Peanuts have a desirable fatty acid profile and are rich in vitamins, minerals and bioactive substances. Various studies have already shown that the consumption of peanuts or peanut oil reduces the risk of cardiovascular disease. In order to find out whether this effect is due to the monounsaturated and polyunsaturated fatty acids, or if the non-fat components of the peanut play a role in the risk reduction as well, US scientists investigated the effects of the consumption of peanuts, peanut oil and fat-free peanut flour in animal experiments. Since the metabolism of hamsters and humans is comparable, hamsters were selected for this study. A total of 76 hamsters received feed over 24 weeks, which promotes the development of arteriosclerosis due to the high fat and cholesterol content. The animals were divided into four feed groups. In one group, peanuts were added to the feed, in another, peanut oil was added, and the third group received the fat-free peanut flour. The fourth group did not have a peanut product (control group). All diets were made to have the same calorie content. Results: all hamsters that had eaten peanuts, peanut oil or peanut flour had lower LDL cholesterol levels (the so-called "bad" cholesterol), compared to the control group. The HDL cholesterol values, the "good" cholesterol, did not decrease from the feed. A high LDL cholesterol level is associated with the development of atherosclerosis, especially when the HDL cholesterol level is low. The effects were not only visible in the groups with peanuts and peanut oil but also in the peanut flour group. The scientists suspect that the reason for this is the high dietary fibre content in peanut flour, because high dietary fibre content can lower LDL cholesterol levels. Substances such as the amino acid arginine, folic acid and flavonoids belonging to the group of secondary crops are also found in peanut flour and contribute to heart health. Conclusion: The results indicate that in the animal experiment the consumption of peanuts, peanut oil and fat-free peanut flour delayed the development of arteriosclerosis. It is to be assumed that peanuts - as a regular part of the human diet - have equally positive effects maintaining of heart health.
Stephens AM et al.: Peanuts, Peanut Oil, and Fat Free Peanut Flour Reduced Cardiovascular Disease Risk Factors and the Development of Atherosclerosis in Syrian Golden Hamsters. Journal of Food Science. 2010;65(4):h116-122.