Protein plays more roles in your body than any of the other macronutrients. It’s responsible for cell growth and repair, allows your immune system to fight off infection and acts as a precursor for several hormones. Your body can also call on protein for energy. You have to eat enough protein to meet your needs to keep your body processes running smoothly. You can calculate your protein needs two ways.
How Much You Eat
The first, and more general way, to calculate protein needs is based on how many calories you eat. The current recommendation is that 10 to 35 percent of your calories should come from protein. If you follow the standard 2,000-calorie diet, you should consume 200 to 700 calories worth, or 50 to 175 grams, of protein per day.
How Much You Weigh
Another, more specific, way to calculate your protein needs is based on body weight. The current recommendation is to consume 0.8 grams of protein for every kilogram, or 2.2 pounds, of body weight. Using this formula, a 150-pound person would need approximately 55 grams of protein, while a 120-pound person would need 44 grams.