You are most likely to die in the January or February, although there is an interesting blip in the data around Thanksgiving. In studies of people born during the 1800's, those born in either May or December lived the longest, while those born in February and August lived the shortest. Most people who live to be over 100 years of age tend to have lived in the same place, and around family members, for their entire lives. Are there other factors that determine how long you live?
Wealth is usually associated with longevity, however it is not obligatory. One highly consistent trend is that females outlive males; for humans it's about eight years, for spiders and rats it's about 170 days, and for beetles it's about 51 days. Female fruit flies manage to outlive the males by two days, which is astonishing given that they typically only live for 30 days. Why? One possible influence appears to be the length of telomeres on female genes. Telomeres are tails on chromosomes that gradually shorten with aging. At birth, both girls and boys have telomeres that are the same length. However, females show less telomere shortening over time. This correlation might underlie why females live longer - their genes stay active longer. However, there are many other contributing factors.
As usual, men are also their own worst enemy, and once again it's due to the presence of testosterone. However, it's not because of the crazy behaviors that this hormone induces in men. Testosterone makes men warmer due to its action upon how they metabolize food and upon how much heat their muscles produce. Lacking both testosterone and significant muscle mass, women tend to produce less body heat from their food (there are, of course, numerous exceptions to this). Numerous studies have now confirmed that having a lower body temperature prolongs life. Animals that are homeotherms (i.e. they regulate their body temperature to stay warm in a cold world) live longer if they eat fewer calories - they also become colder. Thus, being a thin female offers considerable advantages in terms of longevity.
Two different studies of Catholic nuns have demonstrated that being college educated increases lifespan by about 8 years, as compared to nuns who only finished high school. Being educated also delays the onset of symptoms of dementia associated with Alzheimer's disease; however, if you do develop this disease your mental and physical decline will be accelerated, as compared to people who develop Alzheimer's disease but did not go to college.
It is also a great idea to choose your parents carefully. Longevity is clearly an inherited trait. For example, statistical studies of long-lived families with relatives born during the 1800s indicate that if your mother lived to at least 76 years of age and your father lived to at least 74 years of age, then you have four times the probability of surviving to at least 91 years of age, as compared to people whose parents did not live so long.
In a recent blog, I discussed how obesity and aging are related. Fat dysfunction associated with obesity is now thought to reproduce many of the same metabolic conditions that underlie the aging process itself. Essentially, obesity is an accelerated form of aging and obesity predisposes us to diseases that are common in old age.
Therefore, since you cannot decide who your parents are, or which month you were born in, or your sex at birth, or how much testosterone you produce (at least not safely), all you can do is keep your brain active with learning and eat as little food as possible. Caloric restriction is the only valid, scientifically proven dietary intervention that has been shown to slow the aging process and improve health.
© Gary L.Wenk, Ph.D., author of Your Brain on Food (Oxford, 2010)
