Dietary macronutrients include carbohydrate, protein and fat. Each macronutrient provides a specific amount of calories per gram. Understanding the amount of calories in 1 g of carbohydrate allows you to make informed dietary choices.
According to the book “Anatomy and Physiology” by Kenneth Saladin, carbohydrates are stored in blood, liver and muscle tissue and used for energy during physical activity. In addition, carbohydrate is the preferred energy source for red blood cells and the brain during rest.
Not all carbohydrates are created equal. Complex carbohydrates such as whole-grain bread provide more nutrients than simple carbohydrates such as white rice. Fiber from complex carbohydrates supports healthy digestive system function.
One g of carbohydrate or protein contains 4 calories while 1 g of fat provides 9 calories. One large white bagel contains 70 g of carbohydrate while one cup of brown rice contains 45 g.