Healthspan: More than just Lifespan
Imagine what it would be like to live to an incredibly old age but have no meaningful use of your body, no ability to interact with your loved ones, and no capacity to enjoy life. Probably sounds like a terrible existence. Yet, this scenario is all-too-common as modern health care has found ways to keep the human body alive even though it is no longer functional. It’s akin to an automobile that doesn’t run but still looks like an automobile just because its body is intact.
What is Healthspan?
Instead of focusing solely on lifespan, the time spent alive, it would behoove us to think more in terms of healthspan. Healthspan is the period of life spent in good health, free from the chronic diseases and disabilities of aging.
One framework for explaining healthspan is to think of it in terms of 4 critical components:
- Mind (cognition). We readily recognize the value of an elderly individual having a brain that is “sharp as a tack”, standing out in stark contrast to those who suffer cognitive impairment. With neurodegenerative diseases, short-term memory is often the first noticeable deficit. Loss of cognitive function then progresses to impair executive function – being able to concentrate and pay attention – in later stages of dementia.
- Body (physical function). A body that performs as it is intended is remarkably valuable for interacting with the world, and the independence that comes from having a functional body is highly valued. It is important to maintain muscle and functional movement. Muscle is vital for structural reasons (balance, fall prevention, etc.) as well as metabolic reasons. It’s also incredibly important to maintain mobility of the body, particularly in the spine and hips.
- Freedom from pain. While pain is a vital sensation for self-preservation and protection from harm, uncontrollable pain can be all-consuming and be associated with impaired mental health. Chronic pain and its management can both take a huge toll on quality of life.
- Stress tolerance. It is inevitable that we will encounter stressors in our environment on a regular basis and of variable severity. Resilience to stressful events, whether physical or emotional, is essential to remaining functional.We expect to see a decline in each of these areas as we age. Our goal should be then to decrease the age-related decline in these areas, such that the period of morbidity (unhealthy functioning) is minimized.
What can we learn from centenarians?
First, we learn that genetics are certainly a factor. Genetics have consistently been found to be relevant to nearly all recognized disease processes, as well as to the simple physical changes associated with aging. Genes can even be turned on or turned off from generation to generation depending on behavioral and environmental factors, a fascinating field of science referred to as epigenetics. While epigenetics explains how we can influence the health of future generations, there’s only so much that we can do to override our own genetic makeup.
Second, we gain insight from the ways that people tend to die. When looking at how individuals over the age of 40 die, excluding suicide and smoking-related disease, 80% will die from one of the following 4 processes:
- Cardiovascular/cerebrovascular disease – heart attack, stroke, etc.
- Neurodegenerative disease – dementia, etc.
- Accidental death
For centenarians, individuals who live into their 100’s, the trends appear similar but with some differences:
- More from cardiovascular/cerebrovascular disease
- Less from cancer
- Same for neurodegenerative disease
- More from pneumonia
The major causes of death are quite similar between individuals who live 40 – 99 years and those who live to at least 100. Ultimately, the major difference is that centenarians develop these disease processes later in life. Thus, one potential strategy for longevity is to delay the onset of chronic disease.
Steps to increase healthspan (and possibly lifespan)
- Eat nutritious foods; avoid highly processed foods
- Control glucose – optimal being less than 85 mg/dL, with minimal variability (less than 15 mg/dL in either direction)
- Intermittent Fasting, with compressed eating windows – beneficial due to both calorie restriction and encouraging autophagy
- Maintain/develop muscle mass – significant implications for metabolic health, including being a buffer/sink for glucose. In a study of individuals with pre-diabetes, muscle biopsies showed that the greatest predictor of developing type 2 diabetes was insulin resistance in the muscles. Strength training is important to maintain insulin sensitivity.
- Decrease inflammation
- Learn healthy ways to manage stress
- Ensure high quality sleep, which is important for hormones, brain health, and metabolism.
Quality over Quantity
Each of these steps deserves a separate discussion, but this list gives you an idea of the range of lifestyle modifications that appear to be strong contributing factors to healthspan.
The point is not just to survive, but rather to thrive. Another way to think about it: Add life to your years, not just years to your life. It’s not enough just to stay alive for a long time.
Life expectancy and lifespan don’t guarantee the future you want, as there’s more to just spending a long time on this earth – make sure it’s quality time.