Walnuts: A bite-sized natural snack
After the fall harvest season, nuts make their way into some of our favorite holiday treats, including fruitcake and cookies, and get seasonal makeovers with spiced and candied varieties. Walnuts are one favorite nut of the season. Although some ways of eating them aren’t the healthiest (maybe skip the sugar coating), the nuts themselves are chock full of goodness.
“For me, I love to eat, and eat foods that are enjoyable,” says Libby Mills, RD, spokesperson for the Academy of Nutrition and Dietetics. “Ask my tastebuds: Eating walnuts is fun! Adding walnuts into our diet helps us enjoy the healthful foods we make, cook more healthfully, and eat vital nutrients we need for good health.” After all, they’re one of the healthiest nuts you can eat.
Here’s everything you need to know about these bite-sized natural snacks, including walnut calories, nutrition facts, and health benefits. Plus, check out some quick and easy walnut recipes.
Why walnuts are growing in popularity
Nuts, in general, have been trending up, according to market research—and this includes walnuts. Production of walnuts increased by 37 percent from 2008-2009 to 2018-2019, according to the International Nut and Dried Fruit Council. Walnuts are native to Central Asia; today the world’s biggest walnut producers are China (40 percent) followed by the U.S. (31 percent).
“More than 99 percent of the walnuts in the U.S. are grown in California’s central valley,” says Donald Norene, a walnut grower and member of the California Walnut Board. (The California Walnut Board represents walnut growers and funds educational programs and research on walnuts.)
Between Feb. 24 and Aug. 9, 2020 (the height of the Covid-19 pandemic when Americans were snacking and baking in abundance), Norene says walnut sales were up 16.8 percent from last year, and he expects it to continue in 2021.
“In 2021, we anticipate these trends to continue, along with walnuts being used more in snack items like seasoned walnuts, bars, and trail mixes as consumer demand for nutrient-rich snacks continues,” he says.
How walnuts are grown
After a walnut tree is planted, it takes four to five years for it to grow into a tree suitable for harvesting, Norene says. Then, “harvest begins every August and lasts through early November.” Commercial harvesting of walnuts in California involves mechanical shakers that literally shake the trees until the nuts fall to the ground to be gathered up.
“As part of processing, the green protective outer hull is removed, and the nut is dried to an optimum moisture level to protect its quality during storage,” Norene says. “Shelled walnuts are mechanically cracked and the kernels—the part we actually eat—are screened according to size and color, and hand-sorted to ensure quality according to strict USDA (United States Department of Agriculture) standards.”
Different varieties of walnuts
Although there are several types of walnut trees, including the California black walnut, the majority of the walnuts we eat are from the English walnut tree (scientific name Juglans regia), also sometimes called the Persian walnut.
“There are over 30 varieties of walnuts, but the vast majority of what you’d find in stores are one of three main varieties [of English walnuts]: Chandler, Tulare, and Howard, which make up nearly 84 percent of walnuts in the U.S.,” Norene says. “However, the walnuts consumers find in the store are packaged according to size and color standards.”
Walnut nutrition facts
This low-carb, fiber-rich nut is mostly made up of fat (65 percent) and protein (15 percent). This is the nutritional value per ounce of walnuts (14 halves) and their daily value.
Calories: 185 (9 percent Daily Value)
Total fat: 18.5 g (28 percent DV)
Fiber: 1.9 g (8 percent DV)
Protein: 4.3 g (9 percent DV)
Carbs: 3.9 g (1 percent DV)
Sodium: 0.6 mg (0 percent DV)
Potassium: 125 mg (4 percent DV)
Mills breaks down the importance of these nutrients and other notable nutrients found in walnuts:
Nuts, including walnuts, are rich in protein. “We need protein for building and maintaining muscles, hair, fingernails, connective tissue, and even hemoglobin [in red blood cells], which carries oxygen to every part of our body,” Mills says. Plus, “in a time when our attention is focused on strengthening our immunity, it’s reassuring to know the protein we eat can be made into virus and bacteria-fighting antibodies.”
Protein also helps regulate other processes in our body, she says.
“Walnuts are mostly polyunsaturated fat—the mono and polyunsaturated fat in walnuts can lower LDLs (bad cholesterol) and triglycerides,” Mills says. “When saturated fat is displaced by polyunsaturated fat, our risk of heart disease, stroke, and heart attack goes down.”
“Walnuts have alpha-linolenic fatty acid [ALA] which converts to omega-3s in our body,” Mills says. “They help reduce inflammation in the body, which can be a contributor to heart disease, cancer, and other diseases. These fatty acids help our blood vessels relax which can reduce blood pressure.” We can only get omega-3s from food, she says.
Just how much do we need of this good stuff?
“While the recommended dietary allowance [for omega-3s] is 1.6 mg for men and 1.1 mg for women a day, what we need may be between 200-500 mg a day,” Mills says. “Per 1 ounce of walnuts, or 14 halves, there is 2,579 mg omega-3s.”
“While a small amount compared to the daily value, walnuts are high in gamma-tocopherol, a form of vitamin E that likewise is not as abundant in our bodies, but is starting to get a lot of attention,” Mills says.
“Current research is looking at how gamma-tocopherol may protect the brain against decline and cellular damage, the gut from free-radical damage, and the cardiovascular system from risk factors like high cholesterol by reducing inflammation. Research is seeing that tocopherols may help fight cancer by slowing cellular growth,” she says.
“Most Americans are not getting the recommended 30 to 38 grams a day for men and 21 to 25 grams a day for women,” Mills says. “Dietary fiber doesn’t always get the credit it deserves, however maintaining normal bowel function can’t be underestimated. Eating fruits, vegetables, legumes, whole grains, nuts, and seeds makes getting fiber easy.”
Walnuts are an excellent source of copper, providing just under 0.5 mg per ounce. Copper forms enzymes in the body that help make energy, promote healthy brain activity, and regulate the immune system, among other functions, Mills says.
“Walnuts have 42 percent of the daily value of manganese,” Mills says. Manganese helps metabolize carbs, sugar, and cholesterol. “It also plays a role in reproduction, bone formation, our immune response, and the deactivation of free radicals.”
“Walnuts have 11 percent of the daily value of magnesium,” Mills says. “Magnesium has many functions in the body, including the regulation of muscle and nerve function, blood sugar, and blood pressure. But it also helps our body make protein such as muscle and DNA, as well as bones.” (Here’s how to tell if you have a magnesium deficiency.)
“Vitamin B6 helps our bodies make and store glucose [sugar] as well as make hemoglobin for red blood cells,” Mills says. “Vitamin B6 plays a role in brain development and how we feel. How well our immune system functions also depend on vitamin B6.”
“Our body needs dietary sources of zinc every day because we don’t have a way to store this mineral,” Mills says. “Zinc plays a role in immune function. It also helps the body make protein such as muscle and DNA. Zinc aids in from healing from cuts or scrapes. And zinc helps our cells function properly and divide.” (Got a cold? Try these foods high in zinc.)
“Phosphorus is part of our bones, teeth, cell membranes, and our cells’ reproductive code, DNA and RNA,” Mills says.
“In cells, thiamin is essential for making energy, which is then used for cell growth, development, and normal function,” Mills says.
“Folate helps in the metabolism of amino acids and the making of our genetic code—DNA and RNA in cells,” Mills says. “When cells are rapidly reproducing for growth, such as during pregnancy and childhood, folate is vital.” Folate may also help reduce depression and other mental health disorders, she says.
“Iron is an important part of hemoglobin [a protein in red blood cells] which helps carry oxygen from our lungs to cells throughout our bodies,” Mills says. “Walnuts contain non-heme iron, which is less easily absorbed than heme-iron form meat, poultry, and seafood,” she says.
“But we can enhance our absorption of either form of iron by eating them with foods that contain vitamin C, like citrus, tomatoes, peppers, and strawberries,” says Mills.
Are walnuts good for you?
Need more reasons to snack on nuts? “Walnuts offer a variety of nutrients and health benefits, including decreased risk for cardiovascular disease, certain cancers, and cognitive impairment,” says registered dietitian Kristen Smith, a spokesperson for the Academy of Nutrition and Dietetics. Smith also mentions that walnuts are rich in omega-3s.
“Walnuts are a rich source of omega-3 fatty acids, which offer anti-inflammatory benefits and may help improve cardiovascular risk factors by decreasing LDL cholesterol and blood pressure.”
Walnuts contain higher amounts of antioxidants than most other tree nuts, she says. And specifically, “walnuts are the only tree nut that contains significant amounts of alpha-linolenic acid (ALA), a type of plant-based omega-3 fatty acid. It is not common for foods to be rich in ALA,” Smith says.
May help with weight loss
Although they are high in calories, nuts including walnuts have been shown in research to help maintain a healthy weight. In a 2019 study published in BMJ Nutrition, Prevention & Health, increasing consumption of nuts, including walnuts, by half a serving a day lessened the risk of obesity. Like many nut studies, this one was partially funded by nut organizations.
“Walnuts offer a protein-rich snack, which can help aid with satiety,” Smith says. Plus, because they keep you full, you’re less likely to reach for that unhealthy snack later.
Replacing walnuts with less healthy ingredients can also change the way you cook. “Adding walnut pieces to cookies can lessen the amount of less nutritious chips and candies that you need to add,” Mills says. “Using the nut butter can lessen the amount of [regular] butter—a source of saturated fat which can elevate blood cholesterol,” she says.
A great addition to a plant-based diet
Reducing saturated fats in animal products by eating more plant-based products is also good for your heart. Plus, “getting amino acids from plant-based protein like walnuts can help us eat fewer animal proteins; by eating more plant-based proteins we eat more fiber and improve our gut biome,” Mills says. “Walnuts have all the same amino acids as animal proteins, just in different quantities.”
Risks and side effects of walnuts
If you’re allergic to tree nuts, you obviously shouldn’t eat walnuts.
If you’re not sure, be on the lookout for the signs of tree nut allergy, including abdominal pain, difficulty swallowing, itching, or shortness of breath. More seriously, a life-threatening reaction called anaphylaxis might also include trouble breathing, dizziness or fainting, hives, and a rapid heartbeat. Call 911 right away and give yourself an epinephrine shot (EpiPen) if you have one.
Because walnuts are high in calories, they should be eaten in a moderate amount. “Because walnuts are 66 percent fat, they are calorie-dense,” Mills says. “Eating too many calories, even those with lots of nutrients and health benefits, can add up to weight gain.”
Stick to an ounce (14 halves) at a time. “A handful, or one ounce, is considered a serving,” Smith says. “Aim to include a variety of nuts, including walnuts, into your diet several days throughout the week,” Mills says.
How to eat walnuts
With versatile walnuts, the possibilities are endless. Eat them on their own as a nutritious snack. Or, “if you don’t normally eat walnuts, start by sprinkling chopped walnuts on salads , cooked cereals, dips, or on mixed dishes for a boost of nutrition and added crunch,” Smith says. “Add walnuts to do-it-yourself snack mixes with high-fiber cereal and dried fruit options.”
Registered dietitian and cookbook author Carlene Thomas has more ideas to get that “crunch factor”: Toast walnuts in the oven for 8 to 10 minutes as a breakfast topper for yogurt, cereal, or smoothies. Use them as a crouton alternative in salads. Pulse in a food processor with chickpeas, garlic, and olive oil for a quick walnut hummus. ”
This is a great flavor boost for wraps, sandwiches, or as a dip, Thomas says. For quick “energy balls,” blend walnuts, oats, dates, and vanilla until smooth, and roll. “These are the perfect snack to grab on-the-go,” Thomas says.
Walnuts also can open the door to more plant-based cooking when used as a replacement for animal proteins. “One of my favorite recipes is for walnut balls,” Mills says. “Shaped like a small meatball, they satisfy the texture, savory flavor, and fun of meatballs.
Thomas says you can blend walnuts with mushrooms or beans with seasonings to form a ground beef substitute for chili, tacos, and pasta sauce.
Raw or roasted?
The healthiest walnuts won’t be salted, candied, or roasted with oil. But even dry roasting may have some drawbacks.
“Roasted, toasted, and heated walnuts will compromise the health benefits we can get from walnut’s healthy fats, vitamin E, and antioxidants to some degree,” Mills says. “Eating raw walnuts will be most nutritious because heat-sensitive nutrients are not exposed to roasting, toasting, or other forms heat.” But, whichever way you prefer still makes a healthy choice.
Quick walnut recipes
Here are a couple of quick recipes from Thomas. “I love to use walnuts for an easy homemade pie or tart crust—perfect for this time of year,” she says.
Walnut Crust Recipe
- 1/2 cup of walnut pieces, lightly toasted
- 1 cup of low fat graham cracker crumbs
- 1 egg white
- 1 tablespoon of butter, melted
- 1 tablespoon canola oil
Chop toasted walnuts in food processor. Add cracker crumbs, mix. Whisk egg white until frothy. Add other ingredient and stir. Press into tart pan bake 325 F for 8 minutes.
Dark Chocolate & Sea Salt Seasoned Walnuts Recipe
- 2 cups walnuts
- 2 tablespoon of honey
- 1/4 cup of cocoa powder
- 1/2 teaspoon of sea salt
Heat oven to 350 degrees Fahrenheit. Spread walnuts on a baking sheet and toast for 12 minutes, shaking pan midway through. Remove from oven and cool for 2 minutes. Warm honey for 30 seconds. Drizzle honey on top walnuts and evenly coat with cocoa powder and sea salt. Store in an airtight container in the fridge or freezer.