Peanuts. The most peculiar of the nuts, and the most common in our culture, peanuts are not in fact a true nut but a legume or pea (thus ?peanuts?), which grows on a small bush that yields small, soft, fibrous shells each containing usually two or three ?nuts.? Peanuts, or ?goobers,? grow commonly in the southern United States but are now grown largely in China and India, where their oil is used widely in cooking. Peanuts are also called ?monkey nuts? because monkeys love them, as do little human monkeys, especially as peanut butter here in the United States. In poorer, more populated countries, such as China, India, and Africa, peanuts are used in the daily diet in many vegetarian dishes, to which they add more complete proteins.

Peanuts probably have as good an amino acid balance as any vegetable food. They are about 25 percent protein and very rich in nutrients. Their fat content is about 50 percent of the nut, and three-fourths of it is unsaturated. The B vitamin content of peanuts is better than that of most nuts, probably because they are a bean. Niacin and biotin are best, but all B vitamins are represented except B12. Potassium, magnesium, and phosphorus are highest of the minerals, while calcium, iron, zinc, copper, and manganese are also found in substantial amounts.

Stored peanuts may easily become moldy, a concern especially for those sensitive to molds. Peanuts have been known to become contaminated with molds containing aflatoxin, a substance that is thought to be carcinogenic. Also of concern is that much of the peanut butter consumed in this country is the processed variety, with not only the high fat and oil content of peanuts but additional hydrogenated fats, which are more toxic in the body. (See discussion of hydrogenated oils in Chapter 4, Lipids , and in the next section, Oils .) More additives?salt, sugar, dextrose, and others?make this manufactured peanut butter a poor quality food. Many companies now use ground peanuts only to make their butters; better yet, some stores have nut grinders where we can make our peanut butter right on the spot. It is best to refrigerate shelled peanuts and peanut butter to avoid rancidity.

Many people eat roasted and salted peanuts more than the fresh variety. Though a mild roasting of the peanut may make it a little easier to digest and not lower the nutrient value too much, the extra salt is not really needed. Some people do not do well on peanuts at all. Digestive problems, gallbladder irritation, or just plain allergy to these nuts are possible. Overall, they are still the most popular American nut and a good-quality food.

Pecans. Pecans are nuts for a special treat, such as for holiDay s or in the traditional pecan pie, usually sweetened with maple syrup. Pecans (and macadamias), however, contain the lowest protein (about 10 percent) and highest fat (over 70 percent) of all the nuts. They grow on large trees often taller than 100 feet; the nuts are about four to a pecan fruit, each nut protected by a hard, woodlike shell. In fact, pecan shells can be ground and used as wood sculpture material (I have a pecan shell lion in my collection).

Pecans contain some vitamins A, E, and C, niacin, and other B vitamins. They are low in sodium and high in most other minerals, including zinc, iron, potassium, selenium, and magnesium. Copper, calcium, and manganese are present in fairly good amounts as well.

Pistachios. Pistachios are those sweet and flavorful nuts of which it is ?hard to eat just one.? The pistachio nut or fruit grows on a small tree usually about 10?15 feet high and is very popular in the Mediterranean and middle Eastern countries. It is most commonly eaten in the shell but is also used in cooking, in making sauces, as flavoring in baking cakes, and in ice creams. It is best to avoid the less healthy salted and red-dyed pistachio nut and go with the natural variety.