Strong defined jaws in men are a sign of high testosterone and optimal hormonal balance, those blessed with a completely intact and high functioning endocrine system, have an overall advantage which may allow them to thrive off of diets that would be disastrous for those less endowed.
People like Herschel are clearly genetically blessed and his being able to sustain his athletic prowess on his current diet at his age is a testament to his personal attributes (hard work had allot to do with it as well), but by no means is his success an indicator of the superiority of his diet.
I know its to soon but I say this out of respect: even Jack La lame Had moved toward vegetarian eating during his last 20 years and was even eating soy protein religiously, but he still had such a prowess and a will to live that he managed to do well and lived to be a respectfully old age, even though I contend he had the potential to live well into his 100s if he had followed a more natural diet during his later years.
Perhaps Hershel is burning the candle at both ends and although he could maintain his edge for a few more years I doubt it could last past the mid to late fifties, unless he uses growth hormone like good old Rocky, or perhaps he is just that well constructed like George Forman and I shouldn't make such accusation, forgive me if I am wrong.
