All foods contain a certain amount of calories because this is the basic meaning of “food”: they satisfy our daily energy needs.
But nowadays we have an increasing concern of intaking “too much energy”. And the food companies have thoughtfully developed a series of “0-calorie food,” which claim that they do not have calories themselves and will not gain weight after we eat them.
But can the calorie amount of food be “negative”? It just sounds unbelievable, which means such food will not only “produce 0 calories” when we eat them, but will also “consume calories”. That is negative-calories food.
In other words, the more you eat, the thinner you become! Is that magic?
Do Negative-Calorie Foods Exist?
Actually, this kind of magic food is theoretically feasible. So what’s going on here?
It turns out that when we do the math of calories, we often leave out one key factor: the body uses energy when digesting and absorbing food!
The energy consumed by the body in digesting and absorbing food is called the specific dynamic action of food. If you feel hot after eating, it is to some extent the contribution of the thermal effect of food, that your body is paying for the energy while digesting food and eventually this energy turned into heat.
The thermal effect of food has to do with many factors. For example, the thermal effect varies by food type. Protein has the highest thermic effect, with 25% – 35% of energy converted into heat when digesting protein; fats and sugars are a bit lower, at about 5% – 15%.
Of course, this is only the average of the population. If it is specific to a person, the data may vary widely. Some people have a high thermic effect on food no matter what they eat, and some people keep it low.
If there is a food that has a thermic effect of more than 100%, then when we eat that food, our body produces more heat from the digestion process than the food itself has energy.
For a simple example, if we eat 100 calories of sugar, and our body consumes 10 calories to digest the sugar, the caloric effect of the sugar is 10%.
We eat 100 calories of food X. In order to digest food X, our body actually consumes 150 calories, so the thermic effect of food X is 150%.
At this point, food X becomes a “negative-calorie food”. When we eat it, instead of producing energy, it consumes energy. The more you eat, the more energy you consume.
If you check the Internet, you will find that there are many foods that are claimed to be “negative-calorie food”. The most common ones are, for example, celery, apples, spinach, and so on. Some people also claim that dairy products and oats are calorie-negative.
But the hard truth is that none of the common fruits, vegetables, dairy products, and grains have a food caloric effect of more than 30%. Celery, for example, has a food caloric effect of only about 15% on average. In other words, it does not take much effort to digest these foods.
Think about this, if the caloric effect of these foods can exceed 100%, which means people pay extra energy to eat and digest these common foods, then how do humans last until today?
So, is it true that “negative-calorie foods” do not exist?
I can’t say so. Because it is easy to think of a food that meets the requirements, that is, the ice water.
Ice water itself does not carry any calories and has 0 calories, but the body has to consume some calories in order to warm it up to body temperature – so its calories should be negative. Perfectly fits the theory.
But it doesn’t really help that drinking an entire glass of ice water burns only 2 kcal of energy. If you want to lose weight with this, you need to drink at least 100 cups of ice water a day to do so.
If you really drank that much, then you should have been in the hospital intensive care unit because of water poisoning.
Well, besides water, there are other things that do not contain calories – for example, pure cellulose. This stuff is not digested and absorbed by the body.
However, gastrointestinal motility needs to consume energy. If you eat a large amount of pure cellulose, you will therefore consume a certain amount of extra energy. The disadvantage is also obvious – it is not good. Eating pure cellulose is no different from eating dirt, right?
Well, since this path is not possible, let’s think of another way: as we mentioned earlier, some people have a high thermic effect on food no matter what they eat, and this kind of people digest food with more “effort”. Some people keep it very low and digest food with less effort.
Is there any way to make our digestion of food more “laborious”? Then, no matter what food we eat, we will consume a lot of calories and never have to worry about losing weight again!
This can be done. There are many papers mentioning the same point, that is – more exercise! Whether it is a long period of aerobic exercise or a short period of anaerobic exercise, can effectively improve the body’s food thermic effect. In other words, if you exercise and then eat, you burn more calories when you eat!
Is it possible to exceed 100%?
I don’t think so. For every hour of exercise, the increased “thermic effect of food” results in an energy expenditure of only 7-8 kcal. This value is not even in the same order of magnitude as the energy consumption caused by the exercise itself.
Since the current “negative-calorie foods” are all watered down, is it possible to create real “negative calorie foods” in the future?
I think it is possible, but difficult. If we want to achieve the goal of food with a caloric effect greater than 100%, in addition to the food itself needs to be extremely low in energy, and it must have the ability to “change energy metabolism”. In other words, such a food may not be food anymore, but has the characteristics of a “drug”.
From another point of view, we all want to lose weight by “eating”, but it can be achieved by any means, not necessarily by consuming “negative calorie food”. For example, you can consume some foods rich in “soluble fiber”.
This is because the “soluble fiber” in the food can enhance the feeling of satiety of food. This way we eat less at each meal, the total calorie intake will also be less. This is actually much more reliable than “negative calories”!
Common coarse grains and vegetables are rich in soluble fiber. Nowadays, there are many beverages that deliberately add soluble fiber and label themselves as “diet drinks”. In fact, the principle of weight loss is very simple, it just increases your sense of satiety, so you eat less.(Sugar-free cola with added soluble fiber is said to make you slimmer, can you believe it?
Here is an aside: some time ago, I heard about the “apple diet” which only eats apples for three meals, and the “banana diet” which only eats bananas for three meals in order to take in fewer calories. For this similar “single food” diet, the short-term results may be significant, but it is difficult to adhere to a long time, after which it is likely to rebound. So the negative calorie diet is not so reliable.
If you want to lose weight reliably, you should control your energy intake and exercise more. Do not blindly believe in some strange “weight loss recipes”.
The “negative calorie foods” on the Internet are not reliable, they do not get thinner the more you eat.
Real “negative calorie foods” exist, such as ice water and pure fiber. But the “weight loss effect” they bring is negligible and negligible.
The thermic effect of food varies for each individual. More exercise can increase the thermic effect of food (though rarely).
If you want to use “eating” to lose weight, you can also consume some “soluble fiber” to increase the feeling of satiety. But don’t believe those strange “weight loss recipes”.