It would most definitely be an understatement to say that walnuts are a nutrient-rich snack. However, the benefits of walnuts for your health go far beyond their fiber, vitamins, and minerals source.
There is so much interest in this particular nut that for the past 50 years, researchers and business leaders have met yearly at the University of California, Davis, for a conference on walnut health to examine the most recent studies. As a result, English walnuts are the most popular and extensively studied variety of walnut.
Below are 12 health benefits of walnuts supported by science.
1. Loaded with Antioxidants
Compared to other standard nuts, walnuts have the highest antioxidant activity. Melatonin, Vitamin E, and plant chemicals called polyphenols—abundant in the papery skin of walnuts—are the sources of this activity.
An early, small study on healthy people found that having a meal high in walnuts inhibited the oxidation of “bad” LDL cholesterol after eating, whereas eating a meal high in refined fats did not. This is significant since oxidized LDL can accumulate in your arteries, leading to atherosclerosis.
2. Exceptional Plant Source of Omega-3s
Walnuts provide 2.5 grams of omega-3 fat per 1-ounce (28-gram) serving, which is significantly more than any other nut. Alpha-linolenic acid (ALA for short) is an essential omega-3 fatty acid found in plants, including walnuts. Since it is an essential fat, you must include it in your diet.
The Institute of Medicine states that for men and women, 1.6 and 1.1 grams of ALA daily is a healthy intake. One serving of walnuts fulfills that recommendation. According to observational studies, every gram of ALA you consume daily reduces your risk of dying from heart disease by 10%!
3. May Reduce Inflammation
Oxidative stress can produce inflammation, the basis of many diseases such as cancer, type 2 diabetes, Alzheimer’s disease, and heart disease. Walnuts’ polyphenols can aid in the battle against inflammation and oxidative damage. In particular, ellagitannins (a subclass of polyphenols) may be very important.
Helpful bacteria transform ellagitannins in your gut into substances known as urolithins, which have been shown to inhibit inflammation. In addition, walnuts’ arginine amino acid, magnesium, and ALA omega-3 fat may help reduce inflammation.
4. Encourages Gut Health
According to studies, you’re more likely to have a healthy gut and general health if your gut is home to various bacteria and other microbes that support good health (your gut microbiota). Conversely, your risk of cancer, obesity, and heart disease can increase due to an unbalanced microbiota, which can lead to inflammation and infection in other body parts.
Your microbiota’s composition can be dramatically influenced by what you eat. One way to promote the health of your microbiota and gut is by eating walnuts. For example, an increase in good bacteria was observed in 194 healthy people who consumed 43 grams (1.5 ounces) of walnuts daily for eight weeks, compared to when walnuts were not consumed. This included a rise in the bacteria that create butyrate, a lipid that nourishes and improves the health of your gut.
5. May Lower the Risk of Some Cancers
According to animal, test-tube, and human observational studies, walnut consumption may lower your risk of developing prostate, colorectal, and breast cancer. This is because walnuts are high in polyphenol ellagitannins, as was already mentioned. These can be transformed into substances known as urolithins by specific gut microorganisms.
Eating walnuts may partly help prevent colorectal cancer because urolithins have anti-inflammatory effects in your gut. In addition, the anti-inflammatory properties of urolithins may potentially aid in preventing other cancers.
Urolithins also have properties similar to hormones, which allow them to block hormone receptors in the body. As a result, your risk of developing hormone-related cancers, specifically prostate and breast cancer, may be lowered. However, to confirm the effects of consuming walnuts on reducing the risk of these and other cancers and to understand all the processes by which they may aid, more research on humans is needed.
6. Aids in Weight Management
Despite the high caloric content of walnuts, studies indicate that the amount of energy absorbed from them is 21% lower than predicted, given their nutritional makeup. Additionally, eating walnuts may aid in appetite control.
In a highly controlled experiment involving ten obese participants, consuming a smoothie containing roughly 1.75 ounces (48 grams) of walnuts once daily for five days reduced appetite and hunger compared to drinking a placebo beverage with identical calories and nutrients.
Brain scans also revealed that after five days of ingesting the walnut smoothies, the participants’ activation in a part of the brain that aids in resisting highly tempting food cues, like pizza, cake, and French fries, had increased. This offers some preliminary insight into how walnuts may help regulate appetite and weight. However, more extensive and longer-term research is still required.
7. May Reduce Your Risk and Aid in Managing Type 2 Diabetes
Walnuts may help control weight. This is one reason observational studies link them to a lower risk of type 2 diabetes. Your risk of diabetes and high blood sugar is increased by being overweight. However, consuming walnuts may support blood sugar regulation through pathways unrelated to weight management.
An 8% reduction in fasting blood sugar was seen in a controlled study of 100 individuals with type 2 diabetes who consumed one tablespoon of cold-pressed walnut oil daily for three months, along with their regular diabetes medications and a healthy diet.
Additionally, the consumption of walnut oil was associated with a roughly 8% reduction in hemoglobin A1C (three-month average blood sugar). Fasting blood sugar and A1C did not improve in the control group, and there was no weight change in either group.
8. May Reduce Blood Pressure
A significant risk factor for heart disease and stroke is high blood pressure. According to several studies, eating walnuts may reduce blood pressure, both in healthy people and in people with elevated blood pressure who are under stress. However, this impact was not shown in other investigations. In addition to other diets, the four-year PREDIMED study investigated a Mediterranean diet supplemented with 28 grams (1 ounce) of mixed nuts daily, of which half were walnuts, in about 7,500 adults at high risk of heart disease.
Diastolic blood pressure decreased by 0.65 mmHg more in research participants following the nut-enriched Mediterranean diet (bottom number) than in participants following a similar heart-healthy control diet without nuts. This implies that adding nuts to a heart-healthy diet may somewhat enhance its effects on lowering blood pressure. This is crucial because it is believed that even minor blood pressure variations can significantly impact your chance of dying from heart disease.
9. Encourages Healthy Aging
Being physically healthy becomes increasingly important as you age to keep your independence and mobility. Healthy dietary practices are one way to help you preserve your physical ability.
Over 50,000 older women participated in an observational study spanning 18 years, and the results showed that those with the cleanest diets had a 13% lower chance of physical impairment. Among the foods that contributed most strongly to a healthy diet were walnuts. Despite having a lot of calories, walnuts are rich in healthy fats, fiber, vitamins, minerals, and plant chemicals that may support healthy aging.
10. Encourages Optimal Brain Function
A walnut’s shell may resemble a miniature brain by coincidence, but research indicates that this nut actually may benefit your brain. Studies on animals and test tubes have revealed that walnut components, including polyunsaturated fat, polyphenols, and vitamin E, may help lessen oxidative stress and inflammation in the brain.
In a 10-month Alzheimer’s disease trial, rats given 6–9% of their daily calories as walnuts (equivalent to 28–45 grams or 1-1.5 ounces in humans) showed significant gains in learning abilities, memory, and anxiety reduction compared to a control group that received no walnuts. In addition, eating walnuts has improved brain function in older adults, including quicker processing times, greater mental flexibility, and improved memory.
Even while these findings are promising, more research on how walnuts affect human brain function is required before any conclusions can be drawn.
11. Promotes Male Reproductive Health
Reduced sperm function has been associated with typical Western diets, which are high in refined grains, sugar, and processed foods. Consuming walnuts could benefit male fertility and sperm health. Compared to males who did not eat nuts, 117 young, healthy men who consumed 2.5 ounces (75 grams) of walnuts daily for three months saw improvements in sperm form, vitality, and movement.
Moreover, animal studies have found that eating walnuts may lessen oxidative damage to sperm membranes. Although further research is required to validate these effects, eating walnuts is a good idea if you’re a man worried about fertility.
12. Enhances Blood Fats
Heart disease risk has long been associated with higher “bad” LDL cholesterol and triglyceride levels. It has repeatedly been demonstrated that eating walnuts regularly lowers cholesterol levels. In a recent study, consuming 1.5 ounces (43 grams) of walnuts per day for eight weeks resulted in a 5% reduction in total cholesterol, a 5% reduction in LDL cholesterol, and a 5% reduction in triglycerides as compared to not eating walnuts.
Apolipoprotein-B, a marker of the number of LDL particles in your blood, also fell by about 6% in the walnut eaters. Apolipoprotein-B is a significant risk factor for heart disease when it is elevated.
Widely Available and Simple to Include in Your Diet
Walnuts are available in all supermarket stores. Browse the baking aisle for raw walnuts, the nut aisle for roasted walnuts, and the specialty oils aisle for cold-pressed walnut oil.
It’s helpful to know how to convert serving sizes used in research so you can compare your portion sizes. For example, each of the following servings, which contain about 190 calories, is relatively equivalent: 1-ounce shelled walnuts =1/4 cup =28 grams = one small handful =12–14 halves.
Although it’s easiest to consume walnuts as a snack one at a time, there are many delicious ways to incorporate them into dishes. Here are some suggestions for including walnuts in your meals:
- Sprinkled over fruit or leafy green salads.
- Finely ground for use in sauces and dips.
- Chopped and added to scones and whole-grain bread.
- Crushed to be applied as a coating to chicken or fish.
- Served on top of yogurt or porridge.
- Chopped, then incorporated into wraps or pita sandwiches.
- Added to a homemade trail mix after being roasted.
- In your preferred stir-fry recipe, lightly browned.
- Roasted, chopped, and added to vegetables or pasta.
- With a vinaigrette dressing as an oil.
However, ensure no one has a walnut allergy before including walnuts in recipes if you’re cooking for visitors.
The Takeaway
Walnuts are very nutrient-dense. As a result, they outperform other standard nuts in antioxidant activity and have substantially better omega-3 fats. This robust nutrient profile helps explain why walnuts provide so many beneficial health effects, including less inflammation and reduced risk factors for type 2 diabetes and heart disease.
Scientists are still learning about how walnut fiber and plant compounds, including polyphenols, may interact with your gut bacteria and benefit your health. As more studies explore the health benefits of walnuts, you’ll likely continue to hear more about them in the years to come. Nevertheless, there are many good reasons to start including them in your diet now.
