Like all nuts, walnuts contain monounsaturated and polyunsaturated fats (PUFAs), but they are also a good source of the essential omega-3 fatty acids. They also contain iron, selenium, calcium, zinc, vitamin E and vitamin B, which help the body maintain an optimum nutritional level.
The Yale University School of Medicine Care explored the effects of walnut consumption on blood vessels for Type 2 diabetics in one of their studies. "Patients followed a diet with or without 56 grams of walnuts for eight weeks, and scientists found that the walnut group experienced improvements in the function of blood vessel lining compared to the non-walnut group," the report read.
Not only does it affect the blood vessels, but also fastens the insulin levels in Type 2 diabetics. The report from the European Journal of Clinical Nutrition said, "If a patient consumes 30 grams of walnuts for one year, it can bring significant reduction in their fasting insulin levels as compared to the patients who are not consuming walnuts."
As walnuts are a rich source of alpha-linolenic acid - a healthy omega-3 fatty acid - it might improve diabetic neuropathy, which is a complication of diabetes that results in damaged nerves.