The total calories in food depend on the amount of carbohydrates, fat and protein in that food. Brand name foods typically provide this information on nutritional labels, but you may need to calculate calorie content for generic or bulk foods. You should frequently calculate the total calories in your food as part of your diet program. Many diets restrict the amount of protein, carbohydrates or fat that you can consume.
Step 1
Obtain the number of grams of carbohydrates, fat and protein in the food. You can get this information from the nutritional label or a nutritional database such as the Nutrient Data Laboratory from the United States Department of Agriculture. Assume for this example that the food contains 3 g of carbohydrates, 6 g of fat and 7 g of protein.
Step 2
Calculate the calories in the food that come from carbohydrates. Carbohydrates contain about four calories per gram, so you multiply the number of grams of carbohydrates by four. The food in this example contains 3 g of carbohydrates; thus 3 x 4 = 12 carbohydrate calories in the food.
Step 3
Compute the number of calories in the food that comes from fat. Fat contains about 9 calories per gram, so you multiply the number of grams of fat by nine. The food in this example contains 6 g of fat; 6 x 9 = 54 fat calories.
Step 4
Derive the amount of calories in the food that comes from protein. Protein contains about 4 calories per gram, so you multiply the number of grams of protein by four. The food in this example contains 7 g of protein; 7 x 4 = 28 protein calories in the food.
Step 5
Calculate the total number of calories in the food from carbohydrates, fat and protein. The food in this example contains 12 calories from carbohydrates, 54 calories from fat and 28 calories from protein. The total number of calories in this food is 12 + 54 + 28 = 94 calories.
Things You'll Need
- Nutritional label
- Calculator
Member Comments