A new study published in Nutrients shows that eating just 1.5 ounces of pecans – one small handful – every day may protect adults at risk for developing cardiovascular disease (CVD) and type 2 diabetes (T2D). Conducted by researchers at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, this study found that incorporating pecans into a typical American diet significantly improved insulin sensitivity and had a significant effect on markers of cardiometabolic disease in otherwise healthy overweight and obese adults with excess belly fat.
While a growing body of evidence has linked tree nuts such as pecans to reduced risk of CVD, this is the first study to look at the effects of pecan consumption on factors other than blood lipid levels and specifically those related to T2D. Obesity is a risk factor for T2D, and both obesity and T2D increase CVD risk.
"Pecans are naturally high in monounsaturated and polyunsaturated fats, so replacing a portion of the saturated fat in the diet with these healthier fats can explain some of the cardio-protective effects we observed," said lead researcher, Diane McKay, Ph.D. "But pecans also contain a number of bioactive plant compounds as well as vitamins and essential minerals that all likely contributed to this benefit. What's really interesting is that just one small change - eating a handful of pecans daily - may have a large impact on the health of these at-risk adults."
In this placebo-controlled crossover study of 26 men and women (average age 59 years), all meals were provided to carefully control their food intake. For four weeks at a time, subjects ate either a control diet with no nuts or the same diet with pecans substituted for 15% of the total calories. Both the control diet and the pecan-rich diet were low in fruits, vegetables and fibre. Calorie levels, as well as protein, carbohydrate, and total fat, were kept the same.
The study entitled "A Pecan-Rich Diet Improves Cardiometabolic Risk Factors in Overweight and Obese Adults: A Randomized Controlled Trial" is available online and will be presented at the American Society for Nutrition Annual Conference, Nutrition 2018 held in Boston this June. The study was funded by the National Pecan Shellers Association.