By varying what you eat, you protect your health in two ways. First, you ensure that you get all the nutrients you need. If you eat the same foods day after day, you are more likely to shortchange yourself of some needed vitamins, minerals, or other elements. You don't have to memorize the government's recommended daily allowances of carbohydrates, fat, protein, and vitamins -- just go for variety. The second reason you should vary your diet is to avoid eating too much of anything that is not good for you. Surprisingly, there are many toxins, both natural and man-made, in the food we eat. For instance, celery, basil, white mushrooms, peanuts, and alfalfa sprouts all contain natural toxins that shouldn't be eaten every day or in large quantities.