Content

• Steps
• Method 1 of 3: Convert grams of fat to calories
• Method 2 of 3: Convert grams of carbohydrates and protein to calories
• Method 3 of 3: Understand the Difference Between Grams and Calories

Knowing how to count calories is a great way to learn how to eat right. While most food packages list the number of calories they contain, they often don't say what specific nutrients those calories come from. By understanding the difference between calories and grams and learning the conversion factor, you can easily figure out how many calories are in certain nutrients.

Steps

Method 1 of 3: Convert grams of fat to calories

1. 1 Look at the nutrient label. Most labels will tell you how many grams of fat are in each serving of a particular food. This will help you calculate the calories.
2. 2 Multiply grams of fat by 9. One gram of fat contains 9 calories. To find out how many calories are from fat, simply multiply grams of fat by 9.
   • For example, if a food contains 10 grams of fat, you would multiply by nine calories for a total of 90 calories. This is the number of calories that corresponds to a given grams of fat.
3. 3 Count how many calories are in the whole food. To find out the total number of calories in the fat content of a food, multiply the original number you received earlier by the number of servings indicated on the label.
   • If the label says three servings, multiply 90 by three to get 270 calories.

Method 2 of 3: Convert grams of carbohydrates and protein to calories

1. 1 Carbohydrates are organic compounds. They are composed of carbon, hydrogen and oxygen. Carbohydrates always contain calories (4 per gram), however, this does not mean that all where there are calories is carbohydrate. Calories are found in other macronutrients as well.
2. 2 Examine the nutrient label. You will see how many grams of carbs are in one serving. Carbohydrates contain 4 calories per gram. Multiply your carbs by 4 to find out how many calories they contain.
   • For example, if a food contains 9 grams of carbohydrates, calculate (9 x 4) to get 36 calories. The number 4 is used as a multiplier because there are 4 calories in each gram of carbohydrate.
3. 3 Find out how many calories are coming from protein. Proteins are also listed in grams on the product label. Just like carbohydrates, there are 4 calories per gram of protein. Multiply your grams of protein by 4 again to get your calories.

Method 3 of 3: Understand the Difference Between Grams and Calories

1. 1 Understand the difference between grams and calories. A gram is a metric unit of weight equal to one thousandth of a kilogram. A calorie is a unit of energy that people get from food. About 450 grams of body fat equals approximately 3,500 calories.
   • Gram and calorie are different units of measurement that cannot be converted to one another.
2. 2 Find out which energy source you want to measure your calories for. The number of calories per gram of food depends on the ratio of macronutrients in it. The human body can obtain energy (use calories) from three main macronutrients: proteins, fats and carbohydrates.
   • You cannot weigh food and convert grams to calories. You need to know how many calories there are in each individual gram of macronutrients in order to calculate your total calories.
3. 3 Multiply the number of grams by the number of conversion. Look at the label of the product for which you want to calculate the calories. Each nutrient will be listed in grams. Once you find what you need, multiply that number by the number of calories in each gram of that particular nutrient. ...