OBJECTIVE -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.RESEARCH DESIGN AND METHODS -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 Ϯ 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, HbA 1c , 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. RESULTS -The walnut group achieved a significantly greater increase in HDL cholesterolto-total cholesterol ratio (P ϭ 0.049) and HDL (P ϭ 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 ϭ 0.032) and time (P ϭ 0.036). There were no significant differences between groups for changes in body weight, percent body fat, total antioxidant capacity, or HbA 1c levels. The higher dietary polyunsaturated fat-to-saturated fat ratio and intakes of -3 fatty acids in the walnut group were confirmed by erythrocyte biomarkers of dietary intake.CONCLUSIONS -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. The literature on recommendations varies to a minor degree, and cultural differences may have an influence (9), but a total fat level of Յ30% energy (10) and Ͻ10% saturated fat is reasonably well accepted (11,12). There is some concern that PUFAs are more susceptible to oxidation and therefore may be more atherogenic (11), so a level of Ͻ10% energy for PUFAs is seen with greater flexibility in the proportions of carbohydrate and MUFA (13). Within the PUFA fraction of the diet, the ratio of -6 to -3 fatty acids is also considered (9) with daily recommendations for a 2,000-kcal diet of 0.65 g for the long-chain -3s (EPA ϩ DHA) and 2.22 g for ALA (14) and the -6 -to--3 ratio reduced to substantially Ͻ10 (14a). Diabetes CareFish are the major source of EPA ϩ DHA, but fish oil supplements produce a decreased oxidative stability of plasma LDL (15,16). In contrast, consumption of fish itself may be protective against type 2 diabetes (17). Nuts provide substantial amounts of dietary PUFA, and nut consumption is inversely associated with the risk of type 2 diabetes in women (18). There is no net effect on glucose homeostasis from nut supplementation, but more interestingly, no net weight gain when nuts were used as a replacement food (19). In subjects with dyslipidemia (total cholesterol Ͼ5.17; LDL Ͼ3.36; triglycerides Ͼ2.26 mmol/l), a low-fat diet supplemented with walnuts was found to reduce total choles...

Background/Objectives: Most dietary interventions have metabolic effects in the short term, but long-term effects may require dietary fat changes to influence body composition and insulin action. This study assessed the effect of sustained high polyunsaturated fatty acids (PUFA) intake through walnut consumption on metabolic outcomes in type II diabetes. Subjects/Methods: Fifty overweight adults with non-insulin-treated diabetes (mean age 54±8.7 years) were randomized to receive low-fat dietary advice ± 30 g per day walnuts targeting weight maintenance (around 2000 kcal, 30% fat) for 1 year. Differences between groups were assessed by changes in anthropometric values (body weight, body fat, visceral adipose tissue) and clinical indicators of diabetes over treatment time using the general linear model. Results: The walnut group consumed significantly more PUFA than the control (P ¼ 0.035), an outcome attributed to walnut consumption (contributing 67% dietary PUFA at 12 months). Most of the effects were seen in the first 3 months. Despite being on weight maintenance diets, both groups sustained a 1-2 kg weight loss, with no difference between groups (P ¼ 0.680). Both groups showed improvements in all clinical parameters with significant time effects (Po0.004), bar triacylglycerol levels, but these were just above normal to begin with. The walnut group produced significantly greater reductions in fasting insulin levels (P ¼ 0.046), an effect seen largely in the first 3 months. Conclusions: Dietary fat can be manipulated with whole foods such as walnuts, producing reductions in fasting insulin levels. Long-term effects are also apparent but subject to fluctuations in dietary intake if not of the disease process.

The inflammatory bowel diseases (IBDs) are a group of heterogeneous disorders characterized by acute and chronic inflammatory changes in the small or large bowel, or in both. Increasing incidence and prevalence figures for IBD both in the developed and developing world indicate that environmental factors are at least as significant in IBD as genetic susceptibility. Of these, diet and the host microbiota are likely to play important but as yet poorly defined roles. The major constituents of a standard "Western" diet may contribute to, or protect against, intestinal inflammation via several mechanisms. These include the effects of insulin resistance and short-chain fatty acids such as butyrate, modification of intestinal permeability, the antiinflammatory role of polyunsaturated fatty acids, and the effect of sulfur compounds from protein on host microbiota. This detailed review critically assesses the evidence for the role of diet in the development of IBD and examines the evidence for obesity as a contributing factor to IBD pathogenesis. Particular attention is focused on methodological issues including suitability of cases and controls, confounders such as smoking, and total energy expenditure.

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Foods commonly consumed by 16 adults with diabetes were grouped according to macrinutrient value and type of fat to form 13 categories of which 10 would form the focus of dietary advice. Dietary modeling demonstrated that the food group pattern provided adequate nutrition and low variation in dietary targets. Idealised proportions of fat types were achieved only when daily servings of foods such as oils, nuts, oily fish and soy were included. The food groupings proved appropriate for dietary advice for diabetes.