Q. How much weight will I gain eating 500 extra calories?

A. The direct (text book) answer is that if you eat 500 extra calories in a day, that days caloric excess will result in a weight gain of 2.3 ounces. It takes 3,500 calories consumed in excess of caloric homeostasis to gain 1 lb. of fat. Caloric homeostasis refers to the number of calories your body needs to “break even” meaning it doesn’t lose or gain weight at that number. The number of calories that your body uses each day at total rest (resting metabolic rate) plus the calories your body uses during voluntary activity throughout the day are added together to determine that day’s caloric expenditure. If you eat an excess of 500 calories every day for 7 consecutive days, you should gain a pound of fat in a week. Let me assure you that it isn’t always that simple depending on a variety of potential metabolic factors. Take into consideration the composition of the weight gained. It could be all fat or a combination of fat and muscle depending on activity levels and whether a strength training regimen is simultaneously utilized. Remember food is fuel, and food quality plays a tremendous role in supporting a healthy metabolism.

Wayne Coolidge Jr., M.Ed., CHES is a scholar-practitioner, author, and speaker. He owns Healthy Dynamic Living, an innovative health promotion consulting firm.