Your Brain Health After 50

Your risk of developing dementia is lower than that of previous generations, thanks to healthier living. But if you're concerned about your brain health in your 70s and 80s, there are steps you can take now to start protecting it.

When I have “senior moments,” are these early signs of dementia?

Probably not. “It's important to understand the difference between the earliest stages of Alzheimer's and normal cognitive aging,” says neurologist Richard Isaacson, director of the Alzheimer's Prevention Clinic at Weill Cornell Medicine and New York-Presbyterian. “Just like our skin wrinkles, our brains age, too. Age-related cognitive decline shows in things like a word that's on the tip of your tongue and you remember it later. With Alzheimer's, you'll forget the word and it'll never come back. If you forget your keys and realize you were doing three things at once, that's no big deal. But if you lose your keys and you can never find them, and it's happened three or four times, it's time to get screened."

I want to eat more fish, but I'm worried about mercury affecting my brain. Is it safe?

Yes. In fact, “it's likely that eating fish regularly as part of a balanced diet could reduce your risk of age-related cognitive decline,” according to the U.K.'s Alzheimer's Society. If you're a drinker, however, you might want to be careful. Recent studies have shown a link between elevated mercury in the body and reduced liver function in older adults, particularly those who drink alcohol regularly. If you're still concerned, the Food and Drug Administration (FDA) lists shark, swordfish, king mackerel and tilefish as high in mercury. Shrimp, canned light tuna, salmon and pollack are lower, and safer, by comparison.

I wake up in the morning tired and irritable. Is this normal?

Bad sleep and bad moods can be a bad sign. A 2019 study in Science Translational Medicine showed that older adults who have less slow-wave sleep — the deep slumber that consolidates memories — have higher levels of the brain protein tau, which is linked to cognitive decline and Alzheimer's. Waking up tired and irritable on a regular basis could be a red flag that you're shifting from healthy to impaired brain function. So could general crankiness: A 2019 Danish study of 6,800 people found that those who are distressed in late midlife (average age: 60 in the study) may be at a higher risk for dementia later on. Researchers call it vital exhaustion, a state of prolonged stress that causes symptoms like unusual fatigue, irritability and demoralized feelings. Don't wait for it to get worse.

Should I be tested for the Alzheimer's gene?

Probably not. You can order an FDA-approved commercial test for APOE — the Alzheimer's risk gene — from websites such as 23andMe ($199). And you'll no doubt scare yourself silly if it comes back positive. In reality, though, it doesn't mean very much. “The APOE risk gene is not a diagnostic gene,” Isaacson explains. “If you have it, you don't necessarily get Alzheimer's. If you don't have it, you can absolutely get Alzheimer's.” That said, Isaacson orders the APOE test for his patients anyway because, he says, “knowledge is power. Knowing you have a gene that increases your risk, along with any family risk, might make you more likely to exercise and eat right,” the two biggest brain-health weapons within your control.