During and after midlife, many questions rolled through my head. I recall a conversation with my dad many years ago. We were lamenting the fact that my maternal grandmother had been diagnosed with Alzheimer’s and was in a slow mental decline.
My dad said, “and that will happen to you years earlier than it did to her.“
I remember that statement so vividly because it bothered me for him to pronounce such a negative declaration about my future health. He was basing his opinion solely on his belief that I had inherited every bad and rare gene that my ancestors had to pass down!
In his mind, clearly, if my grandmother had Alzheimer’s, I was doomed to the same fate.
Is that true?? Am I fated to spend my last ten years in a nursing home unable to even feed myself, I wondered.
Since that conversation, I’ve spent some time thinking about what an important role lifestyle and environmental factors play in one’s health and lifespan.
Could I live a long life in spite of my family tree? I was determined to live a healthy lifestyle. Would it help to find out as much as I could about the genetics of aging in my ancestry?
What Determines Life Expectancy?
By studying the effect of genetic variations on lifespan across the human genome, scientists are able to determine the probability that you will live an average lifespan or if you have the potential for exceptional longevity.
Most scientists who study gerontology are divided on how much of our lifespan is determined by genetics. Some say the heritability of lifespan is well under 7%. Family studies demonstrated that about 25% of the variation in human longevity is due to genetic factors.
A safe estimate is that your genes play a small role, perhaps between 7-30 percent, in how long you will live.
You can find out more with genetic testing; a test that reveals which genetic variants you have inherited. Genetic Data can reveal genes related to cardiovascular disease, balding, and many other traits.
If you find out you do have the genetic variation for a particular disease, you can alter your lifestyle to turn off that gene expression.
Researchers found that the gene sirtuin 6 (SIRT6) is responsible for more efficient DNA repair in species with longer lifespans. The research illuminates new targets for anti-aging interventions and could help prevent age-related diseases.
The Old Nurture vs. Nature Debate
So is the answer to longevity in your genes or your environment?
The human life span goes through many changes, but it appears that lifestyle has contributed to longevity in the last century. Throughout your life, genes may be turned off and on. This process is known as methylation. When this happens, the gene still exists, but it can’t be read.
This is why knowing your genes can be beneficial. Turning off a certain gene may prevent that genetic expression which could, in turn, reduce the risk of a particular disease. In other words, your genes don’t have to be your destiny.
Knowing Your Genetic Variants
I used self decode testing to not only find out more about my genomics but also how to use that information to improve my odds of living a longer life.
Interestingly, some of the gene variants that determine if you will live a long life have a lot to do with your mitochondria (your body’s cells.) Cell function includes the maintenance of something called telomeres (the tip of a chromosome) and DNA repair, as well as protection of cells by free radicals. Some of the genes associated with longevity are also connected with inflammation, cardiovascular, and immune function.
The results I received gave me the information I was looking for about my genes, but it also came with more health care recommendations. Because I am fascinated with health and longevity, I’d already been practicing many of the suggestions. Others were new to me.
Overall, I was able to make changes that I hope will help me lengthen my healthspan as well as my lifespan.
Because when we search, “is life expectancy genetic?” What we really wanna know is, “can you increase your lifespan?”
Most of us want to live a long healthy life.
Lifespan vs. Health Span
Celebrated supercentenarians have been interviewed to determine the secrets to living to 100 and beyond. Why? Because we’re looking for something we can do to extend our own lives!
Long life is more fun if you experience healthy aging. However, if, like my grandma, I live to 90 only to spend my last ten years in a nursing home unable to communicate or do anything else. Well, I’m not sure I would want to live a longer life.
I’d like to live the maximum lifespan that I am able to with good health while caring for my basic needs. I think most of us do not want to end up like that in our older age.
How to Live Longer and Be Healthier in Old Age
It’s not too late to get started living a healthier lifestyle. You’re probably already aware of the changes you need to make. Here are a few common ones:
- Don’t smoke – smoking accelerates the aging process and can lead to heart disease.
- Maintain a healthy weight which reduces your chance of type 2 diabetes, high blood pressure, and other diseases.
- Exercise reduces your risk of dying before age 90 by about 20%
- Eat more vegetables and leafy greens.
According to the author of Lifespan: Why We Age―and Why We Don’t Have To, one of the biggest threats to humanity is an infectious disease to which a vaccine cannot be produced quickly enough. Hmmm. Not sure what I think about that prediction! (The book was published in 2019.)
Still a great read for anyone interested in extending lifespan. I particularly enjoyed Chapter 9 and the conclusion where the author talks about what he and his father do to live longer, healthier lives. “What I do – eat fewer calories, don’t sweat the small stuff, and exercise.” He also goes into detail about what supplements he takes and what kind of diet he follows. Says he gave up desserts at 40 but still has a taste here and there.
Although parts of it can be a bit dry, I did enjoy the conversations the authors have in between the chapter readings. It’s worth a listen, even if you skip parts!
Passarino, Giuseppe et al. “Human longevity: Genetics or Lifestyle? It takes two to tango.” Immunity & ageing : I & A vol. 13 12. 5 Apr. 2016, doi:10.1186/s12979-016-0066-z
A.M. Herskind, M. McGue, N.V. Holm, T.I. Sorensen, B. Harvald, J.W. VaupelThe heritability of human longevity: a population-based study of 2872 Danish twin studies pairs born 1870–1900Hum. Genet., 97 (1996), pp. 319-323