Posted 02 August 2008 - 03:13 AM
Nice Topic! This is probably a good place to introduce my hypothesis that there could be a difference between living vigorously and living long. Ever notice how many of the longest lived people on the earth are short (and usually thin). This connection almost certainly has to do with hormones. What influences hormones the most? Genetics and diet. Take someone who lives on a protein-rich paleo diet. Almost certainly, he will have an abundance of testosterone and good body composition (because the promotion of growth-type hormones). His resistance to disease and ability to recover are almost certainly very high for many types of injury. Let us contrast that with someone who is on a CR-type diet. His absolute protein intake will almost certainly be less than that of the paleo group. Also, almost all levels of growth type hormones, testosterone, DHT, DHEA, growth hormone, insulin etc. would be less. Resistance to disease is heightened because of some hormetic-like function on cells because of the reduction in caloric intake.
Debates rage on for the perfect range of protein, fat, carbs, but even with some genetic optimizations, there is going to be some type of ratio that promotes the most longevity. And there will be a trade off for body composition! Want to have muscles, sex drive, and so on? You might not live as long (how much is the question), but you can always hold out for genetic cures.
The main question is -- what is the real difference in longevity from someone who is really doing all they can to increase longevity. Once again, I see a lot of the paleo types looking really good and muscular even into there 80s, but what happens once they hit 90+, hmmm. Some of them list keeping insisting that keeping insulin as low as possible (on protein rich, high fat, low carb diet) is the best way to longevity. There is just no way this is possible on a diet that might keep insulin low, but other growth type hormones sky high! (think about how SHBG drops on a high fat diet!) Not to mention we don't know everything about the effect of certain macronutrients on cell turnover (like protein) <--- akin to what is happening when are DNA is replicating, but not perfectly. Some of the reason why the high carb diets around the world have been associated with longevity may be because of the anaerobic metabolism they may partially promote (once again, this may be hormetic) - where a high fat diet might be partially detrimental because of the oxygen-rich environment it promotes.
Now, if someone told you that you'd live only 2-5 years longer (thats probably what we are looking at with non-genetic interventions) on a diet that makes you look weak would you really do it? When you could be looking really strong and vibrant (the choice is really up to you).
And if you have any doubt that a lower amount of growth hormones is beneficial for longevity. Just look to the exceptionally long-lived. Every year they live they lower the amount of growth-type hormones they produce (and this is helping them live even longer! --- think about the difference between his testosterone production at age 30 compared to 100). Just think about what a farce HRT might look like in the future (in terms of sacrificing long term health for looks).
Seems to be that you want a diet that lowers all types of growth hormones to the lowest levels. We need to analyze what ratio of protein/fats/carbs this would be. After knowing what causes the greatest longevity without detriment, we can then tweak the ratios for adding muscle growth for those that want a little more without sacrificing much overall longevity (and dont want to look like a twig)-. Then, we can hold out for gentic therapies!
Sorry if this contains some bad english!
