Nuts: an important component of an anti-diabetes diet
Complications from diabetes result from constant elevations in blood glucose, which damage the blood vessels and other tissues. Excess glucose in the bloodstream results in the formation of Advanced Glycation End Products (AGEs) – products formed when sugars react with and consequently damage proteins or fats in the body’s tissues, especially the blood vessels. AGEs are produced at an accelerated rate in diabetics and contribute to complications such as impaired wound healing, diabetic nephropathy, and atherosclerosis.1-4 In addition to the AGE produced in the body due to excess glucose, some can also come from the diet. Fried foods, meats, and dry cooked starchy foods (roasted/fried potatoes, bread, crackers, cookies, muffins and other baked goods, cold cereals, etc.) are high in AGEs.5,6
Lessening after-meal blood glucose and exposure to AGEs:
In designing a diet for type 2 diabetics, we aim to limit after-meal increases in blood glucose and to avoid dangerous AGEs by choosing major calorie sources with a low glycemic load (GL) – foods that provoke relatively small increases in blood glucose. An important point here is to choose high nutrient, low GL foods, not just any low GL food – this is where some conventional diabetes diets fall short:
- Meat is a low GL food, but higher meat consumption is associated with reduced lifespan and increased risk of developing type 2 diabetes; the diabetes risk is likely due to weight gain and AGE content.5,7,8 A diabetic diet emphasizing meat sacrifices long-term health for short-term glycemic control.
- Whole grain products and starchy vegetables. Whole grain intake is indeed associated with reduced risk of diabetes, probably due to fiber content.9,10 A low fat vegan diet emphasizing these foods in place of refined carbohydrates has shown some success with improving glycemic control.11 However, these diets tend to increase triglyceride levels (a risk factor for heart disease)12, and cooked grains and starches are not ideal calorie sources for diabetics because they still have a significant GL, as you can see in the table below:
|Whole grain (brown rice)||18|
|Beans (black or kidney)||7|
Beans, and nuts (and seeds) are high in nutrients and low in GL, and are far more appropriate than grains and meat as major calorie sources for diabetics.
Beans and legumes are higher in fiber and resistant starch than whole grains, with a lower GL. (To read more about why beans are superior to other carbohydrate sources for diabetics, read my recent Healthy Times Newsletter, Issue #44)
Regular consumption of nuts and seeds has well documented cardiovascular benefits, including cholesterol lowering, antioxidant activity, improved endothelial function, and reduced risk of sudden cardiac death and coronary heart disease.14
In addition to reducing the risk of cardiovascular disease, nuts have a number of properties that make them a favorable food for diabetics:15
Nuts are a high-nutrient source of plant protein, fiber, antioxidants, phytosterols, and minerals.
Nuts provoke a minimal glycemic response, which helps to prevent post-meal hyperglycemia, hyperinsulinemia, and AGE production. They also help to reduce the GL of an entire meal – almonds have been found to decrease glycemic and insulin response of a carbohydrate-rich meal while reducing oxidative stress.16
Nuts aid in weight maintenance – important since excess weight is the primary risk factor for diabetes. Despite their calorie density, greater nut consumption is associated with lower body weight, potentially due to appetite-suppression from healthy fats.17
Nuts have anti-inflammatory effects that may help to prevent insulin resistance18
In a study, HbA1C, an indicator of long term glycemic control, was measured in diabetics consuming either 2.5 ounces/day of mostly raw mixed nuts or an equivalent number of calories in a muffin – a cooked starchy food (the muffin had the same amount of fiber and calories as the nuts). HbA1C levels were lower in the nut group, suggesting long term protection from hyperglycemia when replacing carbohydrate foods with nuts.19,20
This data cements the results of previous observational studies that have found inverse relationships between nut consumption and diabetes. For example, the Nurses’ Health Study found a 27% reduced risk of diabetes in nurses who ate five or more servings of nuts per week. Among nurses who already had diabetes, this same quantity reduced the risk of heart disease by 47%.21-23
Nuts are an important part of a diabetes-reversal diet, along with green vegetables24, beans25, and low sugar fruits. In a study on type 2 diabetics following this diet, we found that 62% of the participants reached normal (nondiabetic) HbA1C levels within seven months, and the average number of medications required dropped from four to one.26 Nuts, seeds, beans, and vegetables not only keep glucose levels in check, but promote long term health as well.
1. Peppa M, Raptis SA: Glycoxidation and Wound Healing in Diabetes: An Interesting Relationshi. Curr Diabetes Rev 2011.
2. Peppa M, Stavroulakis P, Raptis SA: Advanced glycoxidation products and impaired diabetic wound healing. Wound Repair Regen 2009;17:461-472.
3. Goldin A, Beckman JA, Schmidt AM, et al: Advanced glycation end products: sparking the development of diabetic vascular injury. Circulation 2006;114:597-605.
4. Yamagishi S, Matsui T: Advanced glycation end products, oxidative stress and diabetic nephropathy. Oxid Med Cell Longev 2010;3:101-108.
5. Goldberg T, Cai W, Peppa M, et al: Advanced glycoxidation end products in commonly consumed foods. J Am Diet Assoc 2004;104:1287-1291.
6. Pruser KN, Flynn NE: Acrylamide in health and disease. Front Biosci (Schol Ed) 2011;3:41-51.
7. Sinha R, Cross AJ, Graubard BI, et al: Meat intake and mortality: a prospective study of over half a million people. Arch Intern Med 2009;169:562-571.
8. Aune D, Ursin G, Veierod MB: Meat consumption and the risk of type 2 diabetes: a systematic review and meta-analysis of cohort studies. Diabetologia 2009;52:2277-2287.
9. Montonen J, Knekt P, Jarvinen R, et al: Whole-grain and fiber intake and the incidence of type 2 diabetes. Am J Clin Nutr 2003;77:622-629.
10. Fung TT, Hu FB, Pereira MA, et al: Whole-grain intake and the risk of type 2 diabetes: a prospective study in men. Am J Clin Nutr 2002;76:535-540.
11. Trapp CB, Barnard ND: Usefulness of vegetarian and vegan diets for treating type 2 diabetes. Curr Diab Rep 2010;10:152-158.
12. Lichtenstein AH, Van Horn L: Very low fat diets. Circulation 1998;98:935-939.
13. Foster-Powell K, Holt SH, Brand-Miller JC: International table of glycemic index and glycemic load values: 2002. Am J Clin Nutr 2002;76:5-56.
14. Kris-Etherton PM, Hu FB, Ros E, et al: The role of tree nuts and peanuts in the prevention of coronary heart disease: multiple potential mechanisms. J Nutr 2008;138:1746S-1751S.
15. Kendall CW, Josse AR, Esfahani A, et al: Nuts, metabolic syndrome and diabetes. Br J Nutr 2010;104:465-473.
16. Jenkins DJ, Kendall CW, Josse AR, et al: Almonds decrease postprandial glycemia, insulinemia, and oxidative damage in healthy individuals. J Nutr 2006;136:2987-2992.
17. Martinez-Gonzalez MA, Bes-Rastrollo M: Nut consumption, weight gain and obesity: Epidemiological evidence. Nutrition, metabolism, and cardiovascular diseases : NMCD 2011;21 Suppl 1:S40-45.
18. Casas-Agustench P, Bullo M, Salas-Salvado J: Nuts, inflammation and insulin resistance. Asia Pac J Clin Nutr 2010;19:124-130.
19. Jenkins DJ, Kendall CW, Banach MS, et al: Nuts as a replacement for carbohydrates in the diabetic diet. Diabetes Care 2011;34:1706-1711.
20. Barclay L: Replacing Carbs With Nuts May Be Beneficial in Diabetes. 2011. Medscape Education Clinical Briefs. http://www.medscape.org/viewarticle/746264. Accessed August 30, 2011.
21. Jiang R, Manson JE, Stampfer MJ, et al: Nut and peanut butter consumption and risk of type 2 diabetes in women. JAMA 2002;288:2554-2560.
22. Kendall CW, Esfahani A, Truan J, et al: Health benefits of nuts in prevention and management of diabetes. Asia Pac J Clin Nutr 2010;19:110-116.
23. Li TY, Brennan AM, Wedick NM, et al: Regular consumption of nuts is associated with a lower risk of cardiovascular disease in women with type 2 diabetes. J Nutr 2009;139:1333-1338.
24. Carter P, Gray LJ, Troughton J, et al: Fruit and vegetable intake and incidence of type 2 diabetes mellitus: systematic review and meta-analysis. BMJ 2010;341:c4229.
25. Villegas R, Gao YT, Yang G, et al: Legume and soy food intake and the incidence of type 2 diabetes in the Shanghai Women's Health Study. Am J Clin Nutr 2008;87:162-167.
26. Dunaief D, Gui-shuang Y, Fuhrman J, et al: Glycemic and cardiovascular parameters improved in type 2 diabetes with the high nutrient density diet. Presented at the 5th IANA (International Academy on Nutrition and Aging) meeting July 26 & 27, 2010 Hyatt Regency Tamaya Resort & Spa 1300 Tuyuna Trail Santa Ana Pueblo, NM, USA J Nutr Health Aging 2010;14:500.