Eating nuts helps your heart. Discover how walnuts, almonds and other nuts can help lower your cholesterol when eaten as part of a balanced diet.

By Mayo Clinic Staff

Eating nuts as part of a healthy diet may be good for your heart. Nuts contain unsaturated fatty acids and other nutrients. And they're a great snack food — inexpensive, easy to store and easy to pack when you're on the go.

One drawback to nuts is that they're high in calories, so it's important to limit portions. But choosing nuts instead of a less healthy snack may just help you stick to a heart-healthy diet.

Although a great deal of research suggests that nuts can benefit heart health and reduce the risks of dying early from heart disease and other causes, the evidence is still inconclusive. But, unless you're allergic to nuts, there's no real danger in eating nuts, so you can certainly include nuts as part of your heart-healthy diet.

One way nuts may help your heart health is by lowering the low-density lipoprotein (LDL, or "bad") cholesterol levels. LDL plays a major role in the development of plaque that builds up on the blood vessels. Eating more nuts has also been linked to lower levels of inflammation linked to heart disease.

Eating nuts may also reduce your risk of developing blood clots that can cause a fatal heart attack. Nuts also appear to improve the health of the lining of your arteries.

Besides being packed with protein, 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. Omega-3 fatty acids are found in many kinds of fish, but 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.
  • Fiber. All nuts contain fiber, which helps lower your cholesterol. Fiber makes you feel full, so you eat less. Fiber is also thought to play a role in preventing type 2 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.

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 foods with unhealthy saturated fats, try substituting a handful of nuts or a tablespoon or two of a nut spread. The American Heart Association recommends eating about four servings of unsalted nuts a week. Select raw or dry-roasted nuts rather than those cooked in oil.

A serving is a small handful (1.5 ounces) of whole nuts or 2 tablespoons of nut butter. 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.

The type of nuts you choose to eat probably doesn't matter much. Most nuts appear to be generally healthy, though some may have more heart-healthy nutrients than others. For example, walnuts contain high amounts of omega-3 fatty acids.

Almonds, macadamia nuts, hazelnuts and pecans are other nuts that appear to be quite heart healthy. And peanuts — which are technically not a nut, but a legume, like beans — seem to be relatively healthy.

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
Almonds, dry-roasted 170 14.9 g
Almonds, raw 164 14.2 g
Brazil nuts, raw 187 19 g
Cashews, dry-roasted 163 13.1 g
Chestnuts, roasted 69 0.6 g
Hazelnuts (filberts), dry-roasted 183 17.7 g
Hazelnuts (filberts), raw 178 17.2 g
Macadamia nuts, dry-roasted 204 21.6 g
Macadamia nuts, raw 204 21.5 g
Peanuts, dry-roasted 166 14.1 g
Pecans, dry-roasted 201 21.1 g
Pistachios, dry-roasted 162 13 g
Walnuts, halved 185 18.5 g

Nut oils are also a good source of healthy nutrients, but they lack the fiber found in whole nuts. Walnut oil is the highest in omega-3s.

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.

Sept. 15, 2016