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Walnuts Nutrition Helps Both Your Heart & Mood
April 9, 2019
Ever notice that a walnut looks just like the human brain? According to ancient wisdom, this is more than just a coincidence. Considering one of the biggest benefits of walnuts nutrition is the ability to support your most important organ — the brain — walnuts are scientifically proven to be a true “brain food” and one of the healthiest nuts around.
What are health benefits of walnuts? There might be a decent amount of calories in walnuts nutrition, but they also come packed with healthy fats, antioxidants and minerals. According to studies, eating walnuts can help improve your mood, considering they contain one of the highest amounts of omega-3 fats of any nut. In addition to the remarkable things that omega-3 foods can do for your mind, they’re also known to support heart health and fight heart disease by lowering triglyceride levels and reducing dangerous plaque formation in the arteries.
In fact, a recent study published in the Journal of Nutrition found that eating 3 ounces of walnuts a day, along with a healthy diet, promoted positive gut-health changes and reduced the risk of heart disease in obese adults.
Walnuts can be a great tool for weight management too. According to some studies, eating a few walnuts, about four to six halves, before meals decreases people’s perceived level of hunger and may cause them to eat less later in the day. And believe it or not, that’s not all walnuts nutrition has to offer.
Walnuts Nutrition Facts
Would you believe that walnuts (scientific name Juglans regia L.) have been providing crucial nutrients to humans for nearly 8,000 years?
A report on walnuts published in the American Journal of Nutrition states:
Compared to most other nuts, which contain monounsaturated fatty acids, walnuts are unique because they are rich in n-6 (linoleate) and n-3 (linolenate) polyunsaturated fatty acids. Walnuts contain multiple health-beneficial components, such as having a low lysine: arginine amino acid ratio and high levels of arginine, folate, fiber, tannins, and polyphenols.
As you’ve probably noticed, one of the areas where walnuts nutrition shines most is the nut’s high supply of omega-3s benefits, including:
- Omega-3 fatty acids are not only helpful for heart health and brain health, but also for controlling inflammation and improving circulation, memory, thought processing and blood sugar control.
- The human species evolved on a diet that contained high amounts of omega-3 fatty acids — the kind found in wild fish like salmon, flaxseeds, walnuts and wild game — and much less of the polyunsaturated fats called omega-6 fatty acids, found in vegetable oils, packaged foods, and some nuts and seeds.
- In the past several centuries, we have gradually consumed more omega-6s, especially from vegetable oils, and on average much fewer omega-3 foods. Instead of the roughly ideal two-to-one, or even one-to-one, ratio of fats consumed by our ancient ancestors, today it’s believed that the average American eats 15 to 25 times more omega-6 fats than omega-3s.
Eating more walnuts as part of a healing diet can help close this gap and potentially prevent disease development. For example, walnuts nutrition benefits were praised in the Journal of Alzheimer’s Disease as providing a “significant improvement in memory, learning ability, anxiety, and motor development compared to the control diets without walnuts.”
In addition to omega-3s, walnuts nutrition provides plenty of other noteworthy nutrients too. According to walnut nutrition data published by the USDA, one ounce (approximately 28 grams) of walnuts nutrition, or about 14 halves, has about:
- 185 calories
- 3.9 grams carbohydrates
- 4.3 grams protein
- 18.4 grams fat
- 3.9 grams fiber
- 1 milligram manganese (48 percent DV)
- 0.4 milligram copper (22 percent DV)
- 44.6 milligrams magnesium (11 percent DV)
- 97.8 milligrams phosphorus (10 percent DV)
- 0.2 milligram vitamin B6 (8 percent DV)
- 27.7 micrograms folate (7 percent DV)
- 0.1 milligram thiamine (6 percent DV)
- 0.9 milligram zinc (6 percent DV)
- 0.8 milligram iron (5 percent DV)
In addition, walnuts nutrition contains some vitamin A, vitamin C, vitamin E, vitamin K, niacin, pantothenic acid, choline, betaine, calcium, potassium and selenium.
1. May Help Fight Depression
Omega-3 fats help form the soft, fluid outer lining of cells that gives them the ability to communicate with each other. This is crucial for allowing the movement of “feel-good” neurotransmitters, like dopamine and serotonin, to flow into and out of cells. Without enough of the right kinds of fats in your diet, neurotransmitter function suffers, and many people feel the effects in rising feelings of anxiety, chronic stress, cravings, fatigue and mood swings.
There are compelling population studies linking the consumption of large amounts of omega-3 fats, usually in the form of wild fish in addition to certain nuts like walnuts, to lower rates of depression and psychiatric disorders. Controlled clinical trials researching the effects of omega-3s in depression and heart disease prevention continue to be underway at a number of major research centers. It seems the more we find out about how these special fatty acids work, the more we realize that their benefits are impressive, yet most people are deficient and can’t afford to be.
2. Helps Improve Brain Health and Preserve Memory
Walnuts are considered by many to be a superfood that may help slow aging. Walnut benefits for the brain include supporting memory and thought processing. Many of the same populations that suffer from higher incidences of depression due to a lack in essential omega-3s also fall victim to cognitive decline. This includes age-related conditions like dementia, Alzheimer’s disease and other memory impairments. Recent studies show promising benefits of omega-3 fatty acids in elderly patients at risk not only for cognitive decline, but also for depression.
When researchers from the Department of Biochemistry and Neurology at the University of Karachi in Pakistan evaluated the effects of walnuts on learning and memory in mice, they found significant improvements in learning and memory of walnut-treated mice compared to controls. Mice given walnuts also exhibited a significant decrease in food intake, although this didn’t have negative effects on their normal development. An analysis of their brains showed enhanced neurotransmitter function, protection against damage and improvements in nerves controlling metabolism.
3. Aids Heart Health
There’s a strong connection between both higher nut and omega-3 consumption and improved heart health. According to many studies, walnuts nutrition benefits cardiovascular health by keeping arteries clear, improving circulation, balancing cholesterol levels and lowering disease-causing inflammation.
A recent 2019 study found that replacing saturated fats with walnuts improved blood pressure levels in obese adults with cardiovascular risk. Study participants simply added 2-3 ounces of walnuts to their healthful diet and displayed a reduced risk of heart disease.
Researchers believe that walnut’s fatty acid composition, including its ALA content, fiber and other bioactive compounds, improved the participants’ gut health and therefore positively impacted their heart health. This study contributes to the understanding that changes in gut bacteria can have a significant impact on the health of other major body systems.
A 2018 study found that incorporating walnuts into the diet improved blood lipid profile without adversely affecting body weight or blood pressure.
Another study published in the Journal of the American College of Nutrition in 2012 found that walnut consumption has positive effects on lowering risks for metabolic syndrome, which is a precursor of diabetes and cardiovascular disease. When researchers investigated the effects of 56 grams of daily walnut consumption on endothelial function and other biomarkers of cardiac risk in a population of overweight adults, they found significant improvements in heart health and endothelial function. The patients experienced improved blood flow, better insulin control and healthier blood pressure. Another benefit was that the patients did not gain weight on average despite eating a higher level of high-fat walnuts.
4. Supports the Immune System and May Help Prevent Cancer
Thanks to being a great anti-inflammatory food that contains polyphenol antioxidants, walnuts nutrition benefits immune function and may even help prevent cancer formation. Some research shows walnuts should be part of a diet that helps support cancer treatment.
In 2013, researchers from the University of Texas Health Science Center investigated whether a standard mouse diet supplemented with walnuts reduced the establishment and growth of human prostate cancer cells. They found that the walnut-enriched diet reduced the number of tumors and growth significantly and that the final average tumor size in the walnut-diet animals was roughly one-fourth the average size of the prostate tumors in the mice that ate the control diet.
5. Makes a Filling Snack and Supports Weight Loss
Are walnuts good for weight loss? Yes — despite being a calorie-dense food (as all nuts are), walnuts effectively help alleviate hunger. They are nutrient-dense foods, meaning you consume many essential vitamins, minerals and fats when you eat them — all for a relatively small percentage of your daily calories. Walnuts also have compounds that help burn belly fat, since they’re chock-full of fatty acids and some protein. Both help make you feel full. This is important for curbing food cravings, especially for things like sugar and refined carbohydrates.
Though walnuts are calorie-dense, clinical dietary intervention studies show that walnut consumption doesn’t cause a net gain in body weight when eaten as a replacement food. When you lack fatty acids, protein, fiber or other essential nutrients found in walnuts nutrition, it’s much harder for the body to stay at a steady weight, control blood sugar levels, regulate insulin and appetite, and balance cholesterol.
While sugary snacks can be thought of as metabolism death foods, a one-ounce serving of walnuts, or about a fourth of a cup, eaten between or with meals can help balance blood sugar, improve cognitive function and stop you from overeating later on. Keep in mind that walnuts act like a natural appetite controller, but it might be best to try subbing in walnuts for some other high-fat foods that don’t provide as many benefits — for example, processed lunch meats and vegetable oils.
6. Improves Reproductive Health and Aids in Growth and Development
Walnuts are nutrient-rich in essential minerals. They have protein, fiber, calcium, magnesium, phosphorus, manganese and potassium. Thus, if you have low potassium, for instance, walnuts can bring your levels back up. In fact, all of these are crucial for a developing brain and body, so pregnant women, new mothers and young children (once they’re able to safely tolerate nuts) are all encouraged to enjoy walnuts regularly.
Manganese found in walnuts, in particular, is an important essential mineral for growth, reproductive health, the skeletal system, wound healing and brain development. It’s also needed to maintain a healthy metabolism and to digest and utilize carbohydrates from food that support muscle and tissue growth.
7. Great Way to Increase Children’s Omega-3 Intake
Many health experts recommend giving walnuts to kids as a brain-boosting, nutritious snack. They might also be a natural treatment for ADHD and other developmental problems. Several studies demonstrate greater attention, reduction in behavioral problems and less ADHD-related symptoms in school children when they take omega-3 fat supplements or consume plenty of omega-3s from foods.
Considering it’s hard to get many children to eat wild-caught fish on a regular basis, finding ways to sneak some walnuts into their meals is a great way to give them omega-3s naturally that support their physical and mental health.
Related: Pili Nuts: The Keto-Friendly Nuts that Support the Heart & Bones
Uses in Traditional Medicine
In Traditional Chinese Medicine, walnuts are said to have sweet and warm properties that are associated with winter, the lungs, large intestine and kidney meridians. They are typically eaten raw or added to stir-fries in order to help “tonify the kidneys, nourish the blood, warm the lungs and moisten the intestines.” Walnuts are especially recommended to patients who need help with pain management, digestion, relieving asthma and lowering cholesterol. In order to avoid an upset stomach and diarrhea, it’s typically recommended to avoid eating excessive amounts of walnuts, which can loosen the stools.
According to Ayurvedic medicine, lightly roasted walnuts provide warmth and make a great addition to fruit or warm cereal for breakfast. They are a balanced source of protein, fats and nutrients and have sweet, oily/heavy, slimy and hot properties. This gives walnuts benefits including treating skin conditions and wounds, building strength, improving digestion, building blood, fighting fatigue, and improving respiratory and dental health.
Walnuts vs. Black Walnuts
- There are two common kinds of walnuts: the English walnut, which ironically comes from California, and the black walnut, which is also native to America.
- The two different kinds vary somewhat in terms of their nutritional profile, with the English walnut having slightly less protein and more fat. However, both are still great options.
- Black walnuts (Juglans nigra) have been a nutritious addition to the diets of individuals since ancient times. They contain compounds including flavonoids, quinones and polyphenols and are known for their antineoplastic, anti-inflammatory, antioxidant, antiatherogenic and neuroprotective properties.
- Something that makes black walnut leaves, bark and fruits unique is that this plant contains a constituent called juglone, known to be effective against worms, tobacco mosaic virus and H. pylori. It also has the compound plumbagin, known to have neuroprotective and cancer-fighting effects. Black walnuts also contain other antioxidants, polyphenols and monounsaturated fatty acids, such as gamma-tocopherol, folate, melatonin and phytosterols.
- Common English walnuts are easier to crack and larger than black walnuts. In some places, black walnuts can be purchased in stores or at a reputable online store. The meat encased in the black walnut is much smaller and more difficult to pick out of the shell compared to other walnuts, so it’s common for black walnuts to be chopped when sold.
Related: Walnut Oil Benefits for the Heart, Skin, Gut & More
Walnuts vs. Other Nuts
- Compared to walnuts, almonds are a bit less calorie-dense, higher in protein and lower in fat. They contain more monounsaturated fat and less polyunsaturated fat, including less omega-3s. You can eat 23 almonds for 160 calories, versus 14 walnut halves for 190 calories. Almonds are also a great source of fiber, calcium and vitamin E (the best nut source of this antioxidant).
- Peanuts are one of the highest-protein and fiber nuts, plus one of the lowest in calories, meaning you can eat more of them without consuming loads of calories. However, peanuts can contain mold and are a common allergen, so take precaution when eating them.
- Macadamia nuts are one of the nuts with the most fat and highest amount of calories, although this isn’t a bad thing considering they are very high in monounsaturated fat and healthy saturated fatty acids. Rather than eating lots of peanut butter, try macadamia nut butter as a creamy alternative.
- Brazil nuts are an excellent source of selenium (just one nut contains more than a day’s worth) and contain a good mix of monounsaturated and polyunsaturated fat. Brazil nuts and walnuts contain similar amounts of protein and carbs, but walnuts are a better source of omega-3s.
- Pecans are a high-calorie nut with a high fat content, mostly monounsaturated fat. They contain oleic acid along with phenolic antioxidants. Pecans nut and macadamia nuts overall have the lowest amounts of protein and the highest amounts of fats (but these are still healthy fats).
- Hazelnuts are rich in unsaturated fats (mostly oleic acid) and high in magnesium, calcium, and vitamins B and E.
- When we compare walnut nutrition benefits to benefits of other nuts, we see that walnuts are one of the most nutrient-dense. They have the highest amount of heart-healthy alpha linoleic acid (ALA), a type of omega-3 fatty acid found in plants. However, eating a variety of nuts gives you the most benefits. For example, nuts and seeds, including walnuts, benefit your hair, skin, nails, brain and heart because they all contain healthy fats and slightly different antioxidants and minerals. Many nuts are high in vitamins A, B, and E; folic acid; calcium; magnesium; phosphorus; potassium; and zinc.
- It’s best to avoid nuts packaged or roasted in oil and instead eat them raw or dry-roasted whenever possible.
How This Nut Fits Into a Keto Diet
If you eat a high-fat, low-carb diet — such as the ketogenic diet — walnuts nutrition benefits include supplying you with healthy fats, omega-3s, vitamin E and an array of minerals. Walnuts are also lower in carbs than some other nuts, like almonds, peanuts or cashews.
How many walnuts can you eat in a day if you’re following the keto diet? As a general rule, have no more than a quarter cup of nuts, seeds or nut/seed butters per day when on the keto diet. Even if you’re not following a low-carb diet, this serving size is a good amount to aim for. This provides a good dose of filling fats, as well as some protein and fiber, without too many carbs. How can you use walnuts on the keto diet? Add some to a salad or roasted veggies, try walnut butter in a smoothie, or snack on them raw.
Where to Find and How Use
Walnuts are edible after ripening and being removed from their outer shells. The hard outer shell encloses the walnut, which is really the plant’s kernel or “meat.” A walnut kernel is usually made up of two halves separated by a partition. Ready-t0-eat walnuts are already shelled and removed from their hard coats — which are actually high in nutrients, too, and contain antioxidants.
It’s recommended that you purchase walnuts in their shells and then crack them open yourself just prior to using them. If you can find whole walnuts that haven’t already been de-shelled, stock up on them since they last a while and will be fresher once you do decide to eat them. If not, you can still obtain plenty of benefits from walnuts nutrition by buying shelled whole walnut halves. Just make sure their flesh is white rather than yellow.
Since a yellow flesh can indicate that the walnuts have gone rancid, this will tell you they have lost some of their nutrients. Also keep in mind that organic walnuts tend to have darker brown shells, and their color will vary depending on how much sun the walnut tree branches grew in. Brown coloring on walnuts is not an issue or something to worry about; just avoid yellow spots.
If you’re concerned about the calories in walnuts, how many walnuts should you eat? A typical recommendation is to eat four to six walnut halves per day, although more isn’t necessarily a bad thing if your diet is overall balanced. Aim to have a small “handful,” or roughly a quarter cup — rather than getting carried away with a very large portion size that can cause a stomachache. When should you eat walnuts, morning or night? Anytime that you enjoy them is great, although they tend to be a popular breakfast ingredient in recipes like oatmeal, healthy muffins, etc.
Try the following walnut recipes:
- Raw Walnut Tacos Recipe
- Mango Walnut Spinach Salad Recipe
- Raw Brownie Bites Recipe
- Cheesy Spaghetti Squash Recipe
Risks and Side Effects
Walnuts as Part of a Balanced Diet
To be clear, the type of omega-3 fatty acids found in nuts and seeds like walnuts, chia seeds and flaxseeds is not the same kind of omega-3 found in fish like salmon. Most of the research on omega-3 fats that demonstrate such strong cardiovascular and brain-boosting benefits involve the two omega-3 fats that are found in fish: EPA and DHA.
The kind of omega-3 found in walnuts is called ALA , or alpha-linolenic acid. It’s believed that the body can make the preferred types, EPA and DHA, from the type found in walnuts (ALA), but it can’t necessarily do such a great job of this.
While ALA omega-3 fats from walnuts have plenty of health benefits — and walnuts themselves offer other nutrients, too — it’s wise to get more omega-3s from wild-caught fish and also supplements when necessary. It’s also a good idea to consume all three types of omega-3 fats for optimal benefits, which is why it’s important to vary your diet and eat a variety of different foods.
Keeping Walnuts Fresh and Making Them More Digestible
Walnuts contain a low level of antinutrients, like all nuts. To make them more digestible and get even more benefits from walnuts nutrition, you can soak them overnight, then discard the water. If you’d like, you can also sprout the walnuts, which further increases absorption of their minerals.
Walnuts, like other tree nuts, must be processed and stored properly so they don’t spoil and become rancid. Poor storage in moist and hot places can make the fatty acids in walnuts go bad, leading them to be susceptible to insects and fungal mold infestations. These have the potential to cause growth of aflatoxins, which are carcinogens that shouldn’t be consumed in high amounts. If you ever see mold growing on your walnuts, be careful to throw them out.
- Walnuts (Juglans regia L.) have been providing crucial nutrients to humans for thousands of years.
- Why are walnuts good for you? They come packed with healthy fats, including omega-3s, antioxidants, vitamins and minerals. They are a great source of antioxidants like polyphenols and tannins, as well as fiber, manganese, copper, magnesium and phosphorus.
- Among all nuts, walnuts are the best source of omega-3 polyunsaturated fats. They are low in carbs and a decent source of protein and fiber.
- Health benefits of walnuts include fighting depression, protecting brain health/memory, improving heart health, supporting the immune system, improving reproductive health and supplying omega-3s to children.
Read Next: Cashews Nutrition: Helps Prevent Cancer, Diabetes & More