The Secret to a Healthy Brain? Start Taking Care of Your Heart

  If it seems that there are more people with dementia than there used to be, it’s not your imagination.  

Right now 6.5 million Americans ages 65 and older are living with it, and by 2050 that number is projected to have risen to 12.7 million, according to the Alzheimer’s Association. A big reason: the state of our heart health.

The brain requires fuel to function, and it gets its fill when the heart pumps lots of oxygen and glucose-containing blood upward, says Constantino Iadecola, M.D., director of the Feil Family Brain and Mind Research Institute at Weill Cornell Medicine. But the brain doesn’t have any reserves of this crucial resource. Consider your heart and blood vessels as supply lines to a remote city with no grain silo, Dr. Iadecola says. “If the tracks don’t work, the city doesn’t eat and the people starve.” The lifestyle factors that keep your heart in good shape are the same ones that may dramatically lower your risk of brain-health issues as you age. Though there is no cure for dementia, “taking steps to prevent heart disease, which we do know how to do, can have a big impact on cognitive disorders,” explains Rebecca Gottesman, M.D., Ph.D., senior investigator and stroke branch chief at the National Institute of Neurological Disorders and Stroke.In fact, your cardiovascular fitness may be the most important factor in keeping your mind sharp for the long haul. The evidence overwhelmingly supports this notion: In a study from Finland, people with the best cardiovascular scores at midlife cut their risk of developing dementia later in life by up to 40% compared with those who had the worst scores. In another study, Swedish researchers found that the more quickly people developed cardiovascular risk factors, the more likely they were to experience Alzheimer’s and dementia.But this is not just an older-person issue: One study on heart-healthy habits—this time in young adults—showed that those who practiced more of these positive actions had fewer changes to the blood vessels in their brains, a measure of dementia risk. Essentially, the better shape you’re in early on, the younger your brain age will be in the future, according to another study. “What you do when you’re young is extremely important,” says Dr. Gottesman, perhaps even more so than taking charge of risk factors later in life. Read on to see what we’re learning about the ways your heart helps your head (and vice versa) and how you can use this new knowledge to stay healthy.

How the heart and brain are so closely connected

A scary stat: About half of us have one or more of the big three heart disease risk factors—high blood pressure, high cholesterol, and a smoking habit—according to the Centers for Disease Control and Prevention. Here’s how that could impact your brain.

Blocked arteries can lead to stroke

Healthy arteries normally are elastic and let blood flow freely. If they stiffen, the heart pushes harder to get blood through, adding pressure—that’s high blood pressure, a.k.a. hypertension. If a vessel supplying the brain gets completely clogged and blood can’t pass through, a stroke can follow, and brain cells may starve. “It’s an immediate process,” Dr. Iadecola says. “The fuel the brain needs to get the neurons to fire and communicate isn’t there, and the neurons stop talking to each other and eventually die.” Depending on what part of the brain is deprived of nutrients, stroke victims may lose speech, clearheadedness, ordinary emotional reactions, or the ability to move smoothly.

Poor heart health can contribute to dementia

Dementia can happen when the brain doesn’t get enough blood because of clogged or damaged arteries or because the heart is weak. “Every minute the brain doesn’t get enough blood, cognitive function is impaired,” says Dr. Iadecola. If cardiovascular health improves, cognitive function can too. “But if blood levels are even marginally reduced for months or years, certain areas of the brain are susceptible to permanent damage,” he adds. Depending on which region is affected, it may take longer to do a calculation or be impossible to make a decision when faced with complex choices. Vascular issues can also contribute to Alzheimer’s disease.

Blood flow can affect Parkinson’s

A variety of things can cause Parkinson’s, which is characterized by loss of muscle control, rigidity, and tremors. “In some cases the symptoms may be due to insufficient blood flow to the areas of the brain that support muscular coordination, posture, and the ability to walk,” says Dr. Iadecola.

Diabetes affects both the heart and brain

While diabetes is not considered a heart problem per se, “people with diabetes are twice as likely to develop Alzheimer’s disease,” Dr. Gottesman says. Why? Excess glucose can affect the connectivity between regions of the brain, eventually leading to cognitive difficulties. High glucose levels can also damage blood vessels, leading to heart attack or stroke.

3 habits that improve heart and brain health

You’ll get double the benefits from these healthy habits. A recent study found that 65-year-old women with four or five healthy factors (such as healthy diet, engaging in physical activity, doing cognitive tasks, not smoking, and limiting alcohol) had a life expectancy of 24.2 years—3.1 years longer than those with zero healthy factors or only one.

Eating a Mediterranean diet

People who follow the Mediterranean diet (or come close to it) have significantly less heart and Alzheimer’s disease and fewer strokes. It may also help with diabetes. Here are some of the best foods for heart health:

• Fruits and vegetables
• Whole grains and nuts
• Legumes (beans, peas, lentils)
• Salmon and other fish high in omega-3s at least twice a week
• Healthy fats, particularly olive oil
• Wine in moderation
• Minimal red meat, processed foods, sugary drinks, and sodium

Doing cardio workouts

Numerous studies have shown that exercise makes arteries less stiff. Aim for 150 minutes a week of moderate exercise, like brisk walking or recreational swimming. If you step up the intensity—for example, by running or playing singles tennis—around 75 minutes per week is enough (though more is better). Strength training may also help control blood pressure.

Prioritizing relaxation

Daily deep breathing and/or meditation lets the brain and the heart relax, which is restorative for the entire body. “It’s very important to self-regulate your blood pressure,” says Ravi Dave, M.D., of UCLA Health. Count down from 10, breathing in on 10, out on 9, in on 8, and so on, saying the numbers as you go. Or try meditation: It’s been found to lower blood pressure, reduce cardiovascular mortality, improve diabetes, and more. If you’re new to it, try an app like Headspace or Calm. Be sure to get enough sleep as well.

How your mind affects your heart

Your physical health and your mental health are part of the same system and have the same goal (to keep you going). So if something on the emotional side of things goes awry, that can lead to physical problems. Consider these three common emotional reactions and their effects on our hearts.

Stress

“Constant anxiety can create lasting damage,” says Dr. Dave. Chronic stress can impede blood flow in the coronary artery, leading to cardiac events. It has also been linked to inflammation, which can cause clogged arteries and other problems.

Depression

Many factors may contribute to depression, but researchers believe that both a neurological chemical imbalance and a malfunctioning of the brain’s mood-regulation ability are involved. This interferes with blood circulation and promotes inflammation, says Dr. Gottesman.

Shock

Sudden and profound sadness or trauma can lead to a “broken heart” (called Takotsubo cardio myopathy). “A surge of negative hormones causes the heart to stop functioning temporarily,” says Dr. Dave, but it’s rarely fatal.