15 Superfoods and the Scientific Reasons to Eat Them

Avocado is a key component to a modern-day brunch staple, avocado toast, and contains a bevy of nutrients worth celebrating.

According to the U.S. Department of Agriculture (USDA), ½ an avocado provides 29 milligrams (mg) of magnesium, or about 7 percent of the DV. Magnesium plays a role in regulating blood pressure and blood sugar, and magnesium deficiency is associated with a higher risk for type 2 diabetes, according to the NIH. Avocado also provides fiber (6.8 mg per ½ fruit, offering 24 percent of DV), along with heart-healthy polyunsaturated and monounsaturated fat. An advisory published by the American Heart Association noted that replacing saturated fat (from sources such as butter) with the fats found in foods such as avocado can help reduce the risk for heart disease.

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Exotic fruits have long been revered as superfoods for their nutritional content and medicinal properties. Research shows that pomegranates, for example, may bolster heart health, and make a good candidate for dietary supplements that could prevent cardiovascular disease, according to one article.

Blueberries are at the top of almost every superfood list, but just about any edible berry is worthy of superfood status. While all differ in nutritional value, blackberries, cranberries (the fresh, not dried, variety), strawberries, and raspberries, to name a few, are low-calorie, high in fiber, and packed full of antioxidants that help fight against cancer-causing free radicals, notes one study.

Blueberries, in particular, have a high number of anthocyanin pigments, which not only give them their rich color, but also act as powerful antioxidants that may lower the risk of diabetes, heart disease, and degenerative diseases like Alzheimer’s, according to one review.

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Named after the cross-like appearance of their petals, per the Academy of Nutrition and Dietetics, cruciferous vegetables are heralded for health benefits such as lowering the risk of cancer and preventing heart attacks and stroke. Broccoli, Brussels sprouts, bok choy, cauliflower, cabbage, and maca (a Peruvian plant popular in North America as an energy booster, per research) are all types of cruciferous veggies that are full of fiber. Not only is fiber good for you, but it makes you feel full longer, which could help with weight loss, according to the American Society for Nutrition.

This group of veggies contain compounds called indole glucosinolates, which help maintain the balance of healthy bacteria in your gut, and could reduce or prevent digestive conditions such as ulcerative colitis and Crohn’s disease, according to a preliminary study on mice. More studies in humans are needed, though.

Unlike many animal products high in saturated fats, such as red meat and processed meats, that can raise the risk of heart disease, fish is full of protein and rich in healthy fats. Omega-3 fatty acids — namely the type you get from seafood including fish — are particularly beneficial to our bodies, notes the NIH. These types, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are used more efficiently than the third type of omega-3, alpha-linolenic acid (ALA), which comes from plant sources such as flaxseed and nuts, research has shown. Overall, omega-3s can help play a role in reducing your risk of heart disease, cancer, and Alzheimer’s, as well as aiding infant development, according to the NIH.

A study found omega-3 fatty acid intake across the United States was lower (and much lower in women and children) than the recommended amounts, which, the authors wrote, is “putting vulnerable populations at potential risk for adverse health outcomes.” The American Heart Association (AHA) recommends consuming at least two servings of fish, 3 ounces (oz) each, per week, noting that fattier fish like salmon, sardines, mackerel, and herring are especially healthy.

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They may be pungent (some even bring us to tears), but allium vegetables — chives, onions, garlic, leeks, and the like­­ — deliver potent health benefits that contribute to their superfood status. Plus, they’re delicious. Once used to ward off the evil eye, garlic also has antibacterial and antiviral properties, according to research.

Studies have found allium vegetables may play a role in preventing cancer, and garlic in particular may benefit people living with diabetes, high cholesterol, and high blood pressure, according to a meta-analysis.

For centuries, mushrooms have been considered a superfood and are still used in traditional Chinese medicine to cleanse the body and promote longevity. Researchers have long studied the antibacterial, antioxidant, and anti-inflammatory properties of mushrooms, and mycotherapy — the use of mushrooms as medicine — is used as a complementary treatment for breast cancer. A 2022 review found mushrooms to have some anticancer effects, but the authors noted that this is based on only a couple of studies, and more robust clinical research is necessary.

RELATED: Will Drinking Mushroom Tea Make You Healthier?

Wellness gurus tout different superpowers for each nut — almonds for heart health, cashews for cognition, Brazil nuts for cancer — but all are a great source fat, fiber, and protein (ones encased in sugar or salt are on the less healthy side), notes the Harvard T.H. Chan School of Public Health. Seeds like flaxseeds, chia seeds, and hemp seeds are easy to incorporate into your diet and are packed with vitamins and minerals.

While nuts are high in fat, they also keep you feeling full longer, and research has linked nuts to a lower risk of weight gain and obesity. Walnuts are at the top of the “supernut” list, with their antioxidant power helping to prevent diseases like certain types of cancer, according to one study.

Generally, the darker the color of a vegetable, the more nutrients it contains, says Wolfram. Dark, leafy greens like arugula, kale, collard greens, spinach, lettuce, and Swiss chard get their vibrant colors from chlorophyll, which keeps plants healthy, and the dietary fiber found in dark greens can decrease the risk of colorectal cancer, according to the American Institute for Cancer Research. Carotenoids, another type of plant pigment, also act as antioxidants and are associated with lower cancer incidence, according to one review.

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Like superfoods, ancient grains are another buzzword that markets certain grains and seeds — like buckwheat, farro, and quinoa — as more nutritious than modern crops. The Whole Grains Council notes that grains that have been “largely unchanged over the last several hundred years” are considered ancient grains.

But to reap the benefits of grains, you don’t need to overthink it. Simply choose whole over refined grains. Compared with white rice, for example, brown rice provides more nutrients and fiber, according to the Harvard T.H. Chan School of Public Health.

Also, barley, bulgur wheat, brown rice, and oats are common whole grains that have the whole nutritional package, notes the Harvard school, and are packed with fiber, antioxidants, and vitamins. Brown rice specifically has a variety of phenolic acids with antioxidant properties that may help prevent conditions like type 2 diabetes, cancer, and heart disease, per one study.

Citrus fruits have been crowned as superfoods because of their fiber and vitamin C content. The sweet and sour bite of citrus fruits like grapefruit, oranges, lemons, and limes is also low in calories and high in water. One study found that adults ages 50 and older who ate oranges every day had a 60 percent less chance of developing macular degeneration compared with those who didn’t eat oranges.

RELATED: 8 Best Fruits for People With Diabetes

Kimchi, kombucha, kefir, miso, sauerkraut, and yogurt are all fermented (or preserved) foods that are rich in probiotics.

Probiotics are “healthy” bacteria, and the body produces millions of them, making up the larger community called the microbiome, notes the National Center for Complementary and Integrative Health.

Research from 2021 suggested that probiotics may contribute to a healthy gut microbiome and play a role in disease prevention. Probiotics are found in supplements but also foods, many of them fermented. People with chronic inflammatory conditions such as Crohn’s disease, ulcerative colitis, and rheumatoid arthritis may have fewer strains of good bacteria in their gut. Consuming yogurt with live bacteria may improve microbiota diversity, according to the Harvard T.H. Chan School of Public Health.

Unlike its sweeter milk and white chocolate counterparts, dark chocolate may offer health benefits. The cacao in dark chocolate is full of antioxidants, which may play a role in cancer prevention, heart health, and weight loss, according to research. A 1- or 2-oz serving of dark chocolate (with a minimum of 70 percent cacao) a day may have other health benefits, such as improving cognition, preventing memory loss, and boosting mood, reported one small study.

RELATED: 8 Healthy Reasons to Eat Dark Chocolate

Sweet potatoes have long been on the superfoods list, and for good reason. Carrots, beets, parsnips, potatoes, and yams are all types of root vegetables that have sustained human life for hundreds of years — and through many a harsh winter.

Nutritious, easy to grow, and with an exceptionally long life span (some can last months, if stored properly), root vegetables are packed with healthy carbs and starches that provide energy, according to the Harvard T.H. Chan School of Public Health.

One review suggested that this root veggie may contribute to preventing diabetes, obesity, cancer, and other health conditions thanks to their anti-inflammatory, antioxidative, and antimicrobial properties.

As a bonus, root veggies including sweet potatoes are also gluten-free, making a great dietary alternative for those who are gluten intolerant or have celiac disease.

As far as superfoods go, the beans and legume family possess the power of plant-based protein. Unlike food from many animal sources, beans and legumes are low in saturated fats — which can raise cholesterol levels and contribute to heart disease — and yield health benefits that animal products don’t, according to the AHA.

Chickpeas, edamame, lentils, peas, and the thousands of other bean types are densely packed with nutrition, and research has found the high levels of fiber and vitamins in them can help with weight loss and regulating blood sugar levels, according to one study. Peanuts are also in the legume family as well, making this nut look-alike a great, low-carb snack, per Harvard Health Publishing.