With nearly 16 million Americans living today with prediabetes, a condition that is the precursor to type 2 diabetes, and half of all Americans expected to have either prediabetes or type 2 diabetes by the year 2020, nutritional approaches to maintaining healthy blood sugar levels are essential.1,2 The findings of a scientific study examining the health promotion and disease prevention benefits of almond consumption were published in the June, 2010 Journal of the American College of Nutrition. The study, one of the first of its kind to quantify prevention data, illustrates that consuming an almond-enriched diet may help improve insulin sensitivity and decrease LDL-cholesterol levels in those with prediabetes.3,4
The study looked at the effects of consuming an almond-enriched diet on factors linked to the progression of type 2 diabetes and cardiovascular disease in adults with prediabetes. After 16 weeks of consuming either an almond-enriched or regular diet, both in accordance with American Diabetes Association (ADA) recommendations, the group that consumed an almond-enriched diet showed significantly improved LDL-cholesterol levels and measures of insulin sensitivity, risk factors for heart disease and type 2 diabetes. A caveat is that although study participants in both groups were instructed to consume the same amount of calories from carbohydrates, there was less self-reported carbohydrate intake among those in the almond group.4
“We have made great strides in chronic disease research from evidence of effective treatment to evidence of effective prevention” said Dr. Michelle Wien, Assistant Research Professor in Nutrition at Loma Linda University’s School of Public Health and Principal Investigator for this study, which was conducted at the University of Medicine and Dentistry of New Jersey. Wien adds, “It is promising for those with risk factors for chronic diseases, such as type 2 diabetes and cardiovascular disease, that dietary changes may help to improve factors that play a potential role in the disease development. It would be beneficial to conduct tightly controlled metabolic feeding studies and postprandial studies that feature controlled amounts of carbohydrate to confirm the findings of this study, which was performed in a free-living population.”
Study at a Glance:
- The People: 65 adults with prediabetes (48 women and 17 men) with an average age of 53.5 +10y.4
- The Diet: The study population was randomly divided into either the intervention or control group. The control group consumed a diet that conformed with the American Diabetes Association (ADA) recommendations, which consists of 15-20% calories from protein, 10% total energy from saturated fat, 60-70% from carbohydrate and monounsaturated fatty acids (MUFA) and cholesterol < 300mg/day for 16 weeks, excluding all nuts. The intervention group consumed the ADA-recommended diet with 20% of the calories from almonds.4
- The Results: The intervention group, who were on an almond-enriched diet, showed greater improvements in insulin levels (-1.7µU/ml vs. +1.47µU/ml, p=0.002), homeostasis model analysis for insulin resistance (-0.48 vs. +0.30, p=0.007), homeostasis model analysis for beta-cell function (-13.2 vs. +22.3, p=0.001) and clinically significant reductions in LDL-cholesterol (-12.4 mg/dl vs. -0.4 mg/dl) as compared to the nut-free group.4
This study suggests that consuming an ADA-recommended diet consisting of 20% of the total calories from almonds for 16 weeks is effective in improving LDL cholesterol levels and measures of insulin sensitivity in individuals with prediabetes.4 Nutrients in almonds, such as fiber and unsaturated fat, have been shown to help reduce LDL-cholesterol levels, increase insulin sensitivity and increase beta-cell function, all of which can help to prevent the development of type 2 diabetes and reduce the risk of cardiovascular disease.
This study contributes to the growing body of evidence that suggests that almonds contribute to heart health. However, this study adds a new dimension to the existing research as it shows that almond consumption not only aids in disease management, but may contribute to risk reduction for certain chronic diseases through their nutrient composition. Almonds offer 3.5 grams of fiber, 13 grams of unsaturated fat and only 1 gram of saturated fat per one-ounce serving.5
1 Cowie CC, et al. Full accounting of diabetes and pre-diabetes in the U.S. population in 1988-1994 and 2005-2006. Diabetes Care 32 : 287-294, 2009.
2 United Health Center for Health Reform and Modernization. The United States of Diabetes : Challeneges and Opportunities in the Decade Ahead. November 2010.
3 Scientific evidence suggests, but does not prove, that eating 1.5 ounces per day of most nuts, such as almonds, as part of a diet low in saturated fat and cholesterol may reduce the risk of heart disease.
4 Wien M, et al. Almond consumption and cardiovascular risk factors in adults with prediabetes. J Am Coll Nutr. 2010 Jun;29(3):189-97.
5 U.S. Department of Agriculture, Agricultural Research Service, 2010. USDA National Nutrient Database for Standard Reference, Release 23.
Source: Porter Novelli