A calorie is a calorie, so they say. It shouldn’t matter whether it comes from steak, a carrot or a doughnut. Except it does! Our body works harder to extract calories from some food compared to others, which is why calories don’t count. Remember, we eat food, not calories.
Dr Giles Yeo MBE (Wolfson 1994) explains why calories don’t count and why instead we should be focusing on the food we eat.