Researchers say depression can increase your risk for dementia. Here’s why and some simple steps you can take to reduce the odds.

The brains of people who experience depression or anxiety may age more quickly than other people.

And researchers in a new study say this increases their odds of developing dementia.

According to the National Institute of Mental Health about 16 million adults in the United States (almost 7 percent of all American adults) had experienced at least one major depressive episode in the past year.

In addition, depression is the leading cause of disability in the United States for people ages 15 to 44.

The 2005 Harvard National Comorbidity Survey estimates that 19 percent of U.S. adults had an anxiety disorder during any given year and almost 31 percent of U.S. adults experience an anxiety disorder at some point in their lives.

“The main difference between normal anxiety and an anxiety disorder is how much it disrupts your ability to function and how long it lasts. Anxiety related to something that produces anxiety is normal, but if it persists for weeks, that may be anxiety disorder,” Dr. Gail Saltz, clinical associate professor of psychiatry at the New York Presbyterian Hospital Weill-Cornell Medical College and author of “The Power of Different: The Link Between Disorder and Genius,” told Healthline.

While earlier studies concluded that people with anxiety or depression have a significantly greater risk for dementia in later life, researchers at the University of Sussex say their study is the first to offer comprehensive evidence of the impact depression can have on overall cognitive decline.

The study, published in the journal Psychological Medicine, involved 71,000 people.

Some of the participants had symptoms of depression while others had diagnoses of clinical depression.

Researchers looked at changes in information processing and decision-making, as well as memory loss.

Participants with a dementia diagnosis at the beginning of the study were excluded from analysis to better evaluate the effect depression has on cognitive decline in the general population.

Researchers concluded that participants experiencing depression had a greater loss in cognitive ability in older adulthood than the participants without depression.

Dr. Darya Gaysina, a lecturer in psychology and lab lead at the Environment, Development, Genetics and Epigenetics in Psychology and Psychiatry (EDGE) Lab at the University of Sussex, said in a press release, “This study is of great importance — our populations are aging at a rapid rate and the number of people living with decreasing cognitive abilities and dementia is expected to grow substantially over the next thirty years.”

The Centers for Disease Control and Prevention (CDC) estimates that half of American adults will experience a mental illness such as depression or anxiety at some point in their lives.

“When you look at the number of people affected by anxiety disorders and mood disorders compared to other illnesses and you look at how disabling these disorders are in terms of loss of ability to work and lost productivity of various kinds, then it’s clear that the government is woefully underfunding resources for both research and treatment when it comes to mental health,” said Saltz.

Gaysina warns in the press release that over the next 30 years, the population of older adults will grow substantially, increasing the number of people living with impaired cognitive abilities and dementia.

She added, “Our findings should give the [British] government even more reason to take mental health issues seriously and to ensure that health provisions are properly resourced. We need to protect the mental well-being of our older adults and to provide robust support services to those experiencing depression and anxiety in order to safeguard brain function in later life.”

Mental health professionals generally agree that there are things we can do to maintain or improve our mood to stave off cognitive decline.

“It’s not inevitable that you’ll see a greater decline in cognitive abilities. Taking preventive measures such as exercising, practicing mindfulness, and undertaking recommended therapeutic treatments, such as cognitive behavioral therapy, have all been shown to be helpful in supporting well-being, which in turn may help to protect cognitive health in older age,” said Amber John, a doctoral tutor and a study author, in the press release.

According to Kristi Kincheloe, PA-C, who practices psychiatry at the Shannon Clinic in Texas, “There are many lifestyle and nonpharmacological steps that we can take to reduce anxiety and depression. Simply moving, even if it’s just walking, can fire up our endorphins and help lessen depression. Also, it’s important to cut back on sugary and high-carbohydrate foods, which may worsen depression. Research has even shown that probiotics (which encourage gut health) are an effective way to improve mood.”

Saltz emphasized, “Knowing the signs of a disorder and seeking treatment is very important. Do get an evaluation if you’re wondering. Exercising regularly will help with both anxiety and mood. Avoid recreational drugs or drinking excessively, which can make the problem worse. Make time to reflect on what you appreciate in your life. Get enough sleep, because sleep deprivation greatly affects mood. Finally, staying social and maintaining close relationships with others can help significantly.”