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MushroomNovaCat t1_j7x5j76 wrote

Thank you for pointing this out. It was exactly my point in my comment. How can caloric restriction be said to lead to better health and longevity when it's inextricably linked to better diets? Wouldn't the better diet be assumed to be the real determinant? Is calorie restriction necessary at all or is it simply better diets that lead to better health and longevity? I think the answers are pretty clear, particularly when you consider what's known about the diets and cultural factors of so-called blue zones.


CotyledonTomen t1_j7xfnfk wrote

Its possible to over eat on food considered healthy. Its easier to feel sated on low calorie, high density foods, but you cant say eating the equivalent number of calories in burgers with toppings, wouldnt lead to the same result, without a study anyway.


MushroomNovaCat t1_j7xk1sq wrote

We can say that it wouldn't lead to the same result. There have been numerous studies linking highly processed foods to disturbances in the gut microbiome that lead to inflammation and chronic diseases which are far less prevalent in societies that have maintained their traditional cuisines, free or nearly free from highly processed foods.


jayboknows t1_j7zngdw wrote


As the authors noted, this can be seen in multiple species. In animal trials, caloric intake is often achieved by manipulating quantity of food, not type. This could suggest that energy would independently impact longevity, and that it's not simply a matter of eliminating highly processed foods. While animal studies are not the highest degree of evidence, they are often useful for determining mechanisms of action when confounding variables like this can be accounted for. This is not to say that diet quality does not also have an independent or synergistic effect on longevity, but it would point toward energy intake being a piece of the puzzle, at least.


MushroomNovaCat t1_j80fvzg wrote

Not necessarily, the reason being that animals are fed more fiber to keep them from being hungry in these studies and we already know that fiber is beneficial to health.


jayboknows t1_j80hz8h wrote

Diet composition compared to energy intake has also been investigated in animals. Read the introduction to the linked study and the authors discuss previous findings demonstrating CR working independently from diet composition.

“We recently completed a longitudinal study in male C57BL/6J mice (B6) initiated at 4 months of age in which the effects of the two diet compositions under ad libitum (AL) and CR conditions were measured (Mitchell et al., 2019). Independent of diet, male B6 mice on 30% CR exhibited significant improvements in health, survival, and a delayed onset of cancer with respect to AL-fed mice.”


MushroomNovaCat t1_j80ncwf wrote

I don't see any diet specifics listed. As I said, fiber is given to animals to account for the missing calories in these studies and we already know that fiber has beneficial effects on health, as was pointed out by this study.


MushroomNovaCat t1_j80o8cy wrote

I'll also add that we don't see the mood and cognitive effects of caloric restriction monitored in these studies. We already have several studies demonstrating that "hangryness" is real and has negative effects on mood and cognition which once again, circles back to my original comment. Just because we can recognize the benefits of certain practices even if we don't precisely understand them doesn't mean that those practices are sustainable or that they don't affect other areas negatively.


jayboknows t1_j81dmi6 wrote

I do not dispute that fiber has health promoting benefits. I do feel that it’s a bit of a straw man from the original point, though. The discussion seemed to be that the less processed food, in the blue zones, was responsible for increases in longevity, independent from CI. From that perspective, I believe the animal studies, where diet composition is the same (degree of processing isn’t different) and CI is the IV, are useful. I believe they provide evidence that energy intake affects longevity independent processed food consumption.


MushroomNovaCat t1_j81f8rp wrote

It's not a straw man, my point was that diet is not monitored in most of these studies as was noted in the study you linked and even when diet is monitored, it is still not equal because fiber is used to supplement the diets of the animals eating the calorie restricted diet, therefore the diets are not equal in nutritional value. There's more to a good diet than low amounts of highly processed foods as I noted in a different comment, a low amount of consumed animal products along with a good amount of fiber and adequate consumption of all essential amino acids, proteins, fats, carbs, vitamins and minerals is also needed.

There has not been a study that has established why caloric restriction results in increased health and longevity therefore we can't say that it's not the co-factors associated with caloric restriction (i.e., better diets, intermittent fasting, fasting correlated with circadian rhythms, etc.) that are primarily responsible for the beneficial effects rather than the restriction of calories itself.

My purpose in pointing out blue zone diets was to demonstrate that health and longevity do not require caloric restriction. My point was also to demonstrate that caloric restriction leads to hunger and hunger leads to impaired mood and cognition which has also been well documented in other studies. Caloric restriction has benefits but we can reap those benefits through a good diet, without restricting calories, without going hungry, and without affecting our mood and cognitive abilities.


CotyledonTomen t1_j7xr86m wrote

And what proof do we have than any of that is specifically related to longevity?


MushroomNovaCat t1_j7xvdq7 wrote

Because we have studies showing that people who consume less processed foods, who have maintained their traditional cuisines, live longer on average than people who eat highly processed Western diets.


Dabalam t1_j7zsmz1 wrote

I don't think that's accurate. The specific question we're asking is if you control for calories can you achieve the same longevity regardless of diet. Observational studies on people who tend to eat more calorie dense refined food do not control for calorie intake.


hooplala822 t1_j7zycp9 wrote

On the Huberman Lab podcast, an interesting note he made was that in a mouse study, obese mice that fasted lived as long as healthy BMI mice that fasted and both outlived mice that did not fast/did not calorie restrict


MushroomNovaCat t1_j80guu4 wrote

This particular study did not monitor diet so no, that question has not been answered. It's not understood why caloric restriction improves health and longevity, there are various competing theories which were outlined in a study someone else linked in a comment.