Anti-aging diets have been around since the 15th century, starting with the books written by Luigi Cornaro. Although I addressed the history of Luigi in my book The Anti-Aging Zone written more than a decade ago, it bears repeating. Finding himself near death at age 35, Luigi Cornaro went on a strict calorie-restricted diet consisting primarily of an egg yolk, some vegetable soup, small amounts of locally grown fruits and vegetables, a very small amount of coarse, unrefined bread and about three glasses of red wine per day. He wrote his first anti-aging book (The Sure and Certain Method of Attaining a Long and Healthful Life) at age 83 and his third book at age 95. He finally died at age 99. At the end of his life he was still mentally sharp and physically active.
Isn’t that what anti-aging is supposed to be? Living a long and full life. But do you have to embark on such a restrictive diet? Can’t you just take a pill or alter a gene? In the Aug. 29th issue of Cell Reports, there is an article that suggests it might be possible to alter such a gene (1). The gene in question mTOR expresses two proteins mTORC1 and mTORC2. mTOR is shorthand for “mammalian target of rapamycin”. Rapamycin is an antibiotic isolated from the soil of Easter Island and is also a powerful immune suppressor. It has been demonstrated that the earlier you give rapamycin to mice, the more you slow their aging process (2,3). In this study researchers genetically reduced the activity of mTOR gene by 75% so it was like giving rapamycin at birth. As might be expected, there was an even greater increase in overall lifespan of the mice corresponding to adding another 16 years of life to humans. These genetically altered mice also appeared to maintain their cognitive skills to a greater extent than the controls, but on the down side they also had less muscle mass and bone density. More ominously, the genetically altered mice also appeared to be more susceptible to infections in old age, suggesting that their immune systems were compromised.
OK so you get some tradeoffs by inhibiting mTOR gene expression: A longer life with greater frailty and decreased immune function as you age. Obviously, you don’t want anyone tinkering with your genes because no one knows the outcome. However, you can tweak gene expression using diet.
One way to reduce mTOR activity is to simply reduce the levels of the amino acid leucine in your diet. This is because leucine stimulates mTOR. If you stimulate mTOR, then you build bigger and stronger muscles. That’s why body builders use a lot isolated dairy protein powders that are rich in leucine as well as eat a lot of egg whites (an even richer source of leucine). On the other hand, vegans don’t eat dairy or eggs and therefore get very little dietary leucine, and their lack of muscles show it. Unfortunately, one of the biggest problems with aging is lack of muscle mass and a less than optimal immune system. So just turning down mTOR activity is probably not sufficient for healthy aging. On the other hand, calorie restriction (like that of Luigi Cornaro) stimulates another gene known as SIRT1 that causes the increased expression of the “enzyme of life” (AMP kinase) that controls metabolism and slows the aging process. You can also stimulate SIRT1 by consuming lots of polyphenols. Can’t you just fine-tune both mTOR and AMP kinase and maximize your quality of life as you age?
Of course you can by having a dietary program consisting of consuming small (but not excessive) amounts of leucine in the blood throughout the day. You can do this by eating no more high-quality protein than you can fit on the palm of your hand. This is about 3 ounces for women and 4 ounces for men. This will activate the mTOR that is necessary to build and maintain muscle and bone. By consuming large amounts of non-starchy vegetables, you are consuming polyphenols that stimulate AMP kinase. By doing both, you are constantly balancing mTOR and AMP kinase but without the rigid calorie restriction undertaken by Luigi Cornaro nearly 500 years ago. You are still restricting calories, but now in the range of 1,200 to 1,500 calories per day compared to the estimated 600 calories per day that Luigi was consuming.
Just to cover your bets since you would be consuming more leucine than Luigi did, you need to counter balance that with more polyphenols most likely by supplementation. Consuming one to two glasses of red wine per day is one way to get extra polyphenols. A better way is to use purified extracts rich in polyphenols, but without the alcohol. Finally for good measure, you want to take at least 2.5 grams of EPA and DHA as that level has been shown to increase the levels of telomeres that further decrease the rate of aging (4).
But isn’t that the Zone Diet? Of course it is, and that’s why I wrote The Anti-Aging Zone more than a decade ago. It was true then, and it is still true today.
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