How often do you eat walnuts? These unassuming brain-shaped nuts aren't always the most popular—but they hold a myriad of health benefits. A 1-ounce serving of walnuts can help boost your brain health, heart health, gut health, and so much more.
Learn all about the nutritional benefits of walnuts and the serving size that dietitians recommend here.
What are walnuts?
- Calories: 185
- Fat: 18.5 grams
- Saturated fat: 1.7 grams
- Cholesterol: 0 grams
- Sodium: 0.6 milligram
- Carbohydrates: 3.9 grams
- Dietary fiber: 1.9 grams
- Protein: 4.3 grams
- Calcium: 27.8 milligrams
- Magnesium: 44.8 milligrams
- Iron: 0.8 milligram
- Potassium: 125 milligrams
"Compared to other tree nuts, walnuts are much higher in the plant source of omega-3 fatty acids," says May Zhu, MBA, R.D., LDN. These fatty acids can't be made in our bodies—we get them from food—but are essential for brain health and cognition, as well as cardiovascular health.
And don't toss the walnut skins aside. Huma Chaudhry, R.D., LDN, adds that the skin of walnuts also contains high amounts of antioxidants that can "help fight inflammation and oxidative damage in the body."
Walnuts hold benefits from your head to your toes, helping support good health in your brain, heart, gut, and more. Here are their top science-backed perks of eating 'em:
They may benefit brain health.
"Walnuts contain nutrients such as healthy fats, antioxidants, and vitamin E, which all contribute to brain health by reducing oxidative stress and inflammation," Zhu explains.
Studies suggest that the nutrients in almonds, hazelnuts, and walnuts could help prevent or even manage Alzheimer's disease5.
"The plant compounds found in walnuts also have been shown to reduce inflammation and oxidative stress in the brain, reducing risk for brain disorders," Chaudhry says. English walnuts (the most popular type) hold multiple phytochemicals6, including high amounts of polyunsaturated fatty acids, which benefit brain health. The polyphenolic compounds in walnuts reduce inflammation of brain cells and improve neurogenesis7, the formation of new neurons in the brain.
One study also discovered that regular consumption of nuts, in general, could be linked to a decreased risk for cognitive decline8.
They may benefit heart health.
"Consumption of walnuts has been linked most notably to supporting heart health," Zhu says. This is because walnuts contain significant amounts of alpha-linolenic acid9 (ALA), which reduces the risk of cardiovascular disease. Eating walnuts instead of foods that have saturated fat could help lower the "bad cholesterol" (LDL) and raise your "good cholesterol" (HDL).
They can help to balance blood sugar.
One study on this topic looked specifically at walnut oil, indicating that consuming walnut oil could improve blood glucose levels11 in people with Type 2 diabetes. Another study12 (conducted on hyperlipidemic patients with Type 2 diabetes) indicated that long-term walnut consumption could reduce fasting plasma glucose and insulin levels.
"The macronutrient combination in walnuts can increase satiety, keeping you full for longer and making it a diabetes-friendly snack," Chaudhry says.
They may help improve sleep quality.
In addition to melatonin, walnuts may help improve your shut-eye thanks to their high magnesium content. A 1-ounce serving contains 11% of your daily magnesium requirement14. Magnesium is an essential mineral that helps your body relax, improving sleep quality. It also helps regulate GABA15, a neurotransmitter that's involved in promoting good sleep.
They may help to promote longevity.
Recent research has shown that walnuts may help improve longevity, as well as helping you age more healthily and gracefully.
She notes that the group that ate more walnuts had a 14% lower risk of death from any cause and 25% less risk of death from cardiovascular disease, plus a gain in about 1.3 years of life expectancy (but it's important to note that this study was funded by the California Walnut Commission).
They may benefit gut health.
In another California Walnut Commission–funded study, 194 healthy adults consumed 1.5 ounces of walnuts each day for eight weeks. They saw an increase in beneficial bacteria22 compared to when not eating walnuts. In a separate study, facilitators also concluded that walnut consumption affected the gut microbiome23.
They may improve metabolic health
Both animal and human studies have indicated that walnuts may help decrease the risk or the progression of conditions25 such as Parkinson's disease, stroke, depression, cardiovascular disease, and Type 2 diabetes. Walnuts can also lower your "bad cholesterol," and the phytomelatonin26 found in walnuts is being studied 26for its anticancer effects27.
They also recommend eating walnuts as a snack on their own (prepackaged walnuts are portioned correctly to enjoy on the go); mixed into granola; or as a crunchy topping on salads, yogurt, or oatmeal.
"Top your breakfast oatmeal or pancakes with walnuts or stuff into baked goods like banana bread or scones," Chaudhry suggests. "I like to roast and chop up walnuts to toss into stir fry, wraps, or use as a crunchy coating for fish and chicken."
You can also try one of these mindbodygreen recipes that incorporate walnuts:
Check out our anti-inflammatory eating guide for more ideas.
Allergies and side effects
Of course, if you're allergic to walnuts, you should leave this food off the menu. Nut allergies can cause anaphylaxis, which can be fatal. Even if you think you're only allergic to other nuts, check with your doctor before consuming walnuts. Chaudhry says tree nuts can be closely related and may cause cross-reactions.
"Younger children should be supervised while consuming walnut pieces to avoid choking," adds Zhu. She also explains that eating too many walnuts might cause GI upset like bloating or diarrhea.
Buying and storage tips
Walnuts have a hard outer shell that can help protect them from most harmful pesticides, so you don't necessarily need to buy them organic if you're looking to save some cash.
Eating raw walnuts (versus nuts that are roasted) gives you more antioxidants. "California-grown, organic English walnuts are a high-quality option," Chaudhry says.
Shelled walnuts should be firm to the touch, not soft or shriveled. Unshelled walnuts should feel full and heavy. Store walnuts in the fridge to keep them fresh, or put them in the freezer for up to one year.
How many walnuts should you eat a day?
Experts say the best serving size of walnuts is 1 ounce, or approximately a handful.
What do walnuts do for your body?
Studies show that the potential benefits of walnuts for your body include better brain health; steadier blood sugar levels; improved quality of life; lower cholesterol; better sleep; improved heart health; and lower disease risk.
What are the benefits of walnuts for females?
The potential benefits of walnuts for females are similar to the benefits of walnuts for males—healthy aging, less insomnia, and decreased risk of cardiovascular disease. There don't appear to be any additional benefits for women's health or hormones specifically.
Walnuts are a powerhouse food to incorporate into your meals and snacks. Ready to reap the benefits of this healthy (and delicious) nut? Learn how they stack up to other popular options, like pecans, here.
Hailey Hudson is a full-time freelance writer and content marketer who lives in Atlanta, Georgia. A former competitive athlete, she now uses her fascination with all things health to find the best ways to support her body while living with several chronic illnesses. Hailey writes for clients like Healthline, Runner's World, Bodybuilding.com, and Hello Fresh.