NIH Healthy Diet Calculate your body mass index (BMI). Determine your energy (calories) and vitamin requirements.

Food and Nutrition Information Center: A United States Department of Agriculture Site

National Heart, Lung, and Blood Institute Guidelines for Weight: Obesity is second only to smoking as the largest cause of preventable death in the United States. The site also contains a program to calculate your body-mass index (kg/meter2), or BMI, where one is considered overweight if this value is 25. Alternatively, the BMI can be calculated by multiplying the weight in pounds by 703, and dividing by the height in inches squared. A person 5 ft 7 inches (67 inches) who weighs 159 pounds has a BMI of 24.9.

Recommended Daily Allowances (RDA) of Nutrients: Data formulated by the National Academy of Science of the United States

United States Department of Agriculture (USDA) Nutrition Data: Data on the biochemical composition of more than 5000 foods including energy (calories), protein, fats including cholesterol, carbohydrate, fatty acid composition, and amino acid composition.