Walnuts and cashews, both tree nuts commonly used in baking and on snack trays, are rich in nutrients and cholesterol-free. A half-cup of halved walnuts has 327 calories. Cashews are a little more energy-dense, with 393 calories, but they also have 10.5 grams of protein, compared to the walnuts' 7.5 grams. Walnuts are higher in fiber, providing 3.4 grams, more than a gram greater than the fiber in cashews. Your health goals should determine whether walnuts or cashews are a better choice for you.
Eaten in moderation, either type of nut makes a nutritious snack that can help keep your heart healthy, but walnuts may be a little better. Each type of nut has about 32 grams of fat, but cashews have twice as much saturated fat, with 6 grams, while walnuts have only 3 grams of saturated fat. The remaining lipids are from healthy monounsaturated and polyunsaturated fatty acids, including alpha-linolenic, linoleic and oleic acids, which may help keep your triglycerides and LDL cholesterol low. Cashews are also higher in sodium, with 11 milligrams per half-cup, while walnuts have 1 milligram of sodium.
Walnuts and cashews are not rich in vitamins, but a half-cup of cashews provides 24 micrograms, one-fourth of your daily requirement, of vitamin K, a nutrient that plays a role in bone health and helps your blood clot properly. Walnuts only have 1.4 micrograms of vitamin K. Walnuts are higher in vitamin B-6, however, benefiting your metabolism of fats, protein and carbohydrates. Each half-cup of walnuts gives you one-fifth of the B-6 you need daily, while cashews provide one-eighth. Each has about 12 percent of the folate you need each day and small amounts of thiamin, riboflavin, niacin and vitamin E, but cashews are a bit higher than walnuts in each of those nutrients.
Cashews tower over walnuts in terms of mineral content. A half-cup of cashews has about 55 percent of the magnesium and phosphorus you need daily, while walnuts offer 25 percent. Cashews provide half the zinc and one-fourth of the iron you need daily, and walnuts provide one-fifth and 8 percent, respectively. Although cashews and walnuts are both rich sources of minerals, you get twice as much nutrition per half-cup from cashews. Each type of nut also has about 6 percent of your daily requirement for calcium and potassium.
Walnuts may be preferable to cashews if you are trying to lose weight or maintain your current weight. Each 100 milligrams of walnuts has 2.71 milligrams of cyanidin, an antioxidant plant pigment that may play a role in preventing obesity, according to researchers who published a study in "The Journal of Nutrition" in 2003. They found that mice that followed high-fat diets lost a significant amount of weight when they took in 2 grams of cyanidin per 100 grams of food. The researchers concluded that cyanidin-rich foods may help prevent obesity and diabetes. Cashews do not contain any cyanidin.
Maia Appleby is a NASM-certified personal trainer with more than 15 years of experience in the fitness industry. Her articles have been published in a wide variety of print magazines and online publications, including the Gale Encyclopedia of Nursing and Allied Health, New Moon Network and Bodybuilding.com.