Your Aging Brain

Once upon a time, you may have been taught that your brain could not create new cells. But researchers now know that brain growth actually continues throughout life. In middle age, neurons are firing most rapidly, improving complex reasoning skills and allowing us to anticipate and work out problems more effectively than in our younger years. And studies are beginning to show that brains that are even older can be trained to improve processes like verbal reasoning. You can keep your cognitive skills sharp (at any age) by doing word and math puzzles, reading, writing and even by engaging in scintillating conversations. Whether by doing so you’ll actually become smarter or just not let your brain wither away, keeping your brain active is the intelligent choice.

We all forget things, but most of these moments are normal memory blips. Age does increase forgetfulness; the hippocampus, an area of the brain crucial to memory, starts shrinking at around 55. Take that feeling when a word stalls on the tip of your tongue: everyone experiences this, but it does occur more often with age. We also lose or distort memories of facts or events over the years, because the brain purges itself of recollections to make space for new information (our most vivid memories, the ones we recall often, tend to stick around longer). Signs of actual dementia, on the other hand, may include repeating the same question or story over and over, getting lost in known places, inability to follow directions, and confusing people, time and place. These symptoms usually recur and are noticeable to the person losing the memories and to others. Memory losses like these should be evaluated by a medical professional.

Two-thirds of Americans experience some level of hearing loss by their 70s and this might be speeding up cognitive problems. A study of nearly 2,000 older adults, with hearing loss that affected conversation, showed that they were 24 percent more likely to develop cognitive decline than those with normal hearing. An earlier study by the same researchers showed an effect on dementia as well: they followed subjects for 12 to 18 years and found that those with even moderate hearing loss had three times the risk of developing dementia, compared to those with normal hearing. The good news is that aggressive treatment of hearing loss may help prevent or reduce future brain decline, so if you or a loved one is having trouble, discuss your options with a physician.

A certain amount of slowdown will happen as you grow older. Reaction time slows, and it takes longer to both learn something new and retrieve what you already know. So you may indeed make more mistakes than you used to. However, older brains are more adept at complex reasoning than they were in younger years. And studies show that the brain keeps developing throughout your life if you keep acquiring new skills. Learning to knit, to play a new game, even to use a computer in a new way helps to keep your brain active and, in the process, can boost memory and decision-making capabilities.

Scientists are finding definitive evidence that physical exercise does indeed help your brain stay fit. The Alzheimer’s Research and Prevention Foundation says regular exercise can cut your risk of developing Alzheimer’s in half because it stimulates the brain’s old connections and sparks new ones. Exercise increases blood and oxygen flow to the brain and also lowers the risk of heart disease and stroke. Running may have a particularly strong impact on brain function. Studies of animals showed those that ran on training wheels developed more new neurons than the animals that simply had visually stimulating environments in their cages. Human studies of adults running on treadmills seem to back up these findings, with runners demonstrating improved long-term and short-term memory function. Whether or not running is your exercise of choice, it seems that starting a regular fitness routine in midlife is particularly helpful in staving off dementia and other brain decline.

You’ve probably heard of the heart-healthy Mediterranean and DASH (Dietary Approaches to Stop Hypertension) diets, but you might not know these habits may also protect your brain. Foods can contribute to inflammation and insulin resistance, which can damage the neurons responsible for communicating within the brain. There’s evidence that diabetes might be linked with Alzheimer’s in some way; in fact, the disease is sometimes called “diabetes of the brain.” To help prevent or reduce this inflammatory response, follow a diet high in vegetables and fruits, low-fat dairy, whole grains, fish and poultry, nuts and olive oil. For best results, cook at home with whole ingredients instead of packaged, processed foods. Cut way back on red meat, sugar, refined carbohydrates and trans fats. Some research shows that green tea and omega-3 fats might also help. And, of course, consume alcohol in moderation and don’t smoke.

It’s possible that B12 supplements might indeed give your brain a boost. B12, which we get from eating fish, meat, eggs and dairy, needs stomach acid for absorption, and it’s not uncommon for that acid to decrease as we age. A shortage of B12 can contribute to dementia, mental impairment, depression, muscle weakness and fatigue. Older adults living in nursing homes are one group at particularly high risk for B12 deficiency due to limited diets. The good news is, adding B12 to your diet can directly improve early symptoms of deficiency. Once you hit 50 (or if you’re a vegetarian or have health issues that might prevent nutritive absorption), the National Academy of Medicine recommends eating foods fortified with B12 or taking a multivitamin to get your daily requirement of 2.4 micrograms.

But the jury is still out on whether you’re better off being overweight or underweight when it comes to this particular issue. A study of 2 million people published in 2015 surprised the medical community: results showed obese and overweight people were 30 percent less likely than those of normal weight to develop dementia. Being underweight, on the other hand, raised the risk of dementia by 34 percent. Researchers immediately cautioned people not to gain weight to stave off dementia and said much more study is needed, but these results could point to new directions for treatment and prevention of Alzheimer’s and dementia. In the meantime, other studies show that obesity not only increases your risk of stroke, but there may be a correlation between being morbidly obese and increased brain atrophy as you age. For now, it seems that maintaining a healthy weight is the safest bet.

A Dutch study did find that loneliness increases an older person’s risk of dementia by 64 percent, but living alone wasn’t necessarily the problem; the risk came with feeling alone—having no one who cares about you. Loneliness plays a role in depression, which has been linked with dementia (one study showed that nearly 40 percent of people who developed Alzheimer’s also had depression), though scientists are still trying to discover if depression somehow changes the brain. They do know that both depression and the risk of dementia are reduced by social activity. What is important is finding and maintaining friendships with people who care about your well-being. Join a club, sign up for an exercise class or a bowling league, walk with a friend, volunteer for a charity organization, become a reader at a local school or library or have weekly dinners with a neighbor. Even steady contact with people by phone or Facetime can help alleviate loneliness.

Studies show just the opposite for many people. After a dip in happiness from early adulthood through the 40s, the 50s and 60s often bring an upswing in mood. This “happiness U-curve” might impact not just how much you enjoy your later years but how long you live; a British study of 9,000 people in their 60s found that the happiest subjects lived longer than those least content with their lives. Research still hasn’t shown exactly what turns a person’s happiness around with age but similar findings among apes suggest that frontal lobe deterioration could play a role. That sounds scary, but in this case, reduced function in that part of the brain means older people don’t process bad news as negatively as they did when they were younger. This can help you keep a positive outlook—and research suggests that optimists live longer. So it really might pay off to keep an eye on the bright side of life even as you check off those birthdays.