> If I restrict for three days a week, eat normally the other three, then add a relative "cheat" day between the two, am I possibly getting most of the same benefit anyways?
Unfortunately, we are more slaves to our bodies than one would think.
The calories you eat are almost exactly the same as what you burn.
And if you do not believe, try dividing the extra weight of a person by the number of days they lived to see how little extra calories they consumed over their lifetime.
Only a tiny imbalance is enough for a person to get overweight but it also means that it is really, really hard to eat any more or less than one is actually using for energy.
The biggest contributor to how much calories we actually use for energy (and based on above: consume), is our metabolic rates and activity. And metabolic rate does not differ a lot between people, the only thing that differs significantly is activity level.
So when somebody says "eat less calories to live longer" what they really are saying you should be less active.
> And metabolic rate does not differ a lot between people, the only thing that differs significantly is activity level.
Resting metabolic rates decrease in obese people, and stay lowered even if they lose weight.
Combine that with leptin resisance and it really is no wonder why it's so hard to lose weight once you have it and more than 90% of attempts persistently fail. This is why I do not like armchair "pills don't solve everything" takes, because in the case of semiglutide, it does help a lot getting over the leptin resistence induced permanent hunger feeling, just like Metformin improves insulin resistence.
> Resting metabolic rates decrease in obese people, and stay lowered even if they lose weight
It very much depends on how you lost weight.
You can be losing weight while maintaining high BMR. They key is to maintain high activity level and be able to eat to satiety regularly.
If you just cut calories consumed the body will try to defend from perceived starvation by cutting on activity and metabolic rate. You become sluggish, you feel cold even on a hot day, etc.
But you can also cut average calories consumed in relation to caloric requirements by moving a lot and practicing intermittent fasting where you eat to satiety from time to time (once a day, once every other day, etc.)
> (...) and it really is no wonder why it's so hard to lose weight once you have it and more than 90% of attempts persistently fail. This is why I do not like armchair "pills don't solve everything" (...)
I had two attempts at losing weight. I lost over 70 pounds both times. After the first time I regained it all within couple of years. For the second time I decided to rethink entire process and treat it as an engineering problem.
My results is that, to lose weight permanently, one has to learn new habits and essentially become a person that person that deserves lower body weight.
Which is what I did, I learned to eat better (cut all sugar, soft drinks and most carbs), stop snacking, restrict feeding hours, add activity every day throughout the day (running every morning, taking walks in the evening, sprinkling the day with small activities like buying groceries rather than driving to a mall once a week, etc.) It works.
It's clearly true that over the long term, calories taken in will be roughly equal to calories burned, minus a tiny delta reflected in weight change.
However, what the parent is asking is whether we know that the longevity effect is due to persistently low calorie intake (which will result in lower body weight, so that an equilibrium can be reached that's sustainable at that lower caloric intake), or if instead it might be sufficient for the body to receive intermittent signals of caloric deficit. Personally I don't know the answer to that question; I'm not sure if it is yet known.
Quite right on "Only a tiny imbalance is enough for a person to get overweight". Quick mental experiment: say I overeat 1 apple per day, that's ~ 90 kcal, that's ~= 10 grams of fat x 365 days == that's 3.65 kg per year. Over a course of only 10 years, that's extra 36.5 kg of weight I'd put on! From an imbalance of only 1 apple per day.
Unfortunately, we are more slaves to our bodies than one would think.
The calories you eat are almost exactly the same as what you burn.
And if you do not believe, try dividing the extra weight of a person by the number of days they lived to see how little extra calories they consumed over their lifetime.
Only a tiny imbalance is enough for a person to get overweight but it also means that it is really, really hard to eat any more or less than one is actually using for energy.
The biggest contributor to how much calories we actually use for energy (and based on above: consume), is our metabolic rates and activity. And metabolic rate does not differ a lot between people, the only thing that differs significantly is activity level.
So when somebody says "eat less calories to live longer" what they really are saying you should be less active.