It worked very well in small organisms, once you go to apes the results are much less clear: https://www.theverge.com/2017/1/17/14287708/caloric-restrict...
In general, being overweight is a far, far larger problem in the West, and being underweight is extremely rare outside of eating disorders like anorexia. There are people who are naturally skinny due to how their metabolism works, but they are rarely truly underweight.
[...] according to 2010 data from the Centers for Disease Control and Prevention, these are the measurements of the average American man:
Height: 5 feet 9 inches (69.3 inches) Weight: 195.5 pounds Waist circumference: 39.7 inches
https://www.cdc.gov/nchs/data/databriefs/db288.pdf
That's far more a concern than whether men need to bulk up or not. Which naturally happens as men age and their metabolism slows anyway.
Anecdotal evidence from Europe: in our industry, culturally associated with obesity, I meet roughly equal amount of obese and underweight people. And I seriously doubt those underweight people spend time in the gym.
The reason could be a tiny outlier minority.
You used the term "many".
... or me at 18. Damn I miss that metabolism.
Even telomere bound is not enough.
It's likely a set of advanced repair and local homeostasis so that feels still execute the complex maturing program correctly.
Too many senescent or damaged cells might just break the conditions... And mitochondria and cells have excellent mechanisms of dealing with reactive species they make, but sometimes chemicals leak in.
I'd be more concerned with infections and resulting damage at this point, plus toxic damage. Including endogenous like glycation.
And would there be a way you think to test if that's really the case?
I have talked with some people who had like severe reactions to the drug who managed to get some kind of mitochondria testing and it would say stuff like "30% of the active sites are blocked on the mitochondria"
> In humans, the long-term health effects of moderate caloric restriction with sufficient nutrients are unknown.
This is true of both animal studies, and preliminary statistical data on the few humans that have been trying CR for a few decades now. There is health improvement, but that's because CR is watching your diet, which is generally good for you. You correct for those factors and the effect basically disappears, at least into the high level of noise that comes with low sample sizes.
But if you still believe in CR, even easier is taking resveratrol. My understanding is that the caloric restriction basically causes the production of resveratrol which is the cause of the beneficial effects in mice. So take resveratrol and eat a normal amount of healthy food should have the same result.
This is true for almost every group including scientists studying nutrition, it changes frequently.
(My gripe is less with individuals, who are inconsiderate - it's primarily with aforementioned entertainment sources that purposefully twist and misrepresent actual research and play on people's fears.)
Not having orthorexia among such a group would be like farting in public in less fortunate groups.
(Which includes people into Goop and such -- hardly the "hackers" that want to analyze and hack the human body).
Cut calories and you cut the amount of cardio and strength training you can do. This cuts muscles mass, bone density, and takes away the IQ-increasing brain simulation factors away. I am not sold at all.
Sources: https://en.wikipedia.org/wiki/Calorie_restriction