The nutritional value of nuts can be measured not only in terms of what vitamins, minerals, proteins, and fats they contain, but also in terms of what they don't contain. A serving of unsalted nuts, while being fatty-rich and a source of several essential minerals and vitamins, contains no cholesterol and only trace amounts of sodium. The United States Food and Drug Administration (FDA) allows packages of nuts to be labeled with wording that advises that they may also reduce the risk of heart disease because of the monounsaturated fats that nuts contain help to lower blood cholesterol. Besides this, the main nutritional value of nuts is in the protein, vitamins, and minerals that they provide.
Protein is an essential part of the nutritional value of nuts because a certain amount of it is necessary for a healthy body, but the protein in nuts also creates a feeling of fullness that can lead to weight loss. Eating nuts as a part of a healthy diet reduces the craving for more fattening foods. A peanut, although technically a legume rather a nut, contains the most protein of any nut, with a 1 oz (28 g) serving containing about 7 grams (0.25 oz) of protein. The next most protein-rich nuts are almonds and pistachios, while those with the least amount of protein are macadamias.
Further contributing to the nutritional value of nuts are a host of minerals occurring in different combinations and concentrations. The minerals in nuts include magnesium, manganese, zinc, and iron, as well as many others. A 1 oz (28 g) serving of hazelnuts provides close the daily dose of manganese recommended by the FDA, while the same size serving of pine nuts exceeds the recommended dose. Manganese helps the body assimilate vitamin C and is important for bone growth. Almonds, Brazil nuts, and cashews are good sources of magnesium, which is necessary for proper muscle function and energy metabolism.
Being a good source of vitamins contributes to the nutritional value of nuts not only because vitamins are essential for cell metabolism and growth, but also because vitamins help to prevent disease. While the vitamins in nuts do not include vitamin A, C, or D, they do include many from the B-complex spectrum and vitamin E. Almonds are the best source of vitamin E, and a 1 oz (28 g) serving provides 35% of the daily recommended dose by the FDA. The same amount of peanuts gives 10% of the recommended dose of folate, a B-vitamin that lowers the risk of heart disease.