Protein is needed for nearly every function in the human body and is essential for building and maintaining muscle mass. High-protein foods include meat, poultry, seafood, soy products, seitan, eggs, dairy foods, legumes, seeds, and nuts. The amount of protein you require per kilogram of body weight depends on your age and activity level. To convert pounds of body weight to kilograms, divide by 2.2. For example, a 150-pound adult weighs 68 kilograms.
