Effectiveness of intermittent fasting for weight loss in individuals with obesity: A meta-analysis of randomized controlled trials.

AIM: To assess whether intermittent fasting (IF) diets are associated with improvement in weight loss, metabolic parameters, and subjective well-being, in people with obesity. DATA SYNTHESIS: We performed a Meta-analysis of Randomized Controlled Trials longer than 2 months, retrieved through an extensive search on MedLine, Cochrane CENTRAL Library, and Embase online databases, comparing weight loss with IF diets and control diets in people with Body Mass index (BMI) > 30 kg/m2. We retrieved 9 trials, enrolling 540 patients. IF was not associated with a significantly greater reduction of body weight or BMI at any time point with respect to controls or in respect to continuous restricted diets, with low-to moderate quality of evidence; no significant difference in efficacy between alternate day fasting and time restricted eating was found. Differences in fasting plasma glucose, total or high-density lipoprotein cholesterol or blood pressure at any time point were not statistically significant, whereas a reduction of low-density lipoprotein cholesterol (MD -8.39 [-15.96, -0.81] mg/dl, P = 0.03; I2 = 0%) was observed at 2-4 months, but not in the longer term. Data on psychological parameters and overall well-being were insufficient to perform a formal meta-analysis, whereas a qualitative synthesis did not show any difference between IF and controls. CONCLUSIONS: IF is not associated with greater or lesser weight loss than non-intermittent fasting diets. Further data on psychological parameters and overall well-being are needed to properly assess the role of IF diets in the management of obesity.

Effectiveness of low-carbohydrate diets for long-term weight loss in obese individuals: A meta-analysis of randomized controlled trials.

AIM: To assess whether low-carbohydrate (LC) diets are associated with differences in weight loss and well-being in people with obesity, and their cardiovascular and renal safety. MATERIALS AND METHODS: A meta-analysis of randomized controlled trials longer than 3 months, retrieved through an extensive search on MedLine and Embase databases, comparing weight loss with LC and control diets in people with body mass index (BMI) greater than 30 kg/m2 , was conducted. RESULTS: We retrieved 25 trials. Compared with controls, LC diets were associated with significant reduction of body weight at 3-4 (MD -2.59 [-3.93, -1.25] kg) and 6-8 months (MD -2.64 [-4.32, -0.95]), but no difference at 10-14 and 18-30 months, and significantly greater BMI reduction at 3-4 months (-1.66 [-2.70, -0.61] kg/m2 ), but not at other time points. Because only four trials reported data on renal function and psychological variables, renal safety and impact on well-being could not be assessed. Differences in fasting plasma glucose at any time point were not statistically significant. No significant differences in total or LDL cholesterol or blood pressure were found in the long term, whereas a long-term reduction of triglycerides (23.26 [-45.53, -0.98] mg/dl at 18-30 months), and increase of HDL cholesterol (MD 4.94 [0.30, 9.57] mg/dl at 18-30 months), were observed. CONCLUSION: LC diets are associated with greater short-term weight loss than non-carbohydrate-restricted diets and a longer term favourable effect on cardiovascular risk factors. Further evidence on long-term efficacy and renal safety is needed before LC diets can be recommended as the preferred diets in obese people.

Anthropometric and dietary determinants of blood pressure in over 7000 Mediterranean women: the European Prospective Investigation into Cancer and Nutrition-Florence cohort.

BACKGROUND: Anthropometric characteristics and dietary habits are widely recognized to influence blood pressure. We evaluated their role in a large series of Mediterranean adult women. METHODS: In Florence, in the European Prospective Investigation into Cancer and Nutrition, we recruited 10 083 women, aged 35-64 years. Detailed information on diet, lifestyle, physical activity, and medical history were collected. Anthropometric indices and systolic and diastolic blood pressures were measured at recruitment using standardized procedures. Overall, after excluding those women who reported a clinical diagnosis of hypertension and/or an antihypertensive treatment and those without measurements, 7601 women were available for analyses with an average systolic and diastolic blood pressure value of 123.2+/-16.0 and 78.7+/-9.4 mmHg, respectively. RESULTS: Multivariate regression models showed that body mass index (P<0.0001) and waist circumference (>or=88 cm, P<0.0001), as well as processed meat, potatoes, and wine consumption, were directly associated with both systolic and diastolic values. In contrast, a high consumption of selected foods resulted inversely associated with systolic (total vegetables, yoghurt, and eggs), diastolic (olive oil) or both systolic and diastolic values (leafy vegetables, milk, coffee). Analyses performed on nutrients showed a positive association with alcohol and sodium intake, and an inverse one with potassium and micronutrients derived from fruits and vegetables. CONCLUSION: In this large series of women from Tuscany, Central Italy, we confirm the independent influence of anthropometric characteristics on blood pressure. The role of specific foods and nutrients in modulating blood pressure also emerged, suggesting a central role for lifestyle modifications in blood pressure control.