Effect of a high-protein, high-monounsaturated fat weight loss diet on glycemic control and lipid levels in type 2 diabetes.
OBJECTIVE
To determine the effect of a high-protein (HP) weight loss diet compared with a lower-protein (LP) diet on fat and lean tissue and fasting and postprandial glucose and insulin concentrations.


METHODS
Replacing dietary protein for carbohydrate (CHO) during energy restriction and weight loss has been effective in sparing lean mass and improving insulin sensitivity in obese subjects but has not been tested in subjects with type 2 diabetes. We compared an HP diet (28% protein, 42% CHO, 28% fat [8% saturated fatty acids, 12% monounsaturated fatty acids, 5% polyunsaturated fatty acids]) with an LP diet (16% protein, 55% CHO, 26% fat [8% saturated fatty acids, 11% monounsaturated fatty acids, 5% polyunsaturated fatty acids]) in 54 obese men and women with type 2 diabetes during 8 weeks of energy restriction (1,600 kcal) and 4 weeks of energy balance. Body composition was determined by dual-energy X-ray absorptiometry at weeks 0 and 12.


RESULTS
Overall, weight loss of 5.2 +/- 1.8 kg was achieved independently of diet composition. However, women on the HP diet lost significantly more total (5.3 vs. 2.8 kg, P=0.009) and abdominal (1.3 vs. 0.7 kg, P=0.006) fat compared with the women on the LP diet, whereas, in men, there was no difference in fat loss between diets (3.9 vs. 5.1 kg). Total lean mass decreased in all subjects independently of diet composition. LDL cholesterol reduction was significantly greater on the HP diet (5.7%) than on the LP diet (2.7%) (P < 0.01).


CONCLUSIONS
Both dietary patterns resulted in improvements in the cardiovascular disease (CVD) risk profile as a consequence of weight loss. However, the greater reductions in total and abdominal fat mass in women and greater LDL cholesterol reduction observed in both sexes on the HP diet suggest that it is a valid diet choice for reducing CVD risk in type 2 diabetes.
Parker
Barbara
B
CSIRO Health Sciences and Nutrition, Adelaide, Australia.
Noakes
Manny
M
Luscombe
Natalie
N
Clifton
Peter
P
D015502:Absorptiometry, Photon; D000273:Adipose Tissue / Q000033:anatomy & histology; D001786:Blood Glucose / Q000187:drug effects / Q000378:metabolism*; D001823:Body Composition; D008078:Cholesterol, LDL / Q000097:blood; D003920:Diabetes Mellitus / Q000097:blood / Q000178:diet therapy* / Q000503:physiopathology; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000503:physiopathology*; D004042:Dietary Fats, Unsaturated / Q000494:pharmacology*; D004044:Dietary Proteins; D002149:Energy Intake; D004734:Energy Metabolism; D005229:Fatty Acids, Monounsaturated / Q000494:pharmacology*; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D007328:Insulin / Q000008:administration & dosage / Q000494:pharmacology; D008055:Lipids / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009765:Obesity; D015431:Weight Loss / Q000187:drug effects*
D001786:Blood Glucose; D008078:Cholesterol, LDL; D004042:Dietary Fats, Unsaturated; D004044:Dietary Proteins; D005229:Fatty Acids, Monounsaturated; D007328:Insulin; D008055:Lipids