NAIL BITING is caused by mineral deficiencies or severe mineral imbalance. A person eats finger and/or toenails, instinctively, to recycle minerals in the nails. Eating any or all of the following usually corrects this mineral deficiency within 3 months: no-salt-added raw cheeses with an equal quantity of fat, especially unsalted raw butter, fresh raw ocean fish (including scallops, oysters or clams), whole raw milk, and, occasionally, ¼ teaspoon of clay. See Clay, page 181.