8 Surprising Habits That Harm Your Brain Health

We all want to stay sharp as we age. But unhealthy choices and unintentional missteps could be messing with your brain health.

Here, Rahul Jandial, MD,PhD, an LA-based neurosurgeon-scientist and author of ​Life on a Knife's Edge​, shares which harmful habits are hampering your brainpower, plus tips to keep your cognitive function in fighting shape.

Sitting all day is detrimental to your overall health. And your brain is no exception. "Sitting is inactivity, and inactivity is bad for the brain," Dr. Jandial says.

That's because movement "keeps the brain arteries open, allowing the delicate neurons to stay irrigated with nourishing blood," he explains. In other words, physical activity boosts blood flow and, in turn, transports oxygen and essential nutrients to the brain.

Plus, it improves mood and reduces stress, which are both beneficial for brain health. So, when you sit on your bum a lot, your brain isn't reaping the benefits.

"While some people thrive on solitude, most do not," Dr. Jandial says. And skipping opportunities to be social may be sabotaging your brain.

"Loneliness is linked to depression," Dr. Jandial says. And it can also play a role in cognitive decline.

Case in point: An October 2020 study in ​The Journals of Gerontology: Series B​ found that less socially active people exhibited a greater loss of gray matter integrity in specific regions of the brain relevant to the development of dementia.

Believe it or not, blasting your headphones might be harming your brain.

Indeed, extended exposure to loud noise can change how the brain processes speech, according to a small animal study in the November/December 2014 issue of ​Ear and Hearing​. The researchers noted that noise-induced hearing loss may affect the brain's recognition of speech sounds.

While this research was done in animals, it may have important implications for humans as well. That's because hearing loss over time has been linked to dementia, Dr. Jandial says.

A whopping third of American adults don't get the recommended seven hours of sleep, according to the Centers for Disease Control and Prevention (CDC).

But when you don't log enough pillow time, it taxes your brain.

In fact, a September 2018 study in ​​Sleep​​​​ concluded that cognitive performance — including memory, reasoning, problem-solving and communications skills — is impaired in people who usually sleep fewer than seven or more than eight hours per night.

From cancer to heart disease and lung-related illnesses, smoking ravages virtually every organ of the body. And you can add your brain to that list.

"Smoking damages the lining of blood vessels and can lead to narrowing, which can cause reduced blood flow to the brain," Dr. Jandial says.

Again, the less oxygenated blood that bathes your brain, the fewer fundamental nutrients it receives.

Hate to break it to you: Your sweet tooth could have a negative effect on your noggin.

Research in animals demonstrates a link between sugar consumption and the aging of cells and deficiencies in memory and cognition, according to Harvard Medical School.

And in humans, you can clearly see the consequence of excessive sugar on the brains of people with diabetes, a disease characterized by chronically high blood glucose levels. High blood sugar can affect the brain's functional connectivity, shrink the brain or cause small-vessel disease, which inhibits blood flow in the brain, leading to cognitive difficulties, per Harvard Medical School.

Sprinkling too much salt on your food isn't in your brain's best interest.

Excessive sodium is associated with health problems like high blood pressure. And the effects of chronic hypertension include reduced blood flow to the brain, making your brain more vulnerable to atrophy and cognitive impairment, according to a June 2014 ​Neurology​ study.

Your frequent happy hour habit might be hindering your brain health. In addition to temporary effects like blurred vision, slurred speech and slowed reaction times, heavy drinking can increase your risk of developing more serious, permanent changes in the brain, according to the National Institute on Alcohol Abuse and Alcoholism (NIAAA).

Indeed, long–term heavy alcohol use may shrink the brain and cause deficiencies in the brain's white matter, the fibers that transport information between the gray matter, per the NIAAA.