The study, published in Diabetes Care, reports that consuming two ounces of nuts daily as a replacement for carbohydrates may be an effective glycemic and serum lipid control for people with Type 2 diabetes.
“Mixed, unsalted, raw, or dry-roasted nuts have benefits for both blood glucose control and blood lipids and may be used as part of a strategy to improve diabetes control without weight gain,” said lead author Dr. David Jenkins, from the University of Toronto.
The researchers noted that fat intake, especially monounsaturated fatty acids (MUFA), have been shown to preserve HDL cholesterol and improve glycemic control, in diabetic patients, “yet the exact sources have not been clearly defined,” they said.
Many nuts, including cashews, walnuts, and almonds, are known to have higher levels of MUFAs, and have been touted as potentially having anti-diabetic effects.
Jenkins and his team therefore assessed the effect of mixed nut consumption on serum lipids and blood sugar control in type 2 diabetes.
Jenkins and his colleagues divided 117 patients with type 2 diabetes into three different groups. Each group was given a different supplementary meal for a period of three months: One group was given muffins, one was provided with a mixture of nuts including raw almonds, pistachios, walnuts, pecans, hazelnuts, peanuts, cashews, and macadamias, and one group was given a mixture of muffins and nuts.
People receiving the nut-only supplement reported the greatest improvement in blood glucose control, and were also found to have a reduction in low-density lipoprotein (LDL) cholesterol.
The authors noted that volunteers given muffins mixed muffin-and-nuts had no significant improvement in their blood sugar control, but did significantly lower their serum LDL levels.
People receiving the full dose of nuts reduced their HbA1c—a long-term marker of blood sugar control—by two-thirds of what the U.S. Food and Drug Administration recognizes as being clinically meaningful for therapeutic agents, said Jenkins.
“Furthermore, neither in the current study nor in previous reports has nut consumption been associated with weight gain. If anything, nuts appear to be well suited as part of weight-reducing diets,” said Jenkins.