Nuts and your heart: Eating nuts for heart health
Eating nuts helps your heart. Discover how walnuts, almonds and other nuts help lower your cholesterol when eaten as part of a balanced diet.By Mayo Clinic staff
Eating nuts as part of a healthy diet is 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?
Most studies on people who eat nuts as part of a heart-healthy diet have found that nuts lower the LDL, low-density lipoprotein or "bad," cholesterol level in the blood. High LDL is one of the primary causes of heart disease, so nuts' ability to lower LDL cholesterol seems to be quite beneficial.
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-health benefits of nuts isn't rock solid yet — 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, researchers think 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 fish, but nuts are one of the best plant-based sources of omega-3 fatty acids.
- L-arginine. Nuts also have lots 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.
- Fiber. All nuts contain fiber, which helps lower your cholesterol. Fiber also makes you feel full, so you'll eat less later. Fiber is also thought to play a role in preventing diabetes.
- Vitamin E. Researchers still aren't sure, but it's thought that vitamin E may help stop the development of plaques in your arteries which can narrow them, leading 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.
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. Current guidelines suggest eating 1 to 2 ounces (28.4 to 56.8 grams, or a small handful) of nuts each day. 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 have heart-health benefits. Both coconut meat and oil contain a large amount of saturated fat.
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/13.1 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 (1 g/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||162||13 g (1.6 g/10.8 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 good sources of omega-3 fatty acids and vitamin E, but they lack the fiber in whole nuts. Walnut oil is 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.http://www.mayoclinic.com/health/nuts/HB00085
Recipe: Almond and apricot biscottihttp://www.mayoclinic.com/health/healthy-recipes/NU00294
Dietitian's tip: This twice-baked cookie is a classic with coffee or tea. The whole-wheat and nuts are good sources of manganese (a mineral that helps bone formation) and selenium (an antioxidant important for thyroid hormone function).
MAKES 24 COOKIES
3/4 cup whole-wheat (whole-meal) flour 3/4 cup all-purpose (plain) flour 1/4 cup firmly packed brown sugar 1 teaspoon baking powder 2 eggs, lightly beaten 1/4 cup 1 percent low-fat milk 2 1/2 tablespoons canola oil 2 tablespoons dark honey 1/2 teaspoon almond extract 2/3 cup chopped dried apricots 1/4 cup coarsely chopped almonds
Preheat the oven to 350 F.
In a large bowl, combine the flours, brown sugar and baking powder. Whisk to blend. Add the eggs, milk, canola oil, honey and almond extract. Stir with a wooden spoon until the dough just begins to come together. Add the chopped apricots and almonds. With floured hands, mix until the dough is well blended.
Place the dough on a long sheet of plastic wrap and shape by hand into a flattened log 12 inches long, 3 inches wide and about 1 inch high. Lift the plastic wrap to invert the dough onto a nonstick baking sheet. Bake until lightly browned, 25 to 30 minutes. Transfer to another baking sheet to cool for 10 minutes. Leave the oven set at 350 F.
Place the cooled log on a cutting board. With a serrated knife, cut crosswise on the diagonal into 24 slices 1/2-inch wide. Arrange the slices, cut side down, on the baking sheet. Return to the oven and bake until crisp, 15 to 20 minutes. Transfer to a wire rack and let cool completely. Store in an airtight container.