Peanuts can often be found on coffee tables, at baseball games, tossed in salads, stir fried with vegetables and topped on sundaes. There is now emerging evidence that peanuts, which play an integral role in our culture, may benefit vascular health.
While “nut” is in their name, peanuts are in fact legumes. Peanuts grow underground, as opposed to nuts such as walnuts and almonds, which grow on trees.
Legumes are edible seeds enclosed in pods. As a group, they provide one of the best sources of concentrated protein in the plant kingdom. While the physical structure and nutritional benefits of peanuts more closely resemble that of other legumes, their use in diets and cuisines more closely resembles that of nuts.
A study of peanut consumption by the Department of Nutritional Sciences at The Pennsylvania State University shows that including peanuts as a part of a high-fat meal improved the post-meal triglyceride response and preserved endothelial function.
“Peanuts are a healthy snack when eaten as part of a healthy diet,” says lead researcher Xiaoran Liu, a graduate student at Penn State.
The research was conducted to evaluate vascular function after a high-fat meal challenge.
A group of 15 overweight males were randomized into one of two groups to consume one of two shakes:
- A peanut meal containing 3 oz of ground peanuts
- A control meal without peanuts.
Both of the shakes were high fat and matched for both energy and macronutrients.
After each meal the individuals had their lipid profile, glucose and insulin measured five times.
Vascular function was determined by measuring flow-mediated dilation (FMD). FMD is a noninvasive method of measuring vascular function through the use of a cuff worn on the forearm, which restrains blood flow. The cuff is then released to assess dilation of the brachial artery.
The results of the test revealed that the control meal decreased FMD by 1.2% compared to baseline. However, in contrast, there was no decrease in FMD after the peanut meal.
These findings highlight that the peanut meal maintained normal vascular function whereas the high fat-matched control meal impaired vascular function acutely.
Vascular dysfunction is a disorder of the vascular system characterized by poor function of the blood vessels. The condition plays a major role in the development of atherosclerosis and the formation of coronary plaques and lesions that lead to coronary artery disease.
Often following the consumption of a high-fat meal, a temporary reduction in vascular function occurs, until the fat that is in the blood from the meal has cleared.
Tactics to diminish this response to both dietary fat and its effect on vascular dysfunction may decrease the risk of coronary disease. The findings from the research suggest that peanut consumption might be the critical ingredient to decrease this risk and may protect against the formation of atherosclerosis as part of a high-fat meal.
“Previous studies have shown that individuals who consume peanuts more than two times a week have a lower risk of coronary heart disease. This study indicates that the protective effect of peanut consumption could be due, in part, to its beneficial effect on artery health.”
Liu notes that peanuts are energy dense, and people need to be aware of their calorie content when incorporating them into the diet. Peanuts must be a replacement for other food sources of calories within a meal rather than an addition. For example, peanuts can be substituted for high fat, nutrient-poor foods in the diet that contain solid fats.
Future work for Liu and colleagues will investigate the effects of peanut consumption on other risk factors, including inflammatory markers. Liu will present the research at the American Society for Nutrition’s Scientific Sessions & Annual Meeting during Experimental Biology 2015.
The Peanut Institute supported the study.
Medical News Today recently reported on a new study involving over 600 children that suggests if babies start eating peanut products regularly and frequently before the age of 11 months, there is a very good chance that those at a high risk of peanut allergy will not develop it.