There is no recommended number of servings from the tip of the pyramid - fats, sweets and alcohol. Use these foods sparingly. By eating a variety of foods, you are less likely to develop either a deficiency or an excess of any single nutrient. Variety also reduces your likelihood of being exposed to excessive amounts of toxins that are found naturally in many foods. If you are too fat, your chances of developing some chronic disorders are increased.
Obesity is associated with high blood pressure, heart disease, diabetes, and some types of cancer.
If you are too thin, you are at greater risk of early death and, for women, developing osteoporosis. Thus, you should try to reach and maintain a healthy weight. There is no exact answer right now. Whether your weight is healthy depends on how much of your weight is fat, where the fat is located, and whether you have weight-related medical problems such as high blood pressure. However, most adults at healthy weight fall within a range of weights for their age and height.