A cornerstone of vegan, raw, and Paleo diets, nuts may very well be the perfect snack—they’re whole, plant-based, and packed with protein and fiber. Plus, they’re easy to eat on the go. Problem is, it’s hard to feel guilty about going overboard when you know something is so good for your health.
For example, people who consume five or more servings of nuts per week have lower levels of disease-causing inflammation than those who never (or almost never) eat nuts, according to research published in the American Journal of Clinical Nutrition. What's more, people who sub in three servings of nuts per week in place of red meat, processed meat, eggs, or refined grains can also experience lower levels of inflammation.
And, in a 2013 study of nearly 190,000 people published in the New England Journal of Medicine, those who ate a one-ounce serving of nuts daily decreased their risk of dying from any cause, including cancer and heart disease, by 20%. “These people also tend to be leaner, which is a curious finding, considering a serving of nuts is 160 to 200 calories,” says study researcher Charles S. Fuchs, M.D., M.P.H., professor of medicine at Harvard Medical School. Fuchs suggests that nuts’ positive effect on energy balance, metabolism, and satiety likely explain how the high-fat snack can actually keep your weight in check.
But this isn’t a free pass to eat peanuts and pistachios by the bagful. “The key is portion size,” says Maureen Tarnus, M.S., R.D., executive director of the International Tree Nut Council Nutrition Research & Education Foundation. “The FDA-qualified health claim for nuts and heart disease recommends 1.5 ounces (about 1/3 cup) per day, and much of the research on nuts and diabetes, weight, and so on, has looked at that same amount.”
In terms of variety, “pick whatever nut you like,” advises Fuchs. “They all appear to be providing comparable benefits.” Still, some nuts offer unique health-boosting bonuses, like strengthening bones, boosting braining health, or improving eyesight, so zero in on these eight.
If snacking presents a once-you-pop-you-can’t-stop problem, pick pistachios. The tiny green nuts afford you the biggest serving size—49 kernels—and since they’re typically sold in-shell, the work that goes into peeling the nuts slows down consumption. Pistachios are also the nut with the highest levels of three eyesight-boosting antioxidants: lutein, zeazanthin, and beta-carotene.
Almonds offer up more fiber than any other nut, which may help explain why participants in a Purdue University study who added 1.5 ounces of the nut to their daily diets reported less hunger and did not gain weight despite taking in 250 extra calories. Almonds also contain 75mg of calcium per serving—a fourth of what’s in a cup of skim milk.
Since they grow underground, peanuts are technically legumes, but offer the same health and nutrition benefits as tree nuts. At 7g per serving, peanuts are the big winner when it comes to protein. They’re also of the best sources of arginine. The amino acid promotes the production of nitric oxide, which helps dilate blood vessels and may help lower blood pressure.
Walnuts’ claim to fame: they’re the only nuts that are a significant source of alpha-linolenic acid (ALA), a plant-based omega-3 fatty acid that boosts heart and brain health. What’s more, a walnut-rich diet may reduce the risk of Alzheimer’s disease, as the nut’s high levels of antioxidants protect the brain from degeneration, according to research published in the Journal of Alzheimer’s Disease.
Brazil nuts are best known for their selenium content—a 1-ounce serving delivers 777% of the recommended daily intake of the antioxidant. Selenium fights free radicals—particles that damage cells and cause diseases like cancer and heart disease—plays a role in thyroid function and reproduction, and may bolster the immune system, so stock up during flu season.
In addition to being the nut that’s lowest in fat, cashews are also an excellent source of copper—one serving takes care of almost 100% of your daily intake of the mineral. Copper does a number of things in the body: it helps absorb iron (and make energy); manufacture red blood cells; and form collagen, a key component of bones and connective tissue.
Hazelnuts are big on folate—a lack of the B-vitamin, found primarily in leafy green vegetables, may cause mental health issues, like depression. Hazelnuts also have a higher concentration of proanthocyanidins (PACs) than any other nut. PACs are antioxidant plant compounds that may lower blood pressure, keep blood vessels and arteries healthy, and reduce the risk of heart disease.
Think outside the pie. Pecans are the nuts with the highest concentration of antioxidants, especially vitamin E, according to research published in the Journal of Agriculture and Food Chemistry. Joined by foods like blueberries and beans, food potent in antioxidants protect against cell damage and decrease the risk of cancer, cardiovascular disease, and neurological diseases like Alzheimer’s.