Celery is used in weight-loss diets, where it provides low-calorie dietary fibre bulk. Celery is often incorrectly purported to be a "negative calorie food" based on the idea that the body will burn more calories during the digestion of the food than the body can extract from the food itself. However, the fact that the body uses very small amounts of energy in digestion compared to what can be extracted even from a low-calorie food like celery disproves this hypothesis.

Celery is used in weight-loss diets, where it provides low-calorie dietary fibre bulk. Celery is often incorrectly purported to be a "negative calorie food" based on the idea that the body will burn more calories during the digestion of the food than the body can extract from the food itself. However, the fact that the body uses very small amounts of energy in digestion compared to what can be extracted even from a low-calorie food like celery disproves this hypothesis.