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Major Nutrients in Food

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Topic Overview

The major nutrients-protein, carbohydrate, and fat-provide the body with energy. This energy keeps your heart beating, your brain active, and your muscles working. The energy is measured in calories.

Nutrients in foods
Nutrient Function Some sources
Protein has 4 calories per gram Provides energy; builds and repairs body cells; part of various enzymes, hormones, and antibodiesMeat, poultry, fish, eggs, beans, milk and milk products, grains, seeds and nuts
Carbohydrate has 4 calories per gram Provides energy needed by the brain, nervous system, and red blood cellsBreads, cereal grains, pasta, rice, fruit, starchy vegetables, milk, sugar
Fat has 9 calories per gram Provides energy; carries fat-soluble nutrients (vitamins); part of cell membranes, membranes around nerves, hormones, bile (for fat digestion)

Meat and poultry, some fish, milk and milk products that are not fat-free, nuts and seeds, oils, butter, margarine, salad dressing, some candy, some desserts


WebMD Medical Reference from Healthwise

Last Updated: November 14, 2014
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.
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