Nuts of all types are part of a healthy eating plan. That’s because nuts contain a myriad of nutrients that promote good health and can even stave off debilitating diseases, such as heart disease. One type of nut, the walnut, often gets less attention than its popular cousin, the almond, but it’s time to give walnuts a second look and think about incorporating them into your diet.
What are walnuts?
You’re probably familiar with walnuts — they’re the nuts that come in a round, tan-colored shell that can seem impossible to crack. The actual nut, should you be fortunate to get that shell open, looks a bit wrinkly — almost like a somewhat-shriveled brain.
Walnuts grow on trees and hence, are called tree nuts. The website The Spruce Eats states that the walnut “is the most widely-consumed nut in the world and has been enjoyed for well over 8,000 years.” Most walnuts (about 99%) in the U.S. are grown in California; some are grown in the Midwest, as well.
There are more than 50 species of walnuts, but the most common varieties are the English, or Persian, walnut, and the California black walnut (this walnut has a particularly hard shell to crack and has a deeper flavor than the English walnut).
What nutrients are in walnuts?
Walnuts have a lot to offer, not only in flavor, but in nutrition. The California Walnut Board describes walnuts as being a “powerhouse of important nutrients for optimum health.” Why? Let’s take a look. Here are key nutrients found in walnuts:
- Heart healthy fats (poly- and monounsaturated fats)
- Protein
- Fiber
- Magnesium
- Phosphorous
- Manganese
- Copper
One ounce (about ¼ cup, or 12 to 14 halves) contains:
- 190 calories
- 4 grams of carbohydrate
- 18 grams of fat (13 grams are unsaturated, 1.5 grams are saturated)
- 4 grams of protein
- 2 grams of fiber
- 0 milligrams of sodium
Nuts are high in calories and that’s due to their fat content (portion control is a must!). However, the good news is that the type of fat in walnuts is good for you. Walnuts have omega-3 fatty acids (types of polyunsaturated fatty acids) that have anti-inflammatory properties.
Also, nuts are low in carbohydrate and contain a respectable amount of protein, making them a good choice if you have diabetes.
Health benefits of walnuts
Here are just a few reasons to add walnuts to your eating plan.
Heart health
One of the main reasons to eat walnuts is to help keep your heart healthy. Heart health is particularly important for people with diabetes who have an increased risk of heart disease.
A study published as a research letter in the journal Circulation on August 30, 2021, looked at healthy, older adults who ate walnuts daily over a two-year period. At the end of the study, total cholesterol levels had dropped, as did LDL (bad) cholesterol. In particular, small dense LDL particles, which are linked to heart disease), decreased.
Previous research supports the heart-health benefits of walnuts. A meta-analysis published in 2018 in The American Journal of Clinical Nutrition studied data from more than 1000 people. The authors compared people who ate a “walnut-enriched” diet to those who ate a control diet. Here’s what they discovered among those who ate a walnut-enriched diet:
- A lower total cholesterol
- A lower LDL cholesterol
- A lower apoprotein B (which is linked to heart disease)
- Lower triglycerides (blood fats)
Of note, this study wasn’t a clinical trial, and doesn’t prove that walnuts were the specific reason that blood lipid levels improved.
Walnuts can offer heart-health protection to people who have diabetes, too. A study in the journal Circulation Research published in 2019 looked at 16,217 men and women with diabetes. Of those who ate five or more servings of tree nuts weekly, there was a lower incidence of heart disease and mortality. The study notes that nuts, in general, have healthy fats, as well as fiber, phytochemicals, plant protein, vitamins, and minerals that may contribute to protection from heart disease, as well as high blood pressure, and cancer.
Diabetes and diabetes prevention
If you have diabetes, you know that the foods you eat impact your blood sugar levels in different ways. Walnuts can be considered “diabetes-friendly” because they have less of an effect on blood sugars compared to other foods.
Walnuts are very low in carbohydrate, the nutrient that raises blood sugar levels more so than protein and fat. Plus, the protein, fat, and fiber in walnuts may help to limit the “spike” in blood sugars that can occur after eating (especially eating foods high in carbohydrate).
And since people with prediabetes or who are at risk of developing type 2 diabetes can also benefit from an eating pattern that is controlled in carbohydrate, it makes sense to swap out some of the high-carb, refined foods that we often eat (such as bread, chips, pasta) for lower-carb, higher-protein foods — including walnuts and other types of nuts. Research shows that eating one ounce of walnuts five or more times weekly was linked with a significantly lower risk of developing type 2 diabetes.
Weight control
It may seem a little strange that eating walnuts — or any type of nut, for that matter — can help you lose and maintain a healthy weight. Yet, surprisingly, research suggests that eating nuts can help with weight loss, probably because of the fat, protein, and fiber content which help you feel full longer. Keep eating nuts once you’ve reached your target weight — doing so can help you maintain that weight and lessen the chances of regaining the weight that you’ve lost.
Bone health
We all want our bones to stay strong and healthy, especially as we get older. People with diabetes, particularly type 1 diabetes, are prone to developing osteoporosis, a disease that weakens bones. Osteoporosis causes bones to become less dense and more likely to break. Walnuts contain copper, a mineral needed to promote bone density; a lack of copper in the diet may contribute to the development of osteoporosis. Besides copper, walnuts contain magnesium and manganese, other important minerals that help promote healthy bones.
Gut health
Eating walnuts can increase certain types of bacteria in the digestive tract, also called the gut microbiome. This microbiome may play a role in overall health. For example, a study published in 2020 in the Journal of Nutrition found that participants who ate walnuts had an increase in gut bacteria that was associated with lower blood pressure, total cholesterol, and non-HDL cholesterol. Other research suggests that eating walnuts enhances butyric acid-producing bacteria that maintains colon health.
Brain health
We all want a healthy brain (who wouldn’t?). Eating walnuts can help! According to a study published in 2020 in the journal Nutrients, walnuts contain substances with strong antioxidant and anti-inflammatory properties. People who included nuts, especially walnuts, in their eating plan, had few symptoms of depression, for example. Also, people who ate a Mediterranean-style diet that was supplemented by nuts had a reduced risk of stroke (by about 50%) compared to a control group.
A diet that incorporates foods rich in antioxidants, including walnuts, may help sustain cognitive function, such as memory, concentration and information processing.
Fitting walnuts into your eating plan
Interested in adding walnuts to your diet? Here are a few pointers that can help:
- A small handful of walnuts pairs well with a small piece of fruit for a pick-me-up snack.
- Sprinkle chopped walnuts onto your salad, oatmeal, or yogurt.
- Roasted walnuts are great added to vegetables, pasta, and rice.
- Ground walnuts can substitute for breadcrumbs for chicken, fish, and meat.
- For added brain health benefits, eat walnuts with blueberries.
Speaking of walnuts and blueberries, give this delicious recipe for Spring Greens with Blueberries, Walnuts, and Feta Cheese a try!
Want to learn more about diabetes and nuts? Read “Nuts and Health” and check out our “Seed and Nut Nutrition Chart.”
