Including walnuts in a low-fat/modified-fat diet improves HDL cholesterol-to-total cholesterol ratios in patients with type 2 diabetes

National Centre of Excellence in Functional Foods, Northfields Avenue, University of Wollongong, NSW 2522, Australia.
Diabetes Care (Impact Factor: 8.57). 01/2005; 27(12):2777-83. DOI: 10.2337/diacare.27.12.2777
Source: PubMed

ABSTRACT The aim of this study was to examine the effect of a moderate-fat diet inclusive of walnuts on blood lipid profiles in patients with type 2 diabetes.
This was a parallel randomized controlled trial comparing three dietary advice groups each with 30% energy as fat: low fat, modified low fat, and modified low fat inclusive of 30 g of walnuts per day. Fifty-eight men and women, mean age 59.3 +/- 8.1 years, started the trial. Dietary advice was given at baseline with monthly follow-up and fortnightly phone calls for support. Body weight, percent body fat, blood lipids, HbA1c, total antioxidant capacity, and erythrocyte fatty acid levels were measured at 0, 3, and 6 months. Data were assessed by repeated-measures ANOVA with an intention-to-treat model.
The walnut group achieved a significantly greater increase in HDL cholesterol-to-total cholesterol ratio (P=0.049) and HDL (P=0.046) than the two other treatment groups. A 10% reduction in LDL cholesterol was also achieved in the walnut group, reflecting a significant effect by group (P=0.032) and time (P=0.036). There were no significant differences between groups for changes in body weight, percent body fat, total antioxidant capacity, or HbA1c levels. The higher dietary polyunsaturated fat-to-saturated fat ratio and intakes of omega-3 fatty acids in the walnut group were confirmed by erythrocyte biomarkers of dietary intake.
Structured "whole of diet" advice that included 30 g of walnuts/day delivering substantial amounts of polyunsaturated fatty acid improved the lipid profile of patients with type 2 diabetes.

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Available from: Lynda J Ross, Dec 17, 2013
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    • "Hence, the inclusion of walnuts in a healthy diet can decrease serum cholesterol concentrations [85]. Fifty-eight subjects were randomized into three treatment arms of different dietary advice: a conventional low-fat control diet, a low-but modified-fat diet higher in eicosapentaenoic and docosahexaenoic acids and PUFAs, and a low-fat plus a diet of walnuts 30 g/d high in a-linolenic acid [44]. The results indicated that body fat did not change during the walnut (30 g/d) intervention period of 6 mo compared with the baseline level (Fig. 5). "
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