Below are some general guidelines that apply to everyone and are important for good health.
Because there is such strong evidence linking obesity to many chronic or acute diseases, the World Health Organization and the U.S. Department of Health and Human Services recommend that you aim for a healthy body weight with a body mass index (BMI) between 18.5 and 25. BMI indicates an individual's weight status in relation to height. It doesn't apply to children, the elderly, or the very athletic. Calculate your BMI with this tool from the National Heart, Lung, and Blood Institute .
Studies show that diet alone is not as effective in achieving a healthy body weight as diet combined with exercise. Physical activity has many other health benefits as well. See the Fitness and Exercise section  for recommendations on how to be physically active each day. Even relatively small weight loss can make a difference in health. Losing just ten pounds reduces blood pressure, improves glucose tolerance, and improves blood lipids.
Whether you need to lose or maintain weight, you should make healthy food choices following the Dietary Guidelines for Americans , developed by the U.S. Department of Health and Human Services and the U.S. Department of Agriculture. These guidelines will improve your health, help you meet your nutrient requirements, and reduce your risk of chronic disease.
To stay within that number and get the nutrients you need to perform well, maintain wellness, and fight disease, you cannot eat too many high-calorie items. However, some age groups or people with specific conditions have special nutritional needs .
To simplify healthy eating, the U.S. Department of Agriculture has replaced the traditional food pyramid with the Choose My Plate  graphic . We recommend the Harvard School of Public Health version, called the Healthy Eating Plate, which points consumers to the healthiest choices in the major food groups based on the best scientific evidence.
Although it is not formally part of the dietary guidelines, it is commonly realized that it is important to drink 8 to 10 glasses of water a day to help your body's biological processes, especially carrying nutrients to cells and eliminating wastes. It is best to drink purified water, so investigate getting a water purifier for your home if you don't already have one.
The Institute of Medicine (IOM) advises men to consume roughly 3.0 liters (about 13 cups) of water a day and women to consume 2.2 liters (about 9 cups) of water a day.
Eighty percent of this should come from drinking water and other beverages, (but not soda, coffee, or alcohol). The remaining 20% should come from foods-especially fruits and vegetables, which are 70% to 95% water.
Your water needs depend on many factors, including your health, how active you are, and where you live. It's generally not a good idea to use thirst alone as a guide for when to drink. By the time you become thirsty, you may already be slightly dehydrated. It is especially important for older adults to drink water before they become thirsty, because your thirst sense is diminished as you get older.
How, when, and where do you eat? If you're like many Americans, you may often eat while doing something else: driving, talking on the phone, watching television, or reading. In short, you may pay little attention to your food.
As a result:
Learn about being why being mindful while eating matters .
Eat with Others
Apart from the biological effects of eating on the run, there are social, psychological, and spiritual effects. Fast food habits can deny you the benefits gained from preparing foods with mindfulness, appreciation, and love, and eating with others in a loving and relaxing atmosphere.
Research demonstrates that the social component to eating is critically important to health outcomes and wellbeing. In a recent study of adolescents, researchers found that frequent family meals were not only related to better nutritional intake, but also decreased risk for substance abuse, sexual intercourse, depression, eating disorders, and poor academic performance. Family mealtimes are a strong protective factor in the lives of adolescents. It stands to reason that eating with others you care about is beneficial to everyone.