Saturday, March 5, 2011

Don’t grow old

Last night, I watched an interesting documentary produced by the BBC called” Don’t Grow Old.” As the title implies, this program focused on various ways to slow the aging process. Among the topics discussed was using various supplements, such as resveratrol to slow aging. A leading resveratrol researcher, David Sinclair from Harvard, mentioned that resveratrol appeared to duplicate many of the effects of the only recognized method to slow the aging process, namely caloric restriction (CR). CR involves reducing daily caloric intake by a minimum of 30%. Various animal studies have shown that reducing caloric intake by 30-40% does appear to not only slow signs of aging, but also to ward off various degenerative diseases associated with aging, including both cancer and cardiovascular disease. CR is thought to work by inducing hormesis, which means by imposing stress, in this case fewer calories consumed, the body adapts by upgrading genes related to cellular protection. Among these are genes associated with decreased oxidation.

While animals exposed to decreased caloric diets do live longer, most of these animals are short-lived species. The notion that a considerable reduction of daily caloric intake can produce similar results in humans is still speculative. A few studies show that if CR added anything to human lifespan, the benefits would be modest at best, perhaps 3-7 years. If you stopped smoking, you would live an additional 10 years. On the other hand, the promotion of a lean body with decreased body fat that results from CR without a doubt does promote increased longevity. The main reason for this is probably the decreased level of overall body inflammation that comes with lower body fat levels. Inflammation tends to rise with age, and is now considered to be the cornerstone of most degenerative diseases, including cancer, cardiovascular disease, and Alzheimer’s disease. CR also helps by lowering oxidation, mainly by lowering resting metabolism.

On the BBC program, a couple who’ve used a rigourous CR program for 16 years were interviewed. Both are in their 60s, and follow a strict vegan eating routine. Both think they look much younger than their chronological ages, but the camera revealed otherwise. Both look like they are in their 60s. They do seem content, however, even if they don’t look a day younger than their actual ages. Vegan diets tend to be lower in calories due to the high fiber and water content, which is filling. But vegans also show higher rates of a process that produces advanced glycation end products or AGEs. Without getting into technical details, this process results in older looking skin. Most strict vegans often look older than their actual ages. In addition, following a CR program would be antithetical to anyone seeking added muscle. Every anabolic hormone in the body is significantly lowered on a CR regime. The same holds true for energy levels, making it difficult to exercise intensely enough to build any degree of muscle. CR also raises cortisol levels, the primary catabolic hormone in the body–not good for building muscle.

But the part of the BBC program that I found curious involved antioxidants. Two scientists interviewed on the show discussed animal studies showing that providing antioxidants did zilch to extend longevity. Not mentioned was the amount or the specific antioxidants used in the studies. I found this curious because it is well-known that built-in body antioxidants decline significantly in humans with age. Various inflammatory conditions are related to increased oxidation, including Alzheimer’s disease. The mechanism seems to be an increased activity of nuclear factor kappa-B (NFK-B). This substance is the orchestrator of inflammation in the body. What turns on NFK-B? Oxidation. So you have a scenario in aging that involves lower levels of protective antioxidants in the body, combined with higher NFK-B activity, resulting in increased overall body inflammation and all the diseases that result.

Another theory of aging discussed on the BBC program related to telomeres. Telomeres are found at the end of chromosomes, and act like strings. As you age, the telomere strings shorten. When they disappear, the cell stops replicating and cell repair ends. The cell then commits suicide. Research shows that increased oxidation speeds the shortening of telomeres. Ingesting various antioxidants, including vitamin C, slows the shortening of telomeres. All of this makes me wonder why antioxidants won’t slow the aging process. Perhaps it doesn’t in the short-lived animals in which it showed no effect. To extrapolate this finding to humans doesn’t equate to good science. In the meantime, there is one proven way to promote both endogenous antioxidant production, as well as the leanness linked to increased longevity: exercise. Indeed, some studies show that with the inclusion of regular exercise, a 10% reduction in calories provides similar benefits to the more rigorous 30% plan. It’s also more realistic for most people to exercise more while eating a bit less.

For more  the whole truth and nothing but on sports nutrition, check out my book Natural Anabolics at