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.


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.
Heilbronn
L K
LK
Department of Physiology, University of Adelaide, Australia. leonie.heilbronn@dhn.csiro.au
Noakes
M
M
Clifton
P M
PM
D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure; D015992:Body Mass Index; D002791:Cholesterol, Dietary; D003920:Diabetes Mellitus / Q000178:diet therapy* / Q000503:physiopathology; D003924:Diabetes Mellitus, Type 2 / Q000178:diet therapy* / Q000503:physiopathology; D003927:Diet, Diabetic; D004038:Diet, Reducing; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004043:Dietary Fiber; D004044:Dietary Proteins; D005260:Female; D006801:Humans; D008055:Lipids / Q000097:blood; D008074:Lipoproteins / Q000097:blood; D008297:Male; D008875:Middle Aged; D009765:Obesity; D015431:Weight Loss
D001786:Blood Glucose; D002791:Cholesterol, Dietary; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004043:Dietary Fiber; D004044:Dietary Proteins; D008055:Lipids; D008074:Lipoproteins