Nutritional Requirements

ByShilpa N Bhupathiraju, PhD, Harvard Medical School and Brigham and Women's Hospital;
Frank Hu, MD, MPH, PhD, Harvard T.H. Chan School of Public Health
Reviewed/Revised Feb 2023

General guidelines for a healthy diet have been developed even though daily nutritional requirements, including those for essential nutrients, vary depending on age, sex, height, weight, physical activity, and the rate at which the body burns calories (metabolic rate). Recommended dietary allowances for protein, vitamins, and minerals are periodically published by The Food and Nutrition Board of the National Academy of Sciences–National Research Council and the U.S. Department of Agriculture. These allowances are intended to meet the needs of healthy people.

The U.S. Department of Agriculture also publishes MyPlate, a web site that helps people develop a healthy eating style and make healthy food choices that suit their individual needs.

In general, authorities recommend that people

  • Follow a healthy dietary pattern at every life stage

  • Customize and enjoy nutrient-dense food and beverage choices to reflect personal preferences, cultural tradition, and budgetary considerations

  • Focus on meeting food-group needs with nutrient-dense foods and beverages, and stay within calorie limits

  • Limit foods and beverages higher in added sugars, saturated fat, and sodium, and limit alcoholic beverages

Adequate fluid intake is also important.

Eliminating trans fats from the diet is recommended. When possible, monounsaturated fats and polyunsaturated fats, including the polyunsaturated fats called omega-3 fats, should be substituted for saturated fats and trans fats.

More Information

The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

  1. Dietary Guidelines for Americans 2020-2025: U.S. Department of Agriculture (USDA) and U.S. Department of Health and Human Services nutrition recommendations by life stage, from birth through older adulthood

  2. MyPlate Plan: USDA's food guidance system promoting a healthy eating routine with a variety of fruits, vegetables, grains, protein foods, and dairy and fortified soy alternatives

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