Protein
Definition
One of the three macronutrients providing 4 calories per gram, essential for building and repairing muscles, tissues, enzymes, and hormones.
Protein is a macronutrient made up of amino acids, which are the building blocks of muscle, bone, skin, hair, enzymes, and hormones. Nine essential amino acids must come from food, as the body cannot produce them. Complete protein sources containing all essential amino acids include meat, fish, eggs, dairy, soy, and quinoa.
Protein needs vary by activity level and goals. Sedentary adults need about 0.36 grams per pound of body weight. Active individuals and those building muscle should aim for 0.7-1 gram per pound. Athletes in heavy training may benefit from up to 1.2 grams per pound.
Protein has the highest thermic effect of food among macronutrients, meaning your body burns more calories digesting protein than carbs or fat. It also promotes satiety, making it valuable for weight management. Distributing protein intake evenly across meals (25-40 grams per meal) optimizes muscle protein synthesis throughout the day.
Related Calculators
Related Terms
Macronutrients
healthThe three categories of nutrients that provide calories and energy: protein, carbohydrates, and fat, needed by the body in large quantities.
Lean Body Mass (LBM)
healthThe total weight of your body minus all fat weight, including muscles, bones, organs, water, and other non-fat tissues.
Calorie
healthA unit of energy used to measure the energy content of food and beverages and the energy expenditure of physical activities.
Carbohydrate
healthOne of the three macronutrients, providing 4 calories per gram, serving as the body's primary and preferred source of energy.
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