How Much Protein Does the Body Need Daily?

Protein is an essential nutrient, forming one of the body's building blocks. It contributes to cell building and repair and supports growth and development throughout life.

Daily protein requirements vary depending on age, sex, activity level, and health status. However, most adults are advised to obtain between 10% and 35% of their total daily calories from protein.

Daily Protein Requirements

The U.S. Department of Agriculture (USDA) publishes dietary guidelines for Americans every five years. The 2026 recommendations indicate that adults should aim to consume between 1.2 and 1.6 grams of protein per kilogram of body weight, nearly double the previous recommendation of 0.8 grams/kg.

The updated guidelines focus on a broader range of macronutrients, primarily protein, to support "nutritional adequacy," compared to previous guidelines that focused primarily on minimum intake to avoid nutrient deficiencies.

Factors Affecting Protein Needs

Physical characteristics and lifestyle influence the amount of protein the body needs. Some of the most important factors include:

Physical activity: Physically active people may need more protein to build and maintain muscle.

Age: Older adults need adequate protein to help slow age-related muscle loss.

Health goals: High-protein diets may help with weight loss or maintenance.

Medical conditions: Certain conditions, such as chronic kidney disease, may require reduced protein intake.

Pregnancy: Nutritional needs, including protein, increase during pregnancy.

What Happens When You're Deficient in Protein?

Most people in the United States consume adequate amounts of protein, including those who follow vegetarian or vegan diets. However, food insecurity can lead to protein deficiency, and older adults are more susceptible as their protein needs increase with age.

Signs of protein deficiency include:

Hair, skin, and nail problems.

Increased appetite.

Higher risk of infections.

Mood swings.

Muscle weakness.