Question: When is a calorie a calorie
Answer: When it is in a lab.
To calculate how many calories are in a certain food, the food is dried and burned in a lab. The resulting heat from the burning of the food is measured in a calorimeter to obtain the number of calories in the food. That number is included on food labels, and we assume that 140 calories in the lab are 140 calories in our bodies. It does not work that way.
Let’s take two different foods containing 140 calories and evaluate them. I picked 140 for a reason—it is the number of calories in a 12 ounce can of Coke. When you drink a can of Coke, your body absorbs almost every one of those 140 calories the lab found. Let us then take 140 calories of sugar snap peas, which is about 5 cups. There are approximately 8 grams of fiber in the sugar snap peas. That fiber surrounds the sugars, slows the absorption of the sugars and some of those calories (about 15%) will pass through your system. Each of the calories in sugar snap peas is then about 0.85 calories. In this case, 140 calories of snap peas is essentially 119 calories (140 x 0.85 = 119) in our bodies.
Can you imagine eating 5 cups of snow peas? And most servings of Coke are much larger than 12 ounces.