That you should eat five times a day is one of the most common catchphrases in the world of dietetics; however, it has no scientific basis. What is certain is that it is very convenient advice for a certain food industry.
There are few areas of human knowledge in which we can find so many lapidary phrases and “lifelong” advice as those collected in the field of nutrition. Most of these catchphrases survive – and even grow and develop – from generation to generation, forming part of popular “culture.” Many of them, moreover, transcend this sphere of knowledge and acquire the category of irrefutable truth when they come from your grandmother when they are mentioned on the radio or on television, when they are found in black and white in some book (regardless of its genre) or when they come out of the mouth of a professional in a white coat. If said professional is a doctor, then that advice is the ultimate truth.
In this context, all current generations have the advice that for health and weight control (even to lose weight) the best thing is to eat 5 times a day. Or even more. And so on. Beyond the widespread and rounded nature of the matter – I am referring to the tendency we have to order things in threes, fives, or ten – the truth is that science has not found reasons that serve to support this advice. At least, in a general way and for everyone.
5 meals a day, reality or myth?
It is not a reality nor a myth: it is advice that lacks consistency. In some circumstances and for certain people it will be valid advice, and in other moments and for other people it will not be. The worst thing about this lack of definition is that, with science in hand, we are not sure which people will benefit from it and which will not. That is to say, and although it may seem incredible, there are published scientific studies that support the advice and others that, precisely, lean towards the convenience of reducing the frequency of daily intakes. On the one hand, among the first, those that support including 5 or more meals a day, suggest that a greater frequency of meals can reduce the risk of weight gain. But, on the other hand, and at the same time, there are studies that observed that 1 or 2 meals a day are better than 3 or more. Thus, and to make it clear that nothing is clear in this area, an important meta-analysis determined that the differences in weight and body composition between people who follow a high frequency of daily intakes compared to those who have a low frequency are insignificant.
It is for these reasons that, for example, serious scientific consensus regarding the impact of meal frequency on weight status categorically states that this is a controversial and inconsistent relationship.
Eating 5 times a day, is a very modern but unreliable advice
The number of meals eaten throughout the day is not a universal standard, nor has it ever been, by any means, throughout the ages. So much so that it can be said with little room for doubt that even eating three meals a day is a recent behaviour. What can we say about eating five? Let’s see.
In Roman times
In ancient Rome, there was only one substantial meal a day, and this was usually eaten around 4:00 p.m. and was called coena (yes, from which our “dinner” comes). In fact, at that time it was assumed that eating more than once a day was not healthy. It is true that, on some occasions, they could also include one or two particularly frugal meals: the ientaculum in the morning, and the prandium around midday. These were frugal, light, and quick meals, which were not at all “standardized” and which were made (or not) according to the needs and tastes of each person.
In the Middle Ages
It is believed that the systematic inclusion of a morning meal (what we would now properly call breakfast) arose timidly as an influence of monastic rules on the general population. Thus, in the monasteries, after having dedicated a good part of the night to prayer, the custom of having a first meal to break the fast of the night vigil made the leap to the popular class, which in that environment was called colazione (breakfast in Italian), a name that comes from one of the texts that were most frequently read in the monasteries ( ” Collationes” by Giovanni Cassiano ) while the monks ate in silence (at whatever time).
In the industrial revolution
The introduction of a greater number of daily meals coincided with the Industrial Revolution, especially with the upsurge at the end of the 19th century and beginning of the 20th century. In this scenario, at least three characteristics coincided, which have served as a driving force for many of the changes that, compared to ancient times, we now recognize in our mealtime agendas:
- The schedules of the working day necessarily shaped the rhythm of meals. In addition, given the effort that those days required, it became essential to include, without fail, a relatively heavy meal before starting work. And breakfast is here to stay (whether we need it today or not).
- Electricity, and with it artificial lighting, made it possible to lengthen working days and, with it, to eat after dark. In other words, we postponed the time of the last meal.
- A new food industry flourished at the pace of the industrial revolution itself. And with it appeared the first processed foods and, beyond that, the ultra-processed foods. All this added to the above, and together with the legitimate commercial interests of these manufacturers, ended up in the message that we know today referring to the supposed benefits of being on a continuous feed, that is, eating 5 or more times a day. A message that in many cases responds more to marketing interests than to the real need to eat so many times a day.
Today (and for 50 years)
Nowadays, in Western culture, it is a common idea that daily food intake should be divided into three full meals: breakfast, lunch, and dinner. Three meals that, as if they were not enough, some recommend finishing with two snacks (lunch and afternoon snack) appealing, almost always, to the benefits of controlling appetite. Thus, the message “eat 5 times a day (or more)” and regardless of the circumstances that originated it, has been part of the discourse of many health professionals, many recommendations, and many media outlets for two or three generations.
Alleged benefits of eating 5 times a day
Given the lack of definition in which we move, in which this advice cannot be considered good or bad, it is only necessary to mention the arguments put forward by those who defend it. Thus, and in general, the causes of the alleged benefits of eating more times a day would be:
- Better appetite control.
- Better control of plasma glucose levels (more uniform).
- An increase in the thermogenic effect of food, that is, the energy expenditure derived from the processing of food.
Alleged dangers of eating 5 times a day
As expected, in this section we cannot guarantee against “dangers” since, as we have already seen, the advice cannot be classified as either good or bad. In this case, the main reason for stating that “eating 5 times a day” is bad is the obvious one, that is: that eating more times than less leads to overeating beyond needs and thus to increasing the risk of obesity, diabetes, cardiovascular disease, etc.
How many meals a day should you eat and why?
I think that before worrying about certain details, it would be essential to have other more important details under control. And never move on to evaluating those secondary details until we have the first ones under control. If you allow me, I’ll give you an example.
Rather than thinking about how many times you should fill up your car’s fuel tank to get better performance and fuel consumption figures, it would be better to worry about the type of fuel you put in, the way you drive, and the amount of fuel you add each time you fill up. So, in the field at hand and rather than worrying about biological clocks and the number of meals per day, you should consider:
- The food choices you make and basing your diet on “natural” foods rather than ultra-processed products. If your daily life is full of the latter, with sweet and salty snacks, with pre-cooked foods of dubious origin, and in general, if you do not control what you eat (neither buy nor cook), it does not matter how many times you eat throughout the day. So improve your choices.
- Review your general lifestyle. Along with your diet, and just as important as it is, your physical activity is another pillar of your health prognosis. Staying active is essential. The more activity you do, the more you will have to eat, it is unavoidable. It remains to be seen whether this increased intake is achieved by increasing the number of these or by increasing their volume. Always, of course, taking into account the previous point.
- Take into account the sensations of appetite and satiety. We often eat out of inertia or even to comply with the advice that “we must eat 5 times a day.” And we do so without being hungry. And what’s more, we do so with standard quantities, whether or not we have the appetite to eat so much. So, the advice at this point is that you eat consciously, rationalizing that appetite and satiety without letting go of the first and second points of this section.
The 5 meals a day diet for weight loss, does it work?
No. It doesn’t work. Just like no diet works for weight loss. None. When we assume the concept of “diet” as that popular strategy of putting on and taking off (actually “put on and take off”) we incur the worst of mistakes. An adequate diet, to maintain or to lose weight, has to be lifelong. For life. Of course, in the short term, the fact of organizing their diet and having five meals a day will have helped some people (if that is the case) to lose weight. But that loss will not last as long as they do not convert that “put on and take off” diet into a dietary style forever.
Finally, and in the face of these frequently asked questions, it is curious that, under the pretext of losing weight, such disparate proposals as eating 5 times a day and intermittent fasting coexist at the same time. Without a doubt, we know that we will find studies in the scientific literature that affirm that either of the two systems is valid. However, the conclusion that we must draw from this contradictory reality is that neither of the two systems is valid for losing weight in terms of Public Health. Think about it, if it were otherwise we would already have solved the problem of obesity in the world. As always, both with the “diet” of 5 meals a day, as with intermittent fasting, the keto diet, the paleo diet, the grapefruit diet … or whatever, the important thing is the attitude of each person when it comes to abandoning bad lifestyles and embracing, with conviction and forever, better ones.