Andrey Fomenko, the founder of the IVAO company, conducted an interview with Brian K. Kennedy, the leading scientist- biogerontologi
What impacts human aging more: genetics or environment (food, life style, etc.)?
Most of the data indicates that aging (or at least life expectancy) is determined more by environment than genetics. Most estimates put the number around 70% environment and 30% genetics, although this varies from one study to the next and getting exact numbers is difficult. What this suggests is that it is possible to modify aging through proper lifestyle choices, and this is supported by data from human and animal studies. In short, findings sustainable strategies to incorporate exercise, a diet based on vegetables and fruits with low levels of animal protein and dairy, stress reduction and adequate sleep is generally associated with healthier aging. This can be addressed in more detail in future questions.
It should be noted that aging is likely very personalized and genetics clearly plays a role. What this means is that the ideal diet and lifestyle may differ from somewhat from one individual to the next. Moreover, what is healthy at 50 years of age may be detrimental at 80. For instance, studies indicate that low animal protein diets are associated with reduced mortality throughout most of the human lifestyle, but also that high animal diets may be protective after 70. More research needs to be conducted to fully understand the details of a healthy lifestyle and how they vary from one individual to the next.
Interestingly, in centenarians genetics seems to play a more important role as these individuals often have parents and other relatives that reach very old age. Moreover, centenarians did not tend to live healthy lifestyles throughout their younger years, although they were rarely very unhealthy. Studies are ongoing to identify the genes that confer long life in centenarians and current findings suggest that it is a combination of genes variants with small effects, although more research needs to be done.
What geroprotectors considered the most promising for increasing life expectancy?
An increasing number of interventions are being identified that extend life expectancy in animal models. These include genetic mutations, lifestyle interventions and drugs. Other approaches including stem cell therapies and medical diets are also being tested, again mostly in animal models. Interestingly many of these interventions not only extend lifespan but likely healthspan, the disease free and functional period of life. Here I will concentrate on small molecule interventions that are beginning to be considered for human trials.
One strategy to influence human aging involves nutraceuticals and a wide array already exist on the market. Most of these are relatively untested so it is a buyer beware market. There has also generally been limited testing in humans or animals, so my guess is that many do not work. However, some may actually impact aging and clear testing is needed to determine which nutraceuticals have the potential for benefit.
Several drugs have been reported to extend the lifespan animal models and a comprehensive list would include over 100 candidates. Among the most intriguing are metformin, rapamycin, acarbose and aspirin. Entire questions can be devoted to each of these. Here, I will briefly compare metformin and rapamycin. In mouse models rapamycin significantly extends lifespan, with increases of median and maximum lifespan of up to 30%. The drug is approved for human use in rare diseases, but has toxicities in the clinic, making it of questionable suitability for healthy people to slow aging. Metformin, a drug used extensively in early stage diabetes, confers smaller lifespan extension in mice, but evidence exists that type II diabetics taking metformin have surprisingly low mortality rates. Moreover, the drug is relatively safe (although no drug is completely safe) and therefore is likely to be used in the first human healthspan trials, which are being developed in the U.S. Ultimately, new drugs or a combination of drugs combined with a healthy lifestyle may have a profound effect on human aging.