Age is more than just a number. That’s because scientists studying aging are moving over to a new concept of what age actually is that is more than a simple count of years on the planet. The new definition takes into account a variety of factors to better reflect that different people experience aging in different ways.
"Your true age is not just the number of years you have lived," population researcher Sergei Scherbov, of the International Institute for Applied Systems Analysis, said in a statement. "It also includes characteristics such as health, cognitive function, and disability rates."
This concept is what underlies cultural ideas of "the new 30" and the like. Someone who is 40 or older may still have the capabilities—and personality—more commonly associated with someone rather younger.
This new model does still note the physical effects of growing older The body does age, regardless of what the mind is doing; changes may occur at different rates, but they do occur. For example, as the years pass, the heart rate slows down and the blood vessels firm up. Smoking hastens this process, while a healthy diet and regular exercise can slow it down. Stress can also contribute to signs of aging, so relaxation is important. Another physical change involves bones, which become smaller and less dense. That’s why people become shorter as they get older, sometimes as early as age 30. It’s also why older people are more prone to fractures. The muscles lose some of their elasticity with age, making falls more common. This is another effect of aging that can be minimized with exercise.
Other parts subject to the general stiffening of things are the eyes and ears. In the eyes, this leads to presbyopia—literally, aged eyes. Aged eyes have trouble focusing on near objects, which is why people often need reading glasses or bifocals. Some diseases that affect vision are more common among the elderly, or at least more likely to be noticeable. Regular eye exams can help with staying on top of this. When the eardrums lose their elasticity, hearing declines, starting in the upper registers. A hearing aid can help amplify sounds and make it easier to stay in conversations. These are just some of the ways to stay young at any age.