Officially, Alzheimer’s disease is the sixth most common cause of death among Americans. But a 2014 study in the journal Neurology re-examined “cause of death” entries on death certificates and medical records, and researchers estimated that the true numbers of Alzheimer’s-related deaths are much closer to the first- and second-ranked causes: heart disease and cancer. If the numbers play out, the true impact of Alzheimer’s could be five or six times the current estimate.

But First, What is Alzheimer’s Disease?

Alzheimer’s disease is a kind of dementia—a family of brain disorders that cause deterioration of memory, decline in intellectual capacity, changes in personality, and loss of social skills severe enough to rob someone of his or her independence.

Alzheimer’s is the most common cause of dementia; it’s responsible for about 60% of all dementia cases. Alzheimer’s disease is progressive, which means it worsens as it advances. The course of the illness is generally a slow, steady slide in functioning, as brain cells degenerate and die.

If Alzheimer’s is a slide, vascular dementia—the second most common dementia—is a downward staircase, with plateaus of symptoms followed by sudden declines.

Vascular dementia is caused by damage to the network of blood vessels—the vasculature—within the brain, often from a series of small strokes due to blood clots or burst blood vessels. As the vascular system becomes damaged, blood cannot reach the brain cells and they die.

There are temporary treatments, but there is no cure for Alzheimer’s or vascular dementia. Therefore, prevention is vital. You can’t control all factors that feed into whether or not you’ll develop dementia—your genetics or age, for example—but there are many things you can do to reduce your risk. To that end, here are 4 tips for keeping your brain healthy.

Tip #1: Take Care of Your Heart and Your Brain Will Follow

According to a 2014 study from the University of Cambridge, up to one-third of all cases of Alzheimer’s are significantly influenced by lifestyle, and are therefore preventable.

So use this rule of thumb: anything good for your heart is also good for your brain. Another 2014 study followed almost 18,000 Americans for four years, and found that those with the worst cardiac health were most likely to develop cognitive impairment over the course of the study.

Furthermore, cardiac-related conditions, like high blood pressure and high cholesterol, can increase your risk of vascular dementia—so take care of your heart, and your brain will benefit.

How to do this? The biggest is exercise, which stimulates nerve growth and increases the number of small blood vessels in the brain. But getting enough sleep, eating a heart-healthy diet, and reducing negative stress are key as well.

Tip #2: Quit Smoking and Drink in Moderation (Or Not at All)

Yes, these are also lifestyle changes, but they’re so important they deserve their own tip. In a 2008 study of people over 65, those who drank more than two alcoholic drinks a day developed Alzheimer’s almost 5 years earlier than those who drank less. Those who smoked a pack a day or more got it almost two and a half years earlier. Mix heavy smoking and drinking and, on average, folks got Alzheimer’s six to seven years earlier than they would have otherwise.

Tip #3: Train Your Brain, But Not Necessarily by Staring at a Screen

In the late 1990’s, almost 3,000 older adults participated in a study where they attended ten brain-training classes which taught either memory strategies, problem solving, or quick visual reaction skills. When researchers tested them again 10 years later, the problem-solving and quick-reaction groups continued to show improvements. Only the memory group did not.

But it’s important not to misrepresent brain training as a miracle cure. Indeed, a 2013 meta-analysis—a study of studies—found that training your memory, for example, does indeed help your memory, but the effects don’t generalize to other skills.

Regardless, engaging your brain with the world is never a bad thing. And you don’t have to rely on an app or slog through puzzles as if you were taking medicine. (But if you like apps and puzzles, more power to you and your cortex!) If Sudoku’s not your style, you could take a continuing education course, try a new activity, attend concerts or plays, or simply read.

Tip #4: Ditch the Cynicism

A 2014 study found that individuals high in cynical distrust, defined as “the belief that others are selfish and manipulative,” were more likely to develop dementia than those low in cynical distrust. So reign in your judgment and give others the benefit of the doubt. You don’t have to be a Pollyanna, but to all you curmudgeons—you may wish to consider wringing out that wet blanket.

To wrap up, remember that only a portion of what contributes to Alzheimer’s is controllable. You can do everything “right” and it still might not prevent the disease. But you can control certain lifestyle choices in order to reduce your risk or delay onset—like not smoking, exercising, or rolling your eyes less often.

Finally, if someone you love has dementia, don’t blame the victim. Instead, offer support, love, and patience. If you take care of someone with dementia, my hat is off to you; be sure to seek support for yourself, too.

Again, we don’t have total control over whether or not dementia develops. But taking care of your brain now can only improve your quality of life today, as well as in the future.

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