The truth about Intermittent Fasting for Weight Loss
Do not blindly follow trends, avoid best-sellers and always do your own research (DYOR)
Disclaimer: I am not a doctor or anything related to medicine and have no degree in nutrition. I am just a curious cat and this only represents my own opinion and it merely informative.
Before starting Intermittent Fasting (or any other weight loss program) you should consult a health professional, especially if you are pregnant or have a medical condition.
What is Intermittent Fasting?
In a nutshell: it is an eating pattern that divides your day into two windows, one for fasting and one for eating (instead of dividing our days into number of meals as we normally do). It is also known as Time-Restricted Eating (TRE) which, although similar, are different concepts (one puts its weight in the fasting window and the other in the feeding one) and is also more aligned with circadian rhythms.
How long do these windows last?
There are different approaches, but as the old saying goes: more is not always better. I say this because there are some of these “types” of fasting (with fancy names like OMAD, WHF, etc.) that basically try to stretch the fasting windows to the point of unhealthiness as if it were just another absurd competition of human beings.
What is the most popular then?
It is known as 16:8. 16 hours of fasting (which seems like a lot at first glance but we have to keep in mind that half of the way we already do it since we fast while we sleep) plus 8 hours to eat, for a total of 24 hours (one day). That said, note this: just because it is the most popular doesn’t mean it is the best for everyone.
Is it a diet?
No, it is not, as I say above it is an eating pattern. Most people incorrectly call anything related to food (even when it’s just a menu) a “diet".
Is it easy to do?
Basically it boils down to defining a suitable time window in which to meet your dietary needs BUT you may have to change your current meal schedule, or adapt it to your activities, work or personal relationships (this is why, for instance, people prefer to skip breakfast, as dinner is considered a more social meal in most cultures), which is not always easy, neither socially nor psychologically speaking.
Is it suitable for everyone?
No, it is not. Although it is generally considered safe for healthy adults, you should consult a health professional first, especially if you have any underlying health conditions.
Does it have any impact on our health?
In a way it can be, but it is definitely not the elixir of life as most people try to sell us.
Why is it so popular today?
Because life revolves around cycles and trends. And so do diets. There were other diets (I won’t say their names or supposed inventors) but in the last few years this is the most revolutionary “diet” for content creators and celebrities (the fact that the latter “group” promotes it and/or the use of the word “detox” are two of the biggest red flags when talking about anything related to nutrition) for the usual reason: they sell it as shortcut, and people generally love all kinds of shortcuts.
Is it the ultimate way to lose weight?
Definitely NOT.
Calorie restriction
Without beating around the bush and sticking to the topic of the post: skipping breakfast or fasting a reasonable number of hours means nothing to our body and this eating behavior does not affect our weight in any way (even if we do exercise during/after it). Caloric restriction (burning more calories than you take in; eating fewer calories than you need on a daily basis) is the only way to lose weight. Period.
What happens here, when we do Intermittent Fasting (IF for short), is simple: we have a smaller window of time to eat than we are used to, thus reducing the amount of food and the number of times we are able to eat. Therefore, unconsciously, we eat fewer calories, so we lose weight.
If that logic doesn’t work for you, ask yourself: if you ate once a day (also known as One Meal A Day or OMAD) more calories than necessary but fasted the remaining 23 long hours, what would happen (if prolonged over time)? It’s easy, you would get fat.
Whether to lose, gain or maintain weight, caloric balance (calories in — calories out) is the only meaningful thing, regardless of meal times, time windows and/or number of meals. It’s as simple as that.
Thoughts on Intermittent Fasting beyond Weight Loss
There are very few studies on IF for weight loss and/or other health benefits and most of them were conducted using a small group of people, no control group, or worse, a combination of both.
Consequently, there are no relevant conclusions on significant changes in body composition, energy expenditure, improved cognitive function, improved hormonal health, strengthened immune system, improved performance, cellular tissue repair, prevention of aging, prevention of disease or changes in markers of cardiometabolic health, when performing Intermittent Fasting. So if any (or all) of the listed supposed benefits are part of your goal you can always achieve them, as is often the case, by following the timeless advice: eat well, sleep well and don’t be a couch potato.
And speaking of speculations and half-truths: many content creators (Youtubers/bloggers; some even wearing a medical gown) appeal to the increase in autophagy (process by which the cell breaks down and destroys old, damaged or abnormal proteins and uses them for energy; thus theoretically reducing the likelihood of developing certain diseases and prolonging life expectancy) during IF, which sounds promising, but coincidentally they all forget to explicitly clarify that the increase in autophagy triggered by fasting/starvation has only been tested in laboratory animals (mice). In other words, researchers are still unsure whether the increase in autophagy is actually beneficial or harmful, how to actually measure this autophagy in humans, and how many hours we have to fast for this much-trumpeted increase to be triggered (data cannot be extrapolated blithely, since, for example a mouse is only able to survive without eating for two/three days before dying, whereas a human can go without eating for weeks…) so non-scientists are simply lying.
The biggest problem here is: throwing out inconclusive data about IF and telling the public that it is the Holy Grail, with no real underlying and based on “what the trend says”, is grossly irresponsible (I once read that it could even cure cancer….) and can be dangerous, leading to eating disorders: it’s not the first time (but I hope so) I hear over someone stressed because they are starving BUT they haven’t done their “16 hours” yet and they have to wait to eat and/or other anti-social behaviours like not going out for dinner because “I would like to BUT I can’t because I’m fasting at the moment, sorry”…
All extremes are bad. For everything. Run away from them.
Having said all this, what has been shown is that adherence to a Time-Restricted Fasting (TRF) schedule is very high (compared to other complicated or time-consuming methods, such as calorie counting), which may lead to some subtle but less bombastic benefits in the med-long term: it kind of pushes us to eat dinner early, which usually means we leave enough time between dinner and bedtime, which improves sleep quality; by having a window of time and not the whole day to snack or visit the fridge on a whim, it unconsciously educates us to be much less glucose-dependent; etc…
Just try, if you do it or you want to do it, to do TRF in a way that is not too tight. If you get hungry or have a dinner or whatever, just stop the timer a and keep going. It’s a long run in any case.
Peace.
