Written by Jessica Patella, ND. Research shows that people who eat nuts twice a week are 31% less likely to gain weight.
Nuts have been gaining favor as a healthy snack and for good reason. Research shows that people who eat nuts twice a week are 31% less likely to gain weight than those who don’t eat nuts (1). Consuming nuts has also been shown to have a positive effect on cholesterol levels and decreases risk factors for cardiovascular disease (2-4). Total nut consumption in the US is estimated at 12.9 g per day, with peanuts making up 65% of the consumption (peanuts make up 45% in the EU).
A recent study identified which nuts are highest in antioxidants and which have the most effect on the body (2). Nine different nuts were studied: walnuts, pistachios, pecans, peanuts, macadamias, hazelnuts, cashews, Brazil nuts and almonds. Two forms of peanut butter (crunchy & creamy) (2) were also studied.
The nuts were tested for levels of polyphenols, an antioxidant that protects against aging and oxidation in the body. For example, when LDL cholesterol is oxidized in the body it can become “glued” to artery walls and can cause heart disease. This is one of the reasons nuts have been shown to improve heart disease; the polyphenols can bind to LDL cholesterol so they don’t become “glued” to the artery walls (2).
After testing, walnuts had the highest levels of polyphenols in both raw and roasted nuts. The order of total polyphenols in raw nuts, starting with the highest is: walnut > Brazil nut > pistachio ~ pecan ~ peanut ~ almond > macademia > cashew ~ hazelnut*. The order of total polyphenols in roasted nuts, starting with the highest is: walnut > Brazil nut > hazelnut > peanut ~ pecan ~ cashew > macademia ~ almond > pistachio.
When determining how effective the antioxidants were, roasting did cause a 37% decline in efficacy (p=0.14). However, nuts’ antioxidant efficacy (measured as plasma LDL oxidation) still averaged 3 times better than alpha-tocopherol (vitamin E), ranging from 15 times for raw walnuts and 1.9 times for roasted cashews (2).
Polyphenols are also found in fruits and vegetables, but the US per capita consumption of fruits has declined 6% and consumption of vegetables has declined 13% since the 1990s (2). Therefore, nuts provide a major source of antioxidants in the US (2).
In conclusion, nuts provide beneficial nutrients and antioxidants for the body, which offer significant health benefits to the consumer (2).
* The symbol ~ indicates that the levels were about the same
>indicates greater than
Source: Vinson, Joe A., and Yuxing Cai. “Nuts, especially walnuts, have both antioxidant quantity and efficacy and exhibit significant potential health benefits.” Food & function 3.2 (2012): 134-140.
Open Access Article. Published on 21 December 2011. Downloaded on 18/05/2017 18:00:22.
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Posted June 21, 2012.
Jessica Patella, ND, is a naturopathic physician specializing in nutrition and homeopathic medicine and offers a holistic approach to health.
References:
- M. Bes-Rastrollo, et al. Prospective study of nut consumption, long-term weight change, and obesity risk in women, Am. J. Clin. Nutr., 2009, 89, 1913–1919.
- Vinson J, Yuxing C. Nuts, especially walnuts, have both antioxidant quality and efficacy and exhibit significant potential health benefits. The Royal Soc of Chem. 2011. doi:10.1039/C2FO10152A.
- D. J. A. Jenkins, et al. Dose response of almonds on coronary heart disease risk factors: blood lipids, oxidized low-density lipoproteins, lipoprotein(a), homocysteine, and pulmonary nitric oxide: a randomized, controlled, crossover trial, Circulation, 2002, 106, 1327–1332.
- S. K. Gebauer, et al. Effects of pistachios on cardiovascular disease risk factors and potential mechanisms of action: a dose-response study, Am. J. Clin. Nutr, 2008, 88, 651–659.