How mental health shifts as we age – and what you can do about it

Life is about change. How we adapt to change reflects how well we live, especially as we age.

Resilience is essential for—and a sign of—healthy aging. Yet, the neurochemical, physical, and social changes that occur as we grow old decrease our resilience. This increases our risk for depression.

Have you noticed, for example, that you don't hear or taste food the way you once did? Is your sense of touch different? The senses that deliver data from the outside world weaken with age. With bad data coming in, it's hard to adjust. You grow less resilient.

Situations that feel mildly upsetting when we're 40—a drop in the stock market, divorce, moving to a new home—can feel catastrophic when we're 80. Such a high state of arousal increases the risk for cardiac disease and other potentially life-threatening conditions.

Depression as we age: understanding our biology

Changing biology—mortality, infirmities, and loss of function—dampens resilience too. Declining folate levels can cause fatigue, while arthritis and other inflammatory conditions can make moving painful. Since exercise is a natural anti-depressant, it follows that people who remain sedentary get depressed. Production of testosterone and estrogen, the hormones that give us vim and vigor, also wanes. The slight cognitive diminutions that come with age compound these changes, making us less nimble at managing stress and the vicissitudes of everyday life.

This may explain why people commonly stop caring for themselves as they age. They don't eat or sleep well, and their normal life rhythms change. Friends move away, some die, and abandonment issues rise. They start to feel like they're living in isolation, and many are. An already introverted person may isolate even more. Someone whose spouse dies after 60 years of marriage, and who has no community connection, may feel like life has shattered.

4 ways to fight depression and find resilience as we age :

Many forces push us toward depression as we age. Yet, there are many protective factors:

• Participate in meaningful, daily activity. This is the key to longevity and mental health. Having a reason to get up in the morning, either because you have to be somewhere or just need to clean your house, is important.

• Connect with friends beyond your nuclear family, or get involved in a spiritual community or something larger than yourself. These are all protectors against age-related depression.

• Find hobbies that you enjoy, like building or repairing things. These are also good for mental health and longevity, particularly after you retire. People who retire to something do very well, whereas people who retire from something to nothing do very poorly.

• Exercise. Getting your body moving everyday helps too.