A review of the fundamentals of diet.

Dietary recommendations should be individualized for each patient, but certain basic principles apply to most people. A healthful diet should include a wide variety of whole, unprocessed foods that are free of additives and, if possible, grown without the use of pesticides, herbicides, and other potentially toxic agricultural chemicals. For people who do not have specific food intolerances, such a diet generally includes liberal amounts of fresh fruits and vegetables, whole grains, nuts, seeds, and legumes. For most people, animal foods such as eggs, fish, chicken, beef, and dairy products can be healthfully consumed in moderation. It is not necessary to consume animal foods to maintain good health. In fact, compared with omnivores, vegetarians have a lower risk of developing a number of chronic diseases. However, vegetarians must carefully plan their diet so as not to develop nutritional deficiencies.