When I was younger, regular eating was considered healthy. Nowadays I read that fasting has benefits. I really want to know what is better and why.
Let’s assume same calories, nutrients and macro if that’s possible.
In: Biology
It actually does matter, a great deal, almost as much as what you eat.
Not a doctor, but I’ve got a decent amount of experience with fasting and can 100% confirm that it is so much more effective and satisfying than the old traditional diets that folks have been trying to follow (and usually failing at) for so many years. I’ll try to explain this as best I can, but honestly, I would get on Youtube and look up some of Dr. Jamnadas’ interviews about fasting, such as this [one](https://youtu.be/wGrWznkQWpE?si=rg8UEa0rAH8rXMMe). He’s a well-known cardiologist down in Florida.
The old school of thought used to be that it was a simple matter of calories-in/calories-burned, but what is becoming better understood in recent years is the effect that eating has on your body hormone levels.
In short, eating constantly means your body is constantly digesting new food, and you are constantly triggering complex metabolic responses.
Eating a single meal or confining your eating to a specific window of time means that you go through this hormone trigger process just once and then giving your digestive system a chance to rest.
It’s been awhile since I’ve talked about this or read about it, so I’m forgetting a lot of the terminology behind the science, but I would definitely recommend you watch the interview above or any of Dr. J’s interviews where he breaks this process down.
But yeah, if you can also go for longer periods of time without eating, your body will actually switch “fuels” from the food you’re eating to converting your body fat into ketones which are then burned for energy. I’m sure you’ve heard of ketosis, or keto diets.
With fasting, you are also giving your body a chance to start consuming and replenishing old cells through autophagy, so it’s kind of like internal housekeeping on a cellular level.
Research has indicated that regular fasting contributes to dramatic decreases in certain types of cancers, chronic diseases related to inflammation (IBS, etc), improved mental functions, etc.
In short, fasting is a much better option for not only losing weight but improving your overall health than simply reducing calories.
It doesnt realy matter (within reason). If you eat the same it is the same. The reason why things like interval fasting is a thing because most people eat less if they only eat in a short amount of time each day. Same goes the otherway if you have trouble eating enough (not only in calories but also in otherthings like protines) it often helps to eat in smaller amounts more often. But bothings are indivual things and not everyone has the same habits thats why what works for some doesnt work at all for others.
There was a study done a few years back (I think in Finland) that studied when a group of people ate and if it had any effect on their weight. I don’t think the study focused on anything else other than that or if it did the article I read didn’t mention it in their reporting.
The result of the study was that having many meals compared to one and their various timings had no effect on their weight. What did have an effect was the amount of food they ate (again this included amount of meals and their various timings). What they found and reported was that people could eat as many meals or as little meals as they wanted and the main thing that would affect weight gain or loss was how much or how little calories were ingested.
Take this for what it is – a half remembered reporting of a study. It’s entirely possible that I have misremembered something so please don’t take my reminiscences as medical advice.
Theres been recent studies showing that Fasting is no better than other forms of weightloss in terms of how much weight is lost for a given calorie deficit. By just reading the ‘headline’ result, many people are left wondering why use fasting for weightloss at all then? Well for a myriad of reasons!!
Lets talk about the downsides of Conventional CICO diets first. Usually these follow the S.A.D. (Standard American diet) of 3 meals a day plus several snacks….just calorie reduced versions. This means none of the meals or snacks are very satiating and one can be constantly hungry and feeling deprived. If you run too high of a calorie deficit eating this way you will constantly plateau and then YoYo regain the weight at the end because you crashed your metabolism. The reason is that eating that often spread across the whole day keeps your insulin levels raised most of the day. Insulin is the Fat storage hormone and you can only store fat not access and burn it with insulin in the blood. Your body doesn’t have enough insulin free hours in the day to burn enough fat to make up for the large dietary calorie deficit and so it has no choice but to lower your metabolism instead. As your crashing metabolism catches up with your diet intake you plateau. You cut calories even more or exercise more to restart weightloss, but your metabolism resumes the chase. You either reach goal weight or give up the diet. you don’t even go back to old bad habits but start eating what should be your new maintenance calories at your new weight….and you start rapidly regaining weight. This is because what should be your new maintenance is actually a large surplus relative to your crashed metabolism. As you regain the weight your metabolism recovers but you are back to where you started. You summon the motivation to start again but use the same diet plan again. The exact same thing happens and new you know what YoYo dieting is.
The main reason the recommended daily calorie deficit is only 500kcals a day is that this is close to what your metabolism would drop to simply due to the weightloss where it takes less calories to maintain and move a lighter body around. For example, My TDEE (Total Daily Energy Expenditure = BMR + Avg Daily activity = Maintenance calories) was 2400kcals at 200lb but will be 2050kcals at my goal weight of 145lb. So even if I ‘Crashed’ my metabolism with a conventional CICO diet, if my daily deficit was only 500kcals then I haven’t crashed it much beyond what it would have fallen to anyway at my goal weight.
The problem with a 500kcal per day deficit is that it means only 1LB a week of fat loss. This glacial rate of fat loss is easily potentially swamped and hidden for weeks simply due to Glycogen Water, Poop, Electrolyte water, Menstrual cycle fluid retention variability. So folks are hungry all the time on this kind of diet and yet they see virtually no progress for weeks on end and sometimes it even looks like they are going backwards because for example 3 weeks worth of fat loss was masked by as little as 1.5L of water retention…or constipation!! LOL No wonder so many throw in the towel on diets so quickly so often!! They either run a high enough deficit to see enough progress that keeps them motivated longer but end up crashing their metabolism and inevitably regaining or they run the recommended daily deficit, don’t crash their metabolism but see such slow progress they never lose much weight before giving up in frustration anyway.
Intermittent and extended fasting on the other hand you can run much larger deficits without crashing your metabolism because you’ve left more than enough insulin free hours in the day for the body to access and burn all the calories it needs to make up for the dietary calorie deficit and thus your body has no need to crash your metabolism. The real magic of IF/EF IMHO is in its Ghrelin Hunger Hormone suppression. Your body quickly learns to secrete this hormone at your regular mealtimes to remind you to eat with psychosomatic effects like hangriness, lethargy, jelly legs etc which people assume is low blood sugar or hypoglycemia but isn’t. If it was it wouldn’t just disappear as if by magic about the 2 hour mark when the Ghrelin surge subsides. If you skip a meal or meals only a few days in a row you deprogram that Ghrelin surge and as long as you didn’t move those calories to the remaining meals, you created a calorie deficit without having to be obsessive about calorie counting. With the Ghrelin surge deprogramed you don’t even feel hungry at or miss the old mealtimes. You still get to eat the same delicious food and portion sizes you always ate for the remaining meals so don’t feel like you are depriving yourself of anything. This is why IF can be so easy and so sustainable to do over the long term of weeks, months and years. The likes of Ozempic/Wegovy are leveraging a different hormonal pathway to suppress appetite and cravings and it frustrates me that folks are paying hundreds a month for those drugs when they could leverage their own Ghrelin Hunger Hormone for free with the same or even better results with IF.
So given the same macros, nutrients and calorie deficit, will you lose any more weight with Fasting? No. Will you be able to run much larger calorie deficits though without risk of crashing your metabolism for much faster weightloss and will you be able to keep the fasting ‘diet’ going much much longer because there is no constant hunger or sense of depriving yourself of anything. Yes.
So Calories in and Calories Out still matter even with fasting, but thats only half the story. The weightloss is coming from the Calorie deficit but that calorie deficit was able to be larger, was made easy to create and easy to sustain by the tighter eating windows and its effects on several of your hormones like Insulin and Ghrelin. Haven’t even mentioned IF’s tigher eating windows ability to cure any insulin resistance, metabolic syndrome or pre-diabetes you may already have developed, nor have I mentioned the inflammation reduction from gut rest, reseting the gut biome to a healthier ratio of good bacteria or the myriad benefits of fasting induced autophagy.
Put simply, IF is probably the fastest, easiest, most sustainable and most metabolically healthy way to lose and then maintain weight.
If you’re not an athlete, don’t have athletic pursuits, can actually consume all that food in that time, and don’t have underlying medical issues that prevent your body from utilizing glycogen/fat stores properly or require specific diets/nutrient timing, then yea doesn’t matter.
Most people don’t check all those boxes and also are emotionally affected by food so regardless of the lack of health ramifications, it would not work out for them
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