any unhealthy side effects of only eating one meal a day? what if that meal is 1800+ calories?
To be honest dieting is only good if you're trying to get to a "goal weight" and you're capable of maintaining a weight. If you're not and that's what got you fat to begin with.. You need a holistic lifestyle change.
Said another way, you should adjust intake until weight starts coming off slowly. You'll reach a point where you either lost too much, or stopped losing, and adjust slightly accordingly. Then stay at that intake forever(assuming it's healthy).
Edit: Yes I'm wrong I should have said "if you eat 1800kcal of clean food", I forgot the existence of fast food because it is not something common in my country
Meaning it’s very easy to eat that depending on what it consists of.
Ice cream too is crazy - one Ben & Jerry’s is like 1600k
Fasting (intermittent and otherwise) causes several physiological responses that have a wide range of health benefits, including reducing risks for cancer and heart disease, and even completely reversing diabetic symptoms for some people. It is absolutely NOT some cheesy self-help way of tricking yourself into eating less because you "just can't fit any more in there" -- you completely made this up.
Nuts, cheese, and vegetable oils are really energy dense.
I also don't consider myself to be a glutton a have a BMI of 21.
https://www.mcdonalds.com/us/en-us/about-our-food/nutrition-...
We dove a lot of pizza places, but it is Italian pizza and it is not as caloric as the American version, ours is made with 200grams of dough and has less stuffing as possible, one pizza should be around 800kcal and majority of people I know usually eats 3/4 of it and leaves the remaining 1/4 for the day after
If you make a regular meal, one meal a day nets a negative of 1300/1500 calories per day, which will cause considerable muscle tissue loss (note how the parent writes "losing weight", not "losing fat", but also "yes, I have significant fat even at 150lb and 5'10"), besides having no energy.
If you make instead a massive mels, you're going to give a massive glucose shot to your body. I haven't gone to such extreme, but the times when I happened to do something similar (one huge meal, even with an overall negative daily intake), I ended up accumulating fat rather than losing it. I suppose that in a calorie deficit context (=dieting), the body takes advantage of a huge meal to build some deposits up (and unfortunately, deposits are everything except muscles...).
Dieting's hard, there are no cheap tricks, unfortunately.
Unfortunately I've gone back to some of my old ways over the past 9 months or so with restaurants and bars reopening, and I've gained back some of the weight. This tells me that it's not really how many meals I have, but what's in them, and how many calories. So I'd probably be fine with two or three meals a day, just healthier choices and fewer overall calories. But I don't believe one meal a day is a problem; just it isn't necessary, and you can still lose weight with a more normal meal pattern.
This meta-review seems to conclude fasting + resistance training might not only be harmless but actually beneficial https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7468742/
I think for most people who are looking for weight loss - this is not as much of a concern and going to the gym would likely be an extra hurdle for them that would make it too hard. So, 1 meal a day is relatively straight forward.
It is true that caloric deficit always causes muscle; the issue is how much one loses.
I'm not aware of any evidence to support that. Fasting patterns have been studied, and I'm not aware that any studies on fasting have shown the effect you describe, but I've not followed the research for some years.
In terms of anecdotal evidence, I have regularly measured body fat percentage during diet periods, and I do see steep drops in body fat percentage when I've done intermittent fasting with the vast bulk of my intake coming in a single meal (2k calories plus during one period). As mentioned elsewhere I now prefer 4-5 days of drastic cuts and eating normally a few days a weak, and without confining it to a narrow period, but I also did IF for many months while at my peak of lifting both in a deficit and not, after having previously done slight deficit dieting in the past, and could compare the difference, and I didn't see the slightest hint of the effect you're claiming.
I wouldn't do it every day, but mostly because I find it too hard, but I do currently aim for ~600 kcal 4-5 days a week to drop down. I do it in multiple small meals, but I've also done intermittent fasting with narrow feeding windows. On the remaining days, I eat normally - I don't binge.
It'd likely have more of a negative effect on my muscle mass if I did it every day, but if I did, I'd also reach my target weight far faster, so even if I'd had to spend time bulking up again later I'd have done that if I was able to stick to it, but I know from experience I'm not.
I also power lift (not competitively), and I've had steady progress while doing that, with the caveat I'm not at my peak - I wouldn't expect to progress with this diet if I was. But most people are so far off hitting limitations caused by food intake in their exercise it matters for quite few people.
People should keep up resistance exercise while on diets to reduce muscle loss.
It's not sustainable over long periods of time in that sooner or later you get to an inflection point where it impedes your progress, but it works when your body fat percentage is high, and for most people looking to lose weight it's simply not what they should be worrying much about.
That you accumulated fat with what you think was a net daily deficit sounds to me like it wasn't a net daily deficit. Intermittent fasting works, and limiting yourself to a single daily meal is not nearly long enough fasting periods to mess much with body composition. But it may have messed with your activity levels. It takes little change in e.g. dozing off on the couch rather than walking around to have an effect.
People are mostly more sedentary than they think and burn fewer calories than they think. When I was at my peak, exercising every day and lifting heavily 3 times a week, to maintain my weight I needed to keep my intake around 1800kcal because my life outside of that was not very active. I'm 185cm, and at the time I was about 93kg, with body fat around 15%.
Someone with a more active life outside of the gym might burn more. Many burn less. Kcal guidelines for adults have remained static for way too long with declining levels of physical activity, and people really should count calories for a few weeks and adjust their intake and figure out how little they actually burn...
I've always done weightlifting, although not competitively, as general support of the fitness regime (which may include other sports or not).
What I've observed is that when a dieting cycle goes bad, a short time after the end of it (to allow glycogen and water levels to come back to normal), I end it with approximately the same weight before the start. If/when I observe an increase in measured fat (which happens most of the times, on bad diet cycles), then muscle mass went down.
When I was pushing my body to the max every week, then the difference mattered to me too. But most people are not there, or anywhere near those kinds of limits.