There are specific amounts of calories needed to support metabolic activity in a day. There are also suggested amounts of calories needed per pound for the body to function at optimum level.
Finding the Minimum Amount of Calories
There is a formula to find the necessary amount of calories needed for your body weight to support metabolic activity for the day, according to the University of Arizona. Take your body weight in pounds and multiply by 10. The result is the minimum calories needed to sustain your weight. For example, a 190-pound person needs approximately 1,900 calories to maintain metabolic activity and weight. You consume 10 calories per pound a day.
Finding Additional Calories
You must also apply your physical activity throughout the day to accommodate for additional calorie intake if your goal is to maintain your weight. You will need to rate your exertion level on a scale of 1 to 10. When you choose your exertion number, multiply that by your body weight. That will be the additional calories needed to sustain your weight. For example, a 190-pound person chose 7 on the exertion scale. That would be an additional 1,330 calories and put him at 17 calories per pound a day.
Suggested Protein, Carb and Fat Intake
There are suggested grams per pound for nutrient intake. Protein should be 0.36 to 0.68 g per pound for nonathletes. Carbohydrates should be 50 percent to 60 percent of your dietary intake for nonathletes. Fats should be less than 25 percent. If you are an athlete, consume higher amounts of protein and carbohydrates. There also is a formula to find minimum calories per pound for proteins and carbs. For protein: 0.36 x body weight in pounds x 4 calories. For carbohydrates: body weight in pounds x 10 x 0.5 x 4 calories.