explain why 1 Calorie from fat is not the same as 1 Calorie from carbs/sugar as far as our bodies are concerned. Our bodies use sugar more efficiently.
As you probably know, the scientific definition of a calorie is the amount of energy needed to raise 1 gram of water 1 degree celsius. This is measured by burning the food and measuring the change in temperature of the water. By this test, fiber will also have calories, but we know fiber has little to no caloric value to our bodies as it is not broken down and absorbed.
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