mean ± SE), with no difference between groups (P = 0.91 time × diet). Significant improvements occurred in BDI, POMS (total mood disturbance and the six subscales of anger-hostility, confusion-bewilderment, depression-dejection, fatigue-inertia, vigour-activity and tension-anxiety), PAID (total score) and the D-39 dimensions of diabetes control, anxiety and worry, sexual functioning and energy and mobility, P < 0.05 time. SAI and the D-39 dimension of social burden remained unchanged (P ≥ 0.08 time). Diet composition had no effect on the responses for the outcomes assessed (P ≥ 0.22 time × diet). CONCLUSION: In obese adults with T2DM, both diets achieved substantial weight loss and comparable improvements in QoL, mood state and affect. These results suggest that either an LC or HC diet within a lifestyle modification programme that includes exercise training improves psychological well-being.

Short communication: a food-systems approach to assessing dairy product waste.

Concern about world population increase, food security, and the environmental burdens of food production have made food-waste reduction a social and environmental priority. In this context, the quantification of dairy product waste is especially difficult due to the varied means of disposal, by solid and liquid waste streams, and due to inclusion as an ingredient in many processed foods. In this study, food intake data from the Australian National Nutrition Survey (>13,000 participants; >4,500 food items) were disaggregated into basic foods and total national dairy product intake was expressed in whole-milk equivalents. This result was compared with total domestic milk supply, indicating a level of waste of 29% for dairy products in the Australian food system. With national food-waste reduction targets becoming increasingly common, reliable estimates of food waste at the national scale are important for goal setting, baseline reporting, and performance monitoring. For this purpose, the systems approach to assessing food waste demonstrated in this project is deemed to have advantages over other common methods of food-waste assessment, such as bin audits, waste diaries, and surveys.

Sex hormone binding globulin, but not testosterone, is associated with the metabolic syndrome in overweight and obese women with polycystic ovary syndrome.

BACKGROUND: Polycystic ovary syndrome (PCOS) is associated with hyperandrogenism and an increased risk of Type 2 diabetes and cardiovascular disease. Decreased SHBG and elevated testosterone are associated with metabolic syndrome and glucose intolerance in women. AIM: The aim of this study was to assess the relationship between SHBG and testosterone and metabolic syndrome and glucose intolerance in PCOS. MATERIAL/SUBJECTS AND METHODS: Cross-sectional study in overweight and obese premenopausal non-diabetic women with PCOS (no.=178: no.=55 metabolic syndrome, no.=16 glucose intolerance). Data were analyzed by multiple regression with metabolic syndrome, oral glucose tolerance test (OGTT) glucose or SHBG as dependent variables and reproductive hormones, insulin resistance, glucose tolerance, lipids or C-reactive protein as independent variables. RESULTS: Metabolic syndrome was independently associated with body mass index [odds ratio (OR) 1.084 95% confidence interval (CI) 1.034-1.170, p=0.015] and SHBG (OR 0.961 95% CI 0.932-0.995, p=0.018). Glucose tolerance was independently associated with OGTT insulin (ß=0.418, p<0.001), age (ß=0.154, p=0.033) and PRL (ß=-0.210, p=0.002). SHBG was independently associated with OGTT insulin (ß=-0.216, p=0.014) and PCOS diagnostic criteria (ß=0.197, p=0.010). CONCLUSIONS: SHBG, but not testosterone, is independently associated with metabolic syndrome in overweight women with PCOS and is associated with insulin resistance and PCOS diagnostic criteria.

The effect of diet and exercise on markers of endothelial function in overweight and obese women with polycystic ovary syndrome.

BACKGROUND: Women with polycystic ovary syndrome (PCOS) present with vascular abnormalities, including elevated markers of endothelial dysfunction. There is limited evidence for the effect of lifestyle modification and weight loss on these markers. The aim of this study was to determine if 20 weeks of a high-protein energy-restricted diet with or without exercise in women with PCOS could improve endothelial function. METHODS: This is a secondary analysis of a subset of 50 overweight/obese women with PCOS (age: 30.3 ± 6.3 years; BMI: 36.5 ± 5.7 kg/m(2)) from a previous study. Participants were randomly assigned by computer generation to one of three 20-week interventions: diet only (DO; n = 14, ≈ 6000 kJ/day), diet and aerobic exercise (DA; n = 16, ≈ 6000 kJ/day and five walking sessions/week) and diet and combined aerobic-resistance exercise (DC; n = 20, ≈ 6000 kJ/day, three walking and two strength sessions/week). At Weeks 0 and 20, weight, markers of endothelial function [vascular cell adhesion molecule-1 (sVCAM-1), inter-cellular adhesion molecule-1 (sICAM-1), plasminogen activator inhibitor-1 (PAI-1) and asymmetric dimethylarginine (ADMA)], insulin resistance and hormonal profile were assessed. RESULTS: All three treatments resulted in significant weight loss (DO 7.9 ± 1.2%, DA 11.0 ± 1.6%, DC 8.8 ± 1.1; P < 0.001 for time; P = 0.6 time × treatment). sVCAM-1, sICAM-1 and PAI-1 levels decreased with weight loss (P≤ 0.01), with no differences between treatments (P ≥ 0.4). ADMA levels did not change significantly (P = 0.06). Testosterone, sex hormone-binding globulin and the free androgen index (FAI) and insulin resistance also improved (P < 0.001) with no differences between treatments (P ≥ 0.2). Reductions in sVCAM-1 were correlated to reductions in testosterone (r = 0.32, P = 0.03) and FAI (r = 0.33, P = 0.02) as well as weight loss (r= 0.44, P = 0.002). Weight loss was also associated with reductions in sICAM-1 (r= 0.37, P = 0.008). CONCLUSIONS: Exercise training provided no additional benefit to following a high-protein, hypocaloric diet on markers of endothelial function in overweight/obese women with PCOS.

Self-reported facilitators of, and impediments to maintenance of healthy lifestyle behaviours following a supervised research-based lifestyle intervention programme in patients with type 2 diabetes.

INTRODUCTION: Sustainability of healthy lifestyle behaviours following participation in a research-based supervised lifestyle intervention programme is often poor. This study aimed to document factors reported by overweight and obese individuals with Type 2 diabetes as enhancing or impeding sustainability of lifestyle behaviours following participation in such a programme. METHODS: Thirty patients who completed a 16-week research-based supervised lifestyle intervention programme, incorporating a structured energy restricted diet with or without supervised resistance-exercise training underwent a semi-structured qualitative interview about their experiences in maintaining programme components after 1 year. RESULTS: Participants maintained 8.8 ± 8.9 kg of the 13.9 ± 6.6 kg weight loss achieved with the research-based supervised lifestyle intervention programme. Only 23% of participants indicated continuation of the complete diet programme. Desire for 'variety' (33%) and increased portion size (27%) were the most commonly reported reasons for discontinuation. Participants who undertook supervised exercise training during the programme indicated access to appropriate programmes/facilities (38%), more affordable gym membership (21%) and having a personal trainer/motivator (17%) would have facilitated exercise continuation. CONCLUSION: In overweight and obese individuals with Type 2 diabetes, success of the research-based supervised lifestyle intervention programme was perceived as being primarily due to high levels of professional support and supervision, the discontinuation of which subsequently presented difficulties. The interview data provide insight into what people experience following the completion of a research-based intensive lifestyle intervention programme and suggest that programmes assembled for research purposes with the emphasis on compliance may not necessarily promote sustainable change.

The effect of comprehensive lifestyle intervention or metformin on obesity in young women.

BACKGROUND AND AIM: Young women are at high risk of weight gain but few weight management interventions have been investigated in this group. This study aimed to determine the effect of metformin on body weight, body composition, metabolic risk factors and reproductive hormone levels in overweight or obese young women compared to placebo and comprehensive lifestyle intervention. METHODS AND RESULTS: 203 overweight or obese young women (BMI 33.2+/-0.3 kg/m², age 28+/-0.3 years) were randomised to 1500 mg/day metformin (M) plus general lifestyle advice, placebo (P) plus general lifestyle advice or comprehensive lifestyle intervention including structured diet, exercise and behavioural therapy (L) for 12-weeks. At 12-weeks, linear mixed models found that L group had greater weight loss (-4.2+/-0.4 kg) compared to M (-1.0+/-0.4 kg) and P groups (-0.2+/-0.3 kg) (P < 0.0001). Weight loss between M and P groups were not significantly different. Attrition rate was 48% for L, 34% for M and 29% for P (P = 0.08). Intention-to-treat analysis showed that 10% (8/79) of the subjects in P group had gained weight (>3%), compared to 3% (2/65) from M group and none (0/59) from L group (P < 0.001). The L group had the greatest decrease in waist circumference (-5.2+/-0.7 cm) and fat mass (-5.4+/-0.7 kg) compared to the other groups (P < 0.05). No significant time-by-group effects were seen in plasma lipids, SHBG, testosterone, blood pressure, serum folate, serum ferritin and serum vitamin B12. CONCLUSION: Lifestyle intervention was more effective in reducing body weight and improving body composition compared to metformin among healthy overweight or obese young women.

A pilot comprehensive lifestyle intervention program (CLIP)--comparison with qualitative lifestyle advice and simvastatin on cardiovascular risk factors in overweight hypercholesterolaemic individuals.

BACKGROUND AND AIMS: Escalating costs of pharmaceuticals for cardiovascular management highlight the need to develop effective lifestyle intervention programs to reduce reliance on these agents. The aim of this pilot study was to evaluate the efficacy of a Comprehensive Lifestyle Intervention Program (CLIP) compared with qualitative lifestyle advice (L) and Simvastatin plus qualitative lifestyle (S+L) on cardiovascular risk factors. METHODS AND RESULTS: Sixty-five overweight adults with hypercholesterolemia were randomised to either L (qualitative advice on diet, exercise), S+L (20 mg/day Simvastatin plus L) or CLIP (6500 kJ structured menu plan: conventional and functional foods contributing <10% energy from saturated fat, ≥3 g soluble fibre, 2.4 g plant sterols, oily fish ≥2 times/week at lunch and dinner, plus exercise advice and self monitoring) for 6 weeks. LDL-cholesterol was lowered in CLIP (-0.57±0.67 mmol/L, 15%) and S+L (-1.43±0.59 mmol/L, 37%), but did not change significantly in L (-0.17±0.59, 4%) (P<0.001 time-by-treatment interaction). Weight and waist circumference were significantly lowered by CLIP (-4.2±2.2 kg; -5.1±2.3 cm) compared to L (-1.0±1.6 kg; -2.7±3.3 cm) and L+S (-0.7±1.4 kg; -2.4±2.3 cm), (P≤0.003 time-by-treatment interactions). B-carotene levels within treatment groups did not change over time and were not lowered by the CLIP diet compared to L (P>0.05, all). Blood pressure changes were not different between groups. CONCLUSIONS: The structured CLIP program was more effective than qualitative lifestyle advice in improving weight, waist circumference and LDL-cholesterol without adverse effects on plasma carotenoids over a 6 week period. This program may therefore assist in comprehensive risk factor management, although the sustainability of these benefits needs confirmation.

Long-term effects of weight loss with a very low carbohydrate and low fat diet on vascular function in overweight and obese patients.

OBJECTIVE: To compare the effects of an energy reduced very low carbohydrate, high saturated fat diet (LC) and an isocaloric high carbohydrate, low fat diet (LF) on endothelial function after 12 months. DESIGN AND SUBJECTS: Forty-nine overweight or obese patients (age 50.0 +/- 1.1 years, BMI 33.7 +/- 0.6 kg m(-2)) were randomized to either an energy restricted ( approximately 6-7 MJ), planned isocaloric LC or LF for 52 weeks. Body weight, endothelium-derived factors, flow-mediated dilatation (FMD), adiponectin, augmentation index (AIx) and pulse wave velocity (PWV) were assessed. All data are mean +/- SEM. RESULTS: Weight loss was similar in both groups (LC -14.9 +/- 2.1 kg, LF -11.5 +/- 1.5 kg; P = 0.20). There was a significant time x diet effect for FMD (P = 0.045); FMD decreased in LC (5.7 +/- 0.7% to 3.7 +/- 0.5%) but remained unchanged in LF (5.9 +/- 0.5% to 5.5 +/- 0.7%). PWV improved in both groups (LC -1.4 +/- 0.6 m s(-1), LF -1.5 +/- 0.6 m s(-1); P = 0.001 for time) with no diet effect (P = 0.80). AIx and VCAM-1 did not change in either group. Adiponectin, eSelectin, tPA and PAI-1 improved similarly in both groups (P < 0.01 for time). CONCLUSION: Both LC and LF hypoenergetic diets achieved similar reductions in body weight and were associated with improvements in PWV and a number of endothelium-derived factors. However, the LC diet impaired FMD suggesting chronic consumption of a LC diet may have detrimental effects on endothelial function.

Timing of protein ingestion relative to resistance exercise training does not influence body composition, energy expenditure, glycaemic control or cardiometabolic risk factors in a hypocaloric, high protein diet in patients with type 2 diabetes.

AIM: To investigate timing of protein ingestion relative to resistance exercise training (RT) on body composition, cardiometabolic risk factors, glycaemic control and resting energy expenditure (REE) during weight loss on a high-protein (HP) diet in overweight and obese patients with type 2 diabetes (T2DM). METHODS: Thirty-four men/women with T2DM (age 57 ± 7 years and body mass index 34.9 ± 4.2 kg m(-2) ) were randomly assigned to the ingestion of a HP meal (860 kJ, 21 g protein, 0.7 g fat, 29.6 g carbohydrate) either immediately prior to RT or at least 2 h following RT. All participants followed a 16-week, energy-restricted (6-7 MJ day(-1) ), HP diet (carbohydrate : protein : fat 43 : 33 : 22) and participated in supervised RT (3 day week(-1) ). Outcomes were assessed pre- and postintervention at 16 weeks. RESULTS: There was an overall reduction in bodyweight (-11.9 ± 6.1 kg), fat mass (-10.0 ± 4.4 kg), fat-free mass (-1.9 ± 3.1 kg), waist circumference (-12.1 ± 5.3 cm), REE (-742 ± 624 kJ day(-1) ), glucose (-1.9 ± 1.7 mmol l(-1) ), insulin (-6.1 ± 6.7 mU l(-1) ) and glycosylated haemoglobin (-1.1 ± 0.1%), p ≤ 0.01 time for all variables, with no difference between groups (p ≥ 0.41 group effect). Strength improved and cardiometabolic risk factors were reduced similarly in both groups; single repetition maximum chest press 11.0 ± 8.7 kg, single repetition maximum lat pull down 9.9 ± 6.0 kg, total cholesterol -0.6 ± 0.5 mmol l(-1) , high-density lipoprotein cholesterol -0.1 ± 0.2 mmol l(-1) , low-density lipoprotein cholesterol -0.3 ± 0.5 mmol l(-1) , triglycerides -0.6 ± 0.7 mmol l(-1) , blood pressure (systolic/diastolic) -13 ± 10/-7 ± 7 mmHg (p ≤ 0.04 time effect, p ≥ 0.24 group effect). CONCLUSION: A HP, energy-restricted diet with RT was effective in improving glycaemic control, body composition, strength and cardiometabolic risk factors in overweight/obese patients with T2DM irrespective of altering the timing of protein ingestion relative to RT.

Long-term effects of a low carbohydrate, low fat or high unsaturated fat diet compared to a no-intervention control.

BACKGROUND AND AIM: Very low carbohydrate ad libitum diets have been shown to enhance weight loss without increasing cardiometabolic risk factors but no kilojoule-controlled trials have been conducted relative to no intervention. The aim of this study was to compare the changes in weight and other cardiovascular risk factors in 3 isocaloric energy-restricted diets to no-intervention control after 1 year. METHODS AND RESULTS: One hundred and thirteen subjects (age 47 ± 10 years, BMI 32 ± 6 kg/m(2) with one additional cardiovascular risk factor) were randomly allocated to one of three isocaloric diets (VLC-very low carbohydrate, 60% fat, 4% carbohydrate, n=30; VLF-very low fat, 10% fat, n = 30; HUF-high unsaturated fat, 30% fat, n = 30) with intensive support for 3 months followed by minimal support for 12 months compared to a control group (no intervention, n = 23). The estimated weight change was -3.0 ± 0.2 kg for VLC, -2.0 ± 0.1 kg for VLF, -3.7 ± 0.01 kg for HUF and 0.8 ± 0.5 kg for controls (P=0.065). After correcting for baseline values, decreases in body weight and diastolic blood pressure in the diet groups (-2.9 ± 5.2) were significantly different to the increase in the control group (0.8 ± 5.0) (P<0.05). No differences in cardiovascular risk factors were observed between the diet groups. CONCLUSION: Significant cardiometabolic risk factor reduction was observed equally with VLC, VLF and HUF diets after 15 months, compared to an exacerbation of risk factors in the control group. At a modest level of adherence, 3 months of intensive support on these dietary patterns confer an improvement in cardiometabolic profile compared to no dietary intervention after 15 months.

The effect of weight loss on anti-Müllerian hormone levels in overweight and obese women with polycystic ovary syndrome and reproductive impairment.

BACKGROUND: Anti-Müllerian hormone (AMH) has been proposed as a clinical predictor of improvements in reproductive function following weight loss in overweight and obese women with polycystic ovary syndrome (PCOS). This study aimed to assess whether baseline and/or change in AMH levels with weight loss predict improvements in reproductive function in overweight and obese women with PCOS. METHODS: Fifty-two overweight and obese women with PCOS and reproductive impairment (age 29.8 +/- 0.8 years, BMI 36.5 +/- 0.7 kg/m(2)) followed a 20-week weight loss programme. AMH, weight, menstrual cyclicity and ovulatory function were assessed at baseline and post-intervention. RESULTS: Participants who responded with improvements in reproductive function (n = 26) had lower baseline AMH levels (23.5 +/- 3.7 versus 32.5 +/- 2.9 pmol/l; P = 0.03) and experienced greater weight loss (-11.7 +/- 1.2 versus -6.4 +/- 0.9 kg; P = 0.001) compared with those who did not respond (n = 26). Logistic regression analysis showed that weight loss and baseline AMH were independently related to improvements in reproductive function (P = 0.002 and P = 0.013, respectively). AMH levels did not change with weight loss in both responders and non-responders. CONCLUSIONS: In overweight and obese women with PCOS and reproductive dysfunction, a 20-week weight loss intervention resulted in improvements in reproductive function but no change in AMH levels. CLINICAL TRIALS REGISTRATION NUMBER: ACTRN12606000198527.

Comparison of aerobic exercise capacity and muscle strength in overweight women with and without polycystic ovary syndrome.

OBJECTIVE: To assess maximal aerobic capacity (VO2max) and muscle strength in overweight and obese women with polycystic ovary syndrome (PCOS) and determine their relationship with metabolic and hormonal factors. DESIGN: Cross-sectional study. SETTING: Clinical Research Unit. POPULATION: Overweight and obese women with PCOS (n = 10) and age-and weight-matched healthy controls (n = 16). METHODS: VO2max was measured during an incremental treadmill test and maximal isometric (ImS) and isokinetic knee extensor strength (IkS) (120 degrees/second) were assessed by isokinetic dynamometry. MAIN OUTCOME MEASURES: VO2max, ImS, IkS, waist circumference, blood lipids, glucose, insulin, insulin resistance (homeostatic model assessment [HOMA2]), C-reactive protein (CRP), hormonal profile. RESULTS: PCOS women had higher levels of testosterone and free testosterone (P < or = 0.05), but there were no significant differences in any cardiovascular disease (CVD) risk markers between the groups. VO2max was similar in women with PCOS and healthy controls (PCOS 26.0 +/- 4.1 ml/kg/minute, controls 25.7 +/- 3.8 ml/kg/minute; P = 0.90), as was ImS (PCOS 1.50 +/- 0.54 Nm/kg, controls 1.50 +/- 0.47 Nm/kg; P = 0.96) and IkS (PCOS 1.04 +/- 0.32 Nm/kg, controls 1.16 +/- 0.23 Nm/kg; P = 0.32). VO2max was inversely related to waist circumference, insulin, HOMA2 and CRP. Waist circumference was inversely associated with ImS and IkS. No significant associations between exercise parameters and hormonal variables were identified. CONCLUSIONS: Compared to age- and weight-matched healthy overweight and obese women with similar insulin resistance and CVD risk profiles, women with PCOS had similar aerobic capacity and muscle strength. This suggests PCOS, at least in the absence of an adverse metabolic profile is unlikely to limit physical function. Larger studies examining the effects of PCOS on exercise tolerance in a diverse range of PCOS phenotypes is required.

Effect of caloric restriction with and without exercise training on oxidative stress and endothelial function in obese subjects with type 2 diabetes.

AIM: Effects of dietary weight loss on endothelial function, particularly when combined with exercise training, is largely unknown in type 2 diabetes. We sought to determine whether aerobic exercise training provided any additional improvements in endothelial function, oxidative stress or other established markers of cardiovascular risk when combined with an energy-restricted diet in patients with type 2 diabetes. METHODS: In a parallel study design, 29 sedentary, overweight and obese patients with type 2 diabetes (age 52.4 +/- 1.4 years and BMI 34.2 +/- 0.9 kg/m(2)) were randomized to a 12-week moderate energy-restricted diet (~5000 kJ/day and approximately 30% energy deficit) with or without aerobic exercise training [diet only (D), n = 16 and diet plus exercise (DE), n = 13]. Body weight, cardiovascular risk markers, malondialdehyde (MDA, oxidative stress marker), 24-h urinary nitrate/nitrite and flow-mediated dilatation (FMD) of the brachial artery were measured pre- and postintervention. RESULTS: Both interventions reduced body weight (D 8.9%, DE 8.5%, time effect p < 0.001). Significant reductions in body fat, waist circumference, blood pressure, glycated haemoglobin, glucose, insulin resistance, lipids and MDA and increases in urinary nitrite/nitrate were observed in both groups (time effect p < or = 0.05); however, these changes were not different between treatments. At baseline, FMD was similar in both groups (D 2.5 +/- 0.9%, DE 4.2 +/- 1.2%; p = 0.25) and did not change after the interventions (p = 0.59). CONCLUSIONS: These results suggest that lifestyle interventions incorporating diet with or without exercise improve glycaemic control, reduce oxidative stress and improve other cardiovascular risk factors but do not improve FMD in obese subjects with type 2 diabetes.

Effects of meals with high soluble fibre, high amylose barley variant on glucose, insulin, satiety and thermic effect of food in healthy lean women.

OBJECTIVE: To examine the effect of barley flour (barley cultivar, Hordeum Vulgare var Himalaya 292) incorporated into breakfast and lunch compared with otherwise identical meals containing white wheat flour on the thermic effect of food (TEF), subsequent food intake and metabolic parameters. DESIGN: Randomized single blinded crossover study. SETTING: Outpatient setting. SUBJECTS AND METHODS: Fourteen healthy women consumed a test breakfast at 0700 h. Energy expenditure, respiratory quotient (RQ), appetite ratings using a visual analogue scale (VAS), insulin and glucose levels were measured before and after a test lunch at 1330 h. Food intake was recorded for the remainder of the day. RESULTS: The TEF was 5% for both test lunches and meal type did not affect any variable measured by the VAS. There was an increase in post-prandial RQ above baseline (0.80) independent of treatment (0.88 and 0.90 for barley and wheat-containing meals, respectively, P<0.001). Mean area under the glycaemic response curve (AUC) for wheat-containing meals was 4.68+/-1.67 mmol/l/h, 22% higher than for the barley-containing meals (3.67+/-1.91 mmol/l/h), P=0.05. AUC of insulin in response to wheat-containing meals (78.1+/-35.3 mIU/l/h) was 32% greater than barley-containing meals (52.8+/-24.7 mU/l/h), P<0.02. Ad libitum food intake over the next 10 h was reduced by 23% (9.6 vs 11.0 MJ, P<0.05) after the wheat-containing meals compared to the barley-containing glycaemic index meals. CONCLUSION: Inclusion of an ingredient containing increased soluble fibre and amylose did not reduce spontaneous food intake but rather was associated with higher subsequent energy intakes despite its reduced glycaemic and insulinemic effects. SPONSORSHIP: CSIRO, Human Nutrition, Adelaide, Australia.

Energy restriction and weight loss on very-low-fat diets reduce C-reactive protein concentrations in obese, healthy women.

C-reactive protein (CRP) is an inflammatory-response protein that is a strong, independent predictor of cardiovascular mortality. CRP is positively associated with body mass index (BMI). In this study, we investigated the effects of dynamic weight loss on CRP in 83 healthy, obese women (mean BMI, 33.8+/-0.4 kg/m(2); range, 28.2 to 43.8 kg/m(2)). Subjects were placed on very-low-fat, energy-restricted diets (5700 kJ, 15% fat) for 12 weeks. Weight, waist and hip circumferences, plasma lipids, glucose, and CRP were measured at baseline and after 12 weeks. CRP was positively associated with BMI (r=0.281, P=0.01) and waist circumference (r=0.278, P=0.01) but was not related to other atherosclerosis risk factors. BMI was significantly different between groups split above or below the median for CRP (34.8+/-0.6 kg/m(2) vs 33.0+/-0.5 kg/m(2), P=0.02). After 12 weeks, weight loss was 7.9+/-0.3 kg. CRP was significantly decreased by 26% (P<0.001), and a correlation was observed between weight loss and the change in CRP (r=0.309, P=0.005). The variance in the change in CRP was partly explained by initial CRP (13.6%), energy intake (5.4%), and percentage weight loss (4.6%, P=0.001). This study confirms recent observations that BMI is associated with CRP, a marker for low-grade systemic inflammation. Furthermore, we observed that CRP was lowered in proportion to weight loss.

Effect of energy restriction, weight loss, and diet composition on plasma lipids and glucose in patients with type 2 diabetes.

OBJECTIVE: To determine the optimal diet for improving glucose and lipid profiles in obese patients with type 2 diabetes during moderate energy restriction. RESEARCH DESIGN AND METHODS: A total of 35 free-living obese patients with type 2 diabetes were assigned to one of three 1,600 kcal/day diets for 12 weeks. The diets were high carbohydrate (10% fat, 4% saturated), high monounsaturated fat (MUFA) (32% fat, 7% saturated), or high saturated fat (SFA) (32% fat, 17% saturated). RESULTS: Diet composition did not affect the magnitude of weight loss, with subjects losing an average of 6.6 +/- 0.9 kg. Energy restriction and weight loss resulted in reductions in fasting plasma glucose (-14%), insulin (-27%), GHb (-14%), and systolic (-7%) and diastolic blood pressure (-10%) levels and the glucose response area (-17%) independent of diet composition. Diet composition did affect the lipoprotein profile. LDL was 10% and 17% lower with the high-carbohydrate and high-MUFA diets, respectively, whereas no change was observed with the high-SFA diet (P < 0.001 for effect of diet). HDL was transiently reduced on the high-carbohydrate diet at weeks 1, 4, and 8, whereas higher fat consumption maintained these levels. The total cholesterol:HDL ratio, although significantly reduced on the high-MUFA diet (P < 0.01), was not different from the other two diets after adjustment for baseline differences. CONCLUSIONS: Energy restriction, independent of diet composition, improves glycemic control; however, reducing SFA intake by replacing SFA with carbohydrate or MUFA reduces LDL maximally during weight loss and to a greater degree than has been shown in weight-stable studies.

Effects of energy-restricted diets containing increased protein on weight loss, resting energy expenditure, and the thermic effect of feeding in type 2 diabetes.

OBJECTIVE: To determine the effect of a high-protein (HP) diet compared with a low-protein (LP) diet on weight loss, resting energy expenditure (REE), and the thermic effect of food (TEF) in subjects with type 2 diabetes during moderate energy restriction. RESEARCH DESIGN AND METHODS: In this study, 26 obese subjects with type 2 diabetes consumed a HP (28% protein, 42% carbohydrate) or LP diet (16% protein, 55% carbohydrate) during 8 weeks of energy restriction (1,600 kcal/day) and 4 weeks of energy balance. Body weight and composition and REE were measured, and the TEF in response to a HP or LP meal was determined for 2 h, at weeks 0 and 12. RESULTS: The mean weight loss was 4.6 +/- 0.4 kg (P < 0.001), of which 4.5 +/- 0.4 kg was fat (P < 0.001), with no effect of diet (P = 0.6). At both weeks 0 and 12, TEF was greater after the HP than after the LP meal (0.064 vs. 0.050 kcal x kcal(-1) energy consumed x 2 h(-1), respectively; overall diet effect, P = 0.003). REE and TEF were reduced similarly with each of the diets (time effects, P = 0.02 and P < 0.001, respectively). CONCLUSIONS: In patients with type 2 diabetes, a low-fat diet with an increased protein-to-carbohydrate ratio does not significantly increase weight loss or blunt the fall in REE.

Steroidal contraceptive use is associated with lower bone mineral density in polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is a common condition affecting reproductive-aged women with features including hyperandrogenism and menstrual irregularity frequently treated with hormonal steroidal contraceptives. Women with PCOS appear to have lower bone mineral density (BMD). While steroidal contraceptives may positively affect bone health, their effect on BMD in PCOS is not known. The aim of this study was to assess BMD in women with PCOS according to recent contraceptive use. A cross-sectional analysis of 95 pre-menopausal overweight or obese sedentary women with PCOS [age 29.4 ± 6.4 years, body mass index (BMI) 36.1 ± 5.3 kg/m(2)] who either recently took steroidal contraceptives (ceased 3 months prior) or were not taking steroidal contraceptives was conducted. Clinical outcomes included BMD, anthropometry, insulin, glucose, reproductive hormones, dietary intake and vitamin use. BMD was significantly lower for women who used contraceptives compared to those who did not (mean difference 0.06 g/cm(2) 95 % confidence interval -0.11, -0.02, p = 0.005). In regression models, lower BMD was independently associated with contraceptive use (ß = -0.05, 95 % CI -0.094, -0.002, p = 0.042), higher testosterone (ß = -0.03, 95 % CI -0.05, -0.0008, p = 0.043) and lower BMI (ß = 0.006, 95 % CI 0.002, 0.01, p = 0.007) (r (2) = 0.22, p = 0.001 for entire model). We report for the first time that overweight and obese women with PCOS with recent steroidal contraceptive use had lower BMD in comparison to non-users independent of factors known to contribute to BMD. Whether this observation is directly related to steroidal contraceptive use or other factors requires further investigation.

Dietary composition in restoring reproductive and metabolic physiology in overweight women with polycystic ovary syndrome.

Overweight women with polycystic ovary syndrome (PCOS) were randomized to a high protein (HP; 40% carbohydrate and 30% protein; n = 14) or a low protein (LP; 55% carbohydrate and 15% protein) diet (n = 14). The intervention consisted of 12 wk of energy restriction (approximately 6000 kJ/d), followed by 4 wk of weight maintenance. Pregnancies (two HP and one LP); improvements in menstrual cyclicity, lipid profile, and insulin resistance (as measured by the homeostasis model); and decreases in weight (7.5%) and abdominal fat (12.5%) occurred independently of diet composition. Improvements in menstrual cyclicity were associated with greater decreases in insulin resistance and fasting insulin (P = 0.011). On the LP diet, high density lipoprotein cholesterol decreased 10% during energy restriction (P = 0.008), and the free androgen index increased 44% in weight maintenance stages (P = 0.027). Weight loss leads to improvements in cardiovascular and reproductive parameters potentially mediated by improvements in surrogate measures of insulin resistance. An HP weight loss diet may result in minor differential endocrine and metabolic improvements.

Ghrelin and measures of satiety are altered in polycystic ovary syndrome but not differentially affected by diet composition.

Polycystic ovary syndrome (PCOS) is a common endocrine condition in women of reproductive age associated with obesity. It may involve dysregulation of ghrelin, a hormone implicated in appetite regulation. The effect of diet composition on ghrelin is unclear. Overweight women with and without PCOS were randomized to a high-protein (40% carbohydrate, 30% protein; 10 PCOS, six non-PCOS) or standard protein diet (55% carbohydrate, 15% protein; 10 PCOS, six non-PCOS) for 12 wk of energy restriction and 4 wk of weight maintenance. Diet composition had no effect on fasting or postprandial ghrelin or measures of satiety. Non-PCOS subjects had a 70% higher fasting baseline ghrelin (P = 0.011), greater increase in fasting ghrelin (57.5 vs. 34.0%, P = 0.033), and greater maximal decrease in postprandial ghrelin after weight loss (-144.1 +/- 58.4 vs. -28.9 +/- 14.2 pg/ml, P = 0.02) than subjects with PCOS. Subjects with PCOS were less satiated (P = 0.001) and more hungry (P = 0.007) after a test meal at wk 0 and 16 than subjects without PCOS. Appetite regulation, as measured by subjective short-term hunger and satiety and ghrelin homeostasis, may be impaired in PCOS.