Although it is generally recommended to eat five meals a day, the reality is that this advice lacks both nutritional logic and scientific evidence.
For years we have been bombarded with the idea that “eating five meals a day is healthy”, as if the number of times we eat was one more factor to take into account. In fact, this premise is one of the most often added in the long list of tips to lose weight, even by health professionals in general and doctors in particular.
The logic behind the advice to eat five meals a day is that, by eating more times, " the metabolism is accelerated ", which will mean that at the end of the day we will burn more calories than if we had only had two or three meals a day. And, to curl the curl, some add to this statement yet another theory, such as the fact that " eating more often and in less quantity controls appetite better "; Or what is the same, eating less times a day would cause an increase in appetite and would make us eat more in fewer meals. As we will see below, all these claims are false and lack evidence.
Five meals a day does not speed up the metabolism
If we analyze well the claim that five meals a day accelerates the metabolism, objectively, it falls under its own weight.
Although it is true that there is a part of daily energy that we spend in food processing, called Thermic Effect of Feeding or TEF in its English acronym. In other words, the thermal effect of food, which at a general level would imply around 10% of the total energy we spend per day. Food is not absorbed by itself, and the body needs to use a certain level of energy for all of these metabolic processes.
However, the TEF does not increase or decrease according to the number of meals, but by the total number of calories ingested during the day. It does not matter if we divide them into three meals, five meals or ten meals. The TEF will always be approximately 10%, a percentage that can vary (not significantly) depending on the nutrients, being somewhat higher if fiber or protein is consumed, which require more energy for their metabolism. Therefore, the number of total meals has a useless effect, and the hours that pass from one meal to another also. What matters, I repeat, is the total calories consumed throughout the day.
Five meals a day does not decrease appetite
The second fallacy regarding the need to eat five meals a day is that, with more meals, better appetite control and less hunger, so fewer calories will be consumed per day. Again, if we analyze this statement, it falls under its own weight.
Actually, the frequency of meals as a method of controlling appetite is something very personal, and more cultural than nutritional: in the past, when humans needed to hunt to survive, eating two or three meals a day was luck. In medieval times it was also quite common to eat only three meals a day. Nowadays there are five for a more cultural factor, since the hours of "lunch" (or mid-morning) and the "snack" (or mid-afternoon) are used to eat something because they are periods of time that coincide with work breaks, but not because of an intrinsic need of the organism.
In fact, reducing the frequency of meals tends to make people in general feel more satiated than the other way around, especially when trying to lose weight: eating three larger meals instead of five smaller ones will better control your appetite, since If we increase the number of meals, we must reduce their caloric density (unless we want to gain weight, of course). And having "small meals" usually produces hunger, not satiety. Or, on the contrary, easier to overindulge in such meals.
Therefore, the only situation in which there would be any benefit from increasing the number of meals would be just the opposite of what most people usually look for: when you want to gain weight, as in the case of high-calorie diets to gain muscle mass. In this case, it would be convenient to increase the number of meals, because that way you can consume more food more easily than if you try to divide all those extra calories in just three large meals.
Five Meals a Day: What the Science Says
In case these explanations have not been enough, there are also studies in this regard. For example, a study published in Annals in Nutrition & Metabolism in 1987 and a more recent one, published in the British Journal of Nutrition in 2010, reached the same conclusion: eat five meals a day, or increase the number of meals in in general, it neither accelerates metabolism, nor improves blood glucose levels, nor controls appetite better.
Later, in 2015, a review published in Frontiers in Nutrition again concluded something similar: increasing the number of meals per day has no benefit for the body.
Therefore, as a final conclusion, the moral of the matter would be that the number of meals depends on each person in particular and their long-term goals: if you want to lose weight in the form of fat, it is better to eat three large meals; If you are looking to gain weight in the form of muscle mass, eating five meals a day (or more) would be a good option. Decreasing the number of meals does not alter the metabolism, or lose muscle, or anything at all.
Ketosis is a natural process the body initiates to help us survive when food intake is low. During this state, we produce ketones, which are produced from the breakdown of fats in the liver. The end goal of a properly maintained keto diet is to force your body into this metabolic state. We don’t do this through starvation of calories but starvation of carbohydrates.