Nuts are one of the high potassium foods. Their ratio of potassium to sodium is usually much more than the 3 to 1 ratio recommended, if they are not salted. A small serving of nuts can provide more potassium than the often mentioned banana. By providing so much potassium, and so little sodium, they contribute to lowering blood pressure and increasing bone density. Other nutrients in nuts also reduce coronary heart disease (CHD).
In previous posts we have discussed how high potassium foods improve blood pressure, reducing the chance of heart disease and stroke. Nuts contribute more than just potassium to cardiac health, though. A large number of studies have found multiple beneficial effects of nuts on coronary heart disease directly, and on the intermediate markers of heart health often used, such as various lipids and cholesterol.
How Nuts Benefit The Heart
A recent review (1) provides a nice discussion of what and how nutrients in nuts can contribute to heart health. Nuts are high in minerals other than sodium. One mineral that is thought to be especially important for the heart is magnesium, which is high in all nuts. Other important components are the vitamins, the phytosterols, and the fats in nuts. The fats in nuts are especially helpful and we will discuss them more extensively next week.
The vitamins that are especially plentiful in nuts are folate and Vitamin E. The folate present in nuts detoxifies homocysteine which contributes to narrowing and closing off arteries with clots. Doctors often measure homocysteine to assess the risk of CHD.
The antioxidants Vitamin E (tocopherol) and polyphenols are present in large amounts. Alpha tocopherol is present in most nuts and gamma tocopherol is especially prevalent in walnuts. Although researchers have not studied gamma tocopherol as much as alpha tocopherol, gamma tocopherol is beginning to emerge as an important substance in the prevention of arterial plaques.
Phytosterols improve heart health and decrease heart disease by blocking cholesterol absorption. Cholesterol is absorbed from the intestines in small packets called micelles. Since the phytosterols have a greater affinity for the micelles than cholesterol, they kick the cholesterol out of the micelles. This prevents cholesterol from being absorbed.
The Fats In Nuts
The fats in nuts are especially important heart disease fighters. The major fat culprits in CHD are saturated fat and trans fat. Nuts contain no trans fat and only small amounts of saturated fat. The fats in nuts are mostly polyunsaturated and monounsaturated fats. Next week we will discuss the effect of these fats on heart disease more thoroughly, but worth mentioning is the beneficial effects of these fats, especially the polyunsaturated. These fats lower the intermediate markers of heart disease – LDL and total cholesterol. This results in less heart disease itself. The polyunsaturated fat, ALA (alpha-linolenic acid), in walnuts may be especially helpful.
The fat in nuts concerns some people. They believe the fat in nuts will lead to fat on the body. But multiple studies have shown no increase in obesity from eating nuts. In some studies, the people who ate the most nuts were at a lower risk of obesity.
To Find Nutrient Tables
To find a table of the potassium and sodium content of nuts click the tab labelled “Links to Food Potassium Tables” at the top of the page. Then click the link to the nuts table.
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1. Health benefits of nut consumption. Ros E. Nutrients. 2010 Jul;2(7):652-82. doi: 10.3390/nu2070683. Epub 2010 Jun 24. Review. PMID:22254047
