Mayo Clinic Health Library

Nuts and your heart: Eating nuts for heart health

Updated: 02-04-2011

Eating nuts as part of a healthy diet can be good for your heart. Nuts, which contain unsaturated fatty acids and other nutrients, are a great snack food, too. They're inexpensive, easy to store and easy to take with you to work or school.

The type of nut you eat isn't that important, although some nuts have more heart-healthy nutrients and fats than do others. Walnuts, almonds, hazelnuts — you name it — almost every type of nut has a lot of nutrition packed into a tiny package. If you have heart disease, eating nuts instead of a less healthy snack can help you more easily follow a heart-healthy diet.

Can eating nuts help your heart?

People who eat nuts as part of a heart-healthy diet can lower the LDL, low-density lipoprotein or "bad," cholesterol level in their blood. High LDL is one of the primary causes of heart disease.

Eating nuts reduces your risk of developing blood clots that can cause a fatal heart attack. Nuts also improve the health of the lining of your arteries. The evidence for the heart-healthy benefits of nuts isn't rock solid — the Food and Drug Administration only allows food companies to say evidence "suggests but does not prove" that eating nuts reduces heart disease risk.

What's in nuts that's thought to be heart healthy?

Although it varies by nut, most nuts contain at least some of these heart-healthy substances:

  • Unsaturated fats. It's not entirely clear why, but it's thought that the "good" fats in nuts — both monounsaturated and polyunsaturated fats — lower bad cholesterol levels.
  • Omega-3 fatty acids. Many nuts are also rich in omega-3 fatty acids. Omega-3s are a healthy form of fatty acids that seem to help your heart by, among other things, preventing dangerous heart rhythms that can lead to heart attacks. Omega-3 fatty acids are also found in many kinds of fish, but nuts are one of the best plant-based sources of omega-3 fatty acids.
  • Fiber. All nuts contain fiber, which helps lower your cholesterol. Fiber also makes you feel full, so you eat less. Fiber is also thought to play a role in preventing diabetes.
  • Vitamin E. Vitamin E may help stop the development of plaques in your arteries, which can narrow them. Plaque development in your arteries can lead to chest pain, coronary artery disease or a heart attack.
  • Plant sterols. Some nuts contain plant sterols, a substance that can help lower your cholesterol. Plant sterols are often added to products like margarine and orange juice for additional health benefits, but sterols occur naturally in nuts.
  • L-arginine. Nuts are also a source of l-arginine, which is a substance that may help improve the health of your artery walls by making them more flexible and less prone to blood clots that can block blood flow.

What amount of nuts is considered healthy?

Nuts contain a lot of fat; as much as 80 percent of a nut is fat. Even though most of this fat is healthy fat, it's still a lot of calories. That's why you should eat nuts in moderation. Ideally, you should use nuts as a substitute for saturated fats, such as those found in meats, eggs and dairy products.

Instead of eating unhealthy saturated fats, try substituting a handful of nuts. According to the Food and Drug Administration, eating about a handful (1.5 ounces, or 42.5 grams) a day of most nuts, such as almonds, hazelnuts, peanuts, pecans, some pine nuts, pistachio nuts and walnuts, may reduce your risk of heart disease. But again, do this as part of a heart-healthy diet. Just eating nuts and not cutting back on saturated fats found in many dairy and meat products won't do your heart any good.

Does it matter what kind of nuts you eat?

Possibly. Most nuts appear to be generally healthy, though some more so than others. Walnuts are one of the best-studied nuts, and it's been shown they contain high amounts of omega-3 fatty acids. Almonds, macadamia nuts, hazelnuts and pecans are other nuts that appear to be quite heart healthy. Even peanuts — which are technically not a nut, but a legume, like beans — seem to be relatively healthy. Coconut, which is technically a fruit, may be considered by some to be a nut, but it doesn't seem to have heart-healthy benefits. Both coconut meat and oil don't have the benefits of the mono- and polyunsaturated fats.

Keep in mind, you could end up canceling out the heart-healthy benefits of nuts if they're covered with chocolate, sugar or salt.

Here's some nutrition information on common types of nuts. All calorie and fat content measurements are for 1 ounce, or 28.4 grams (g), of unsalted nuts.

Type of nut Calories Total fat
(saturated/unsaturated fat)*
Almonds, raw 163 14 g (1.1 g/12.2 g)
Almonds, dry roasted 169 15 g (1.1 g/12.9 g)
Brazil nuts, raw 186 19 g (4.3 g/12.8 g)
Cashews, dry roasted 163 13.1 g (2.6 g/10 g)
Chestnuts, roasted 69 0.6 g (0.1 g/0.5 g)
Hazelnuts (filberts), raw 178 17 g (1.3 g/15.2 g)
Hazelnuts (filberts), dry roasted 183 17.7 g (1.3 g/15.6 g)
Macadamia nuts, raw 204 21.5 g (3.4 g/17.1 g)
Macadamia nuts, dry roasted 204 21.6 g (3.4 g/17.2 g)
Peanuts, dry roasted 166 14 g (2g/11.4 g)
Pecans, dry roasted 201 21 g (1.8 g/18.3 g)
Pistachios, dry roasted 161 12.7 g (1.6 g/10.5 g)
Walnuts, halved 185 18.5 g (1.7 g/15.9 g)

*The saturated and unsaturated fat contents in each nut may not add up to the total fat content because the fat value may also include some nonfatty acid material, such as sugars or phosphates.

How about nut oils? Are they healthy, too?

Nut oils are a good source of omega-3 fatty acids and vitamin E, but they lack the fiber found in whole nuts. Walnut oil is the highest in omega-3s. Nut oils contain saturated as well as unsaturated fats. Consider using nut oils in homemade salad dressing or in cooking. When cooking with nut oils, remember that they respond differently to heat than do vegetable oils. Nut oil, if overheated, can become bitter. Just like with nuts, use nut oil in moderation, as the oils are high in fat and calories.

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