The effect of a low-fat, high-protein or high-carbohydrate ad libitum diet on weight loss maintenance and metabolic risk factors

Abstract

Background: High-protein (HP) diets are often advocated for weight reduction and weight loss maintenance. Objective: The aim was to compare the effect of low-fat, high-carbohydrate (HC) and low-fat, HP ad libitum diets on weight maintenance after weight loss induced by a very low-calorie diet, and on metabolic and cardiovascular risk factors in healthy obese subjects. Design: Forty-eight subjects completed the study that consisted of an energy restriction period of 5-6 weeks followed by a weight maintenance period of 12 weeks. During weight maintenance subjects received maltodextrin (HC group) or protein (HP group) (casein (HPC subgroup) or whey (HPW subgroup)) supplements (2 Â 25 g per day), respectively and consumed a low-fat diet. Results: Subjects in the HP diet group showed significantly better weight maintenance after weight loss (2.3 kg difference, P ¼ 0.04) and fat mass reduction (2.2 kg difference, P ¼ 0.02) than subjects in the HC group. Triglyceride (0.6 mM difference, P ¼ 0.01) and glucagon (9.6 pg ml À1 difference, P ¼ 0.02) concentrations increased more in the HC diet group, while glucose (0.3 mM difference, P ¼ 0.02) concentration increased more in the HP diet group. Changes in total cholesterol, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, insulin, HOMAir index, HbA1c, leptin and adiponectin concentrations did not differ between the diets. No differences were found between the casein-or whey-supplemented HP groups. Conclusions: These results show that low-fat, high-casein or whey protein weight maintenance diets are more effective for weight control than low-fat, HC diets and do not adversely affect metabolic and cardiovascular risk factors in weight-reduced moderately obese subjects without metabolic or cardiovascular complications.

Macronutrients and type 1 diabetes (revision number 6)

“…Four randomised controlled trials were identified that presented evidence on diets differing in the proportion of carbohydrate to protein on systolic and diastolic blood pressure, all of which were included in the meta-analysis (Appel et al, 2005;Leidy et al, 2007;Claessens et al, 2009;Delbridge et al, 2009). Three trials were subsequently identified in the update search (Aldrich et al, 2011;Gogebakan et al, 2011;Toscani et al, 2011) (Cardio-metabolic review, incident hypertension and blood pressure chapter p 51, 55 ; Update search table 48).…”

“…Six randomised controlled trials that presented evidence on diets differing in the proportion of carbohydrate to protein on fasting triacylglycerol concentration were included in the meta-analysis (Due et al, 2004;Appel et al, 2005;Noakes et al, 2005;Leidy et al, 2007;Claessens et al, 2009;Delbridge et al, 2009). Two trials were subsequently identified in the update search (Toscani et al, 2011;Gogebakan et al, 2011) Fasting total cholesterol 5.50.…”

“…Five randomised controlled trials that presented evidence on diets differing in the proportion of carbohydrate to fat on fasting LDL-cholesterol:HDL-cholesterol ratio were included in the meta-analysis (Turley et al, 1998;Zambon et al, 1999;Colette et al, 2003;Pelkman et al, 2004;Due et al, 2008b) 5.42. Six randomised controlled trials that presented evidence on diets differing in the proportion of carbohydrate to protein on fasting total cholesterol were included in the meta-analysis (Due et al, 2004;Appel et al, 2005;Noakes et al, 2005;Leidy et al, 2007;Claessens et al, 2009;Delbridge et al, 2009). Two trials were subsequently identified in the update search (Toscani et al, 2011;Gogebakan et al, 2011) (Appel et al, 2005), but the other four are weight loss trials.…”

“…less weight loss in one of the experimental groups  The effect is biologically relevant Fasting HDL-cholesterol 5.44. Five randomised controlled trials that presented evidence on diets differing in the proportion of carbohydrate to protein on fasting HDL-cholesterol concentration were included in the meta-analysis (Due et al, 2004;Appel et al, 2005;Noakes et al, 2005;Claessens et al, 2009;Delbridge et al, 2009). Two trials were subsequently identified in the update search (Toscani et al, 2011;Gogebakan et al, 2011) (Due et al, 2004;Appel et al, 2005;Noakes et al, 2005;Claessens et al, 2009;Delbridge et al, 2009).…”

Not All Calories in Foods are the same

“…If people increase their protein intake, they start losing weight without counting calories or controlling portions. Replacing carbohydrates with proteins can lead one on a fast track to weight loss [9,10].…”