Keep your brain sharp by steering clear of this dangerous habit.

It seems like almost every week, we're learning more about how important our lifestyle habits are for potentially preventing dementia (defined as a decline in mental ability that impacts daily life). Recently, researchers have discovered that walking three times per week, eating a berry-boosted diet and scoring more than six hours of sleep per night can make a serious impact on your brain health throughout your lifespan.

And recently, we have a new clue about dementia prevention thanks to a study published in the journal Scientific Reports. After analyzing data from more than 70,000 people between age 18 and 85 globally, scientists at the non-profit Translational Genomics Research Institute (TGen) discovered that smoking and cardiovascular disease have a direct association with cognitive function.

Both smoking and poor cardiovascular health (often triggered by factors like high blood pressure, elevated blood sugar, high cholesterol and obesity) impair the ability to learn and memorize, but at different levels depending on gender. Smoking's dangerous impacts are more pronounced among females, while males are more compromised by cardiovascular disease. In other words, to prevent dementia, one of the best things women should do? Never start smoking cigarettes—or stop smoking ASAP if you do. (Yes, we know that's much easier said than done. The CDC has a whole host of smoking cessation resources to help kickstart the process, however.)

"These results suggest that smoking and cardiovascular disease impact verbal learning and memory throughout adulthood, starting as early as age 18," said Matt Huentelman, PhD, TGen Professor of Neurogenomics and the study's senior author in a press release. "Smoking is associated with decreased learning and memory function in women, while cardiovascular disease is associated with decreased learning and memory function in men."

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Credit: Getty Images / moodboard

Besides Alzheimer's disease, the largest currently-recognized cause of cognitive decline is "vascular contributions to cognitive impairment and dementia" (VCID), which is precipitated by stroke and other vascular brain damage that affects memory and thinking ability. Smoking and cardiovascular disease heighten risk for VCID.

While the researchers are unsure why there is a gender difference, they plan to keep digging into this very important topic in hopes of saving lives and maintaining brain health. Vascular diseases are linked to elevated risk of Alzheimer's disease, which is the nation's sixth leading cause of death in America, reports the CDC.

For women who are already smoke-free, it's still important to keep tabs on cardiovascular health. Nearly all of the 13 things that could make you more likely to get Alzheimer's disease (one form of dementia) align with heart-healthy habits. According to a recent study in the journal Stroke, these include the American Heart Association's Life's Simple 7:

  1. Not smoking (sensing a theme?)
  2. Managing blood pressure
  3. Keeping healthy cholesterol levels
  4. Reducing blood sugar
  5. Increasing physical activity
  6. Eating a nutritious, balanced diet
  7. Losing weight, if needed

Rounding out the rest of the top 13 Alzheimer's prevention strategies:

  1. Preventing or treating symptoms of depression, if applicable
  2. Reducing social isolation, if applicable
  3. Limiting alcohol use
  4. Combating sleep disorders, if applicable
  5. Keeping the brain active
  6. Treating hearing loss, if applicable

Focus on those 13 things and you'll be well on your way to nurturing a healthy brain, heart and body. Seeking ways to live a longer, healthier and happier life? Discover the 1 quality that may predict which older people could live the longest.