From time immemorial, humankind has been searching for the fountain of youth, and we are still looking today. In our scientific age, this search has focused on the question, “Why do we age?” For decades, scientists have been studying the subject. There are currently more than 300 theories on why we age, and experts are learning more every day.
In its broadest sense, aging merely refers to the changes that occur during an organisms’ lifespan, though the rate at which these take place varies widely. Aging is likely caused by a combination of factors. Intrinsic aging is a genetically predetermined process that occurs naturally. Extrinsic aging is a result of outside factors determined by where you live, your stress levels, and your lifestyle habits, like exercise. (The former you can’t do anything about but the latter you can.)
One theory of intrinsic aging, referred to as programmed aging, suggests our body’s cells have a predetermined lifespan that’s encoded into our bodies. This theory says people are designed to age and that our cells have a predetermined lifespan. Included in the intrinsic theories of aging, gene theory suggests that specific genes turn “on” and “off” over time, endocrine theory suggests aging is caused by changes in hormones, and immunological theory is the idea that the immune response is designed to decline, resulting in disease and aging.
Among the more well-established extrinsic theories of aging are the genome instability theory, in which aging happens because the body loses its ability to repair DNA damage that occurs over time, and the free radical theory. This theory states that aging is due to the buildup of oxidative stress, which is caused by free radicals. Free radicals are oxygen-containing molecules that can cause certain chemical reactions in your body called oxidation, and this can be beneficial or harmful. This is the basis of “anti-aging” drugs which claim to be antioxidants.
So, what about that fountain of youth? It isn’t found in a pill or a potion, and there’s lots of “anti-aging” snake oil out there. The best medical science tells us that aging can’t be delayed but the effects of aging can. Here’s how to slow aging: 1) Eat a nutritious diet, with focus on fruits, vegetables, whole grains, and lean protein and limit processed foods, 2) Stay active because exercise reduces the physical and mental effects of aging, 3) avoid tobacco – a health provider can help create a cessation plan that works if you smoke, 4) drink alcohol in moderation or not at all, 5) get regular checkups (your annual Medicare Wellness Visit if you are > 65) because routine checkups with a doctor are the best way to prevent or treat disease early and 6) engage your brain–protect your cognitive function by practicing brain health.
Many of the things we associate with getting older—loss of function and disease—are hard to accept and have become the stereotype of what it means to get older. However, remember this. Aging is not a disease and as we’re living longer and often healthier lives, many areas improve as we age. Greater sense of acceptance of self and of others; desire for connection and the means to create it; life experiences that help us make smart decisions; wisdom and empathy—all are available to us as we grow older.
(Parts of the above adapted from “Why Do We Age?” by Kristen Nunez, Healthline, March 23, 2021, https://www.healthline.com/health/why-do-we-age.)
Dr. Scott is UGA associate professor of medicine, director of geriatric medicine education at the AU/UGA medical Partnership, and medical director of the C.A.R.E Clinic. Have a question for Dr. Scott? Email him at athensgeriatrician@gmail.com.
