Time and again one hears about special foods for weight loss. However, the search for a magic bullet for weight loss has found some foods that carry negative calories — implying that they have no calories.
It is believed that one can lose weight by eating these negative calorie foods as they supposedly take more energy to process and digest than they provide in calories. For example, one will burn about 60 calories digesting a 15-calorie piece of celery, with a loss of 45 calories. This is because it is predominantly composed of water and un-digestible fibre in the form of cellulose. Other examples include cabbage, cauliflower, broccoli, berries, turnip, radish, asparagus, grapefruit, cucumber, lettuce and spinach.
The fact is that about 10 per cent of a meal’s energy value is used up in digestion and storage of nutrients in the food we eat. This happens when the metabolism is stepped up in roughly five hours after finishing a meal. Hence, low calorie foods require large amount of energy to digest compared with the amount of calories they provide. However, they are not zero calorie foods.
All foods have some calories. No food is actually “negative calorie” food. But the overall effect of certain foods in our body is that of “negative calories”.
This means, while it is possible to have a negative calorie food, these are not zero calories and there are no reputable scientific studies to prove that certain foods are negative calories or they aid in weight loss. Fruits and vegetables in general can help in weight loss, if they are included as part of a healthy diet and lifestyle.
Including 5-9 servings of foods with negative calories in your daily diet is recommended. But, following extreme diets and choosing foods on the basis of negative calories can cause imbalance and nutrient deficiencies.
The only thing which is zero calories is water. Zero calories beverages do take more than zero calories to process within the body, however they do not offer the dietary sustenance that other “negative calorie” foods do in the form of fibre, carbohydrates, vitamins, and as such, are not generally regarded as being negative calorie. However, negative calorie foods help to lose calories and fuel a positive start to a permanent weight loss programme.
Combining negative calorie foods with other food groups such as whole grains, pulses, low fat dairy and lean protein like soy, nuts and seeds can go a