Living longer and living more years looking and feeling youthful and disease-free are not one and the same. Although our life expectancies are getting longer, people are also spending more years with age-related chronic diseases. That is to say, we are not necessarily getting more years of vitality and good health but instead are getting to experience more years of illness.
With major advances in sequencing technologies and analytical algorithms, the ability to define aging and longevity separately has become possible only in recent years. These definitions are essential for improving aging and longevity and living longer lives filled with lots of energy and good health.
Know thy enemy, and know thyself
One way to think about aging and longevity is in terms of healthspan and lifespan, respectively:
- Healthspan: the part of a person’s life during which they are generally in good health.
- Lifespan: the time a person or animal lives.
With these concepts in mind, the scientific community has come up with some general definitions for aging and longevity, which can be roughly stated as the following:
- Aging: the progressive, event-dependent decline in the ability to maintain biochemical and physiological function.
- Longevity: the length of the lifespan.
Now, just because these two concepts are different doesn’t mean they are not intertwined. Distinguishing human biological aging from longevity can be difficult because the rate of aging may affect the length of the lifespan. With that being said, some researchers argue that lifespan and longevity are independent of healthspan and aging. That is to say, there are different forces at play.