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Walnuts and Health

Nutritious Food for People Living with Diabetes

Walnuts are a tasty and nutritious treat, but did you know that they are also a smart food choice for people living with diabetes? Research is finding that including the right types of fat in the diet, such as those found in walnuts, is particularly important to those with diabetes.

A Yale study published in Diabetes Care¹ finds walnuts improve blood flow in adults with type 2 diabetes.

Methods:

• Randomized, controlled, single-blind, cross-over trial included twenty-four adults (14 women, 10 men) with type 2 diabetes.
• Participants consumed 2 ounces of walnuts each day along with their normal diets during one 8-week period, and to simply follow their normal diets during another 8-week period.
• Endothelial function testing and cardiovascular biomarkers were assessed after each 8-week treatment phase.

Results:

• Endothelial function (a powerful predictor of cardiovascular risk) significantly improved after consumption of the walnut-enriched diet compared to the diet without walnuts.
• The researchers concluded that a walnut-enriched diet may improve endothelium-dependent vasodilatation in individuals with type 2 diabetes, thus reducing overall cardiac risk. It should be noted that not all of the individuals exhibited this improvement.
• Due to study limitations, future research is required in order to determine the specific role walnuts may have on endothelial function and blood lipids in individuals with type 2 diabetes.

A study published in the European Journal of Clinical Nutrition² found that walnuts, known for their high content of polyunsaturated fat (13g), significantly improve metabolic factors in overweight individuals with type 2 diabetes.

Methods:

• Fifty adults with non-insulin treated diabetes were randomized into followed either a healthy, low-fat control diet or a similar diet including an ounce of walnuts daily for a year.

Results:

• The walnut group consumed significantly more polyunsaturated fats than the control, an outcome attributed to walnut consumption.
• Both groups demonstrated a consistent weight loss during the first six months, however the control group experienced a consistent weight increase in the second six months, while the walnut group remained stable.
• The walnut group produced significantly greater reductions in fasting insulin levels, particularly in the first three months.

A study published in the December 2004 issue of Diabetes Care³ reported a positive effect of a moderate-fat diet, inclusive of walnuts, on blood lipid profiles in patients with type 2 diabetes.

Methods:

• A parallel randomized controlled trial included 58 men and women, ages 35-75, diagnosed with type 2 diabetes at least one year prior.
• Compared three dietary advice groups each with 30% energy as fat: 1) low fat, 2) modified low fat, and 3) modified low fat, inclusive of 30g walnuts (equivalent to around 8-10 nuts) per day.

Results:

• The walnut group achieved a 10% reduction in LDL cholesterol and a greater increase in HDL (good) cholesterol levels than the other two treatment groups.