If you eat right, exercise and take care of your heart, you may also be doing good things for your brain, a U.S. study suggests.

Researchers assessed memory, thinking and brain processing speed in more than 1,000 New York City residents and found people did much better on these tests when they had heart-healthy habits like avoiding cigarettes, maintaining a normal weight and keeping blood pressure and cholesterol in check.

"Our findings reinforce current recommendations for cardiovascular disease prevention but suggest that they may also promote cognitive health," lead study author Hannah Gardener, a neurology researcher at the University of Miami Medical School, said by email.

At the start of the study, the 1,033 participants were 72 years old on average. They all lived in Northern Manhattan, and 65 percent were Hispanic.

Researchers looked at seven factors that can contribute to better heart health: never smoking or being an ex-smoker; healthy body weight; 150 minutes a week of moderate intensity exercise; a diet rich in fruits, vegetables, whole grains and fish with little salt and sugar; and cholesterol, blood pressure and blood sugar in the ideal ranges.

None of the participants hit all seven of these goals, and only 1 percent of them achieved six. Roughly one-third of the participants managed two of these goals, and another 30 percent of them hit three of the seven.

All of them completed brain function tests at the start of the study, and 722 people did the same assessments again about six years later.

The more heart-healthy traits participants had at the beginning of the study, the better they scored on brain processing speed, or the ability to quickly perform tasks that require focused attention.

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The association was strongest for being a non-smoker, having normal blood sugar and an ideal weight, researchers report in the Journal of the American Heart Association.

By the end of the study, achieving more of the heart-healthy goals was associated with less decline over time in processing speed, memory and executive functioning.

Limitations of the study include the high dropout rate, with slightly younger participants more likely to complete both the initial and the follow-up brain health assessments, the authors note.

Even so, the findings reinforce a growing body of evidence suggesting that what's good for the heart is also good for the brain, said Dr. Jeffrey Burns, co-director of the University of Kansas Alzheimer's Disease Center in Kansas City.

"They are important findings for reminding us all the reasons why it is important to make good lifestyle choices, and that these choices have both physical and cognitive benefits," Burns, who wasn't involved in the study, said by email.

The brain, like other organs, needs a steady blood supply to function well, said Dr. Majid Fotuhi, a researcher at NeuroGrow Brain Fitness Center in McLean, Virginia, and at Johns Hopkins Medicine in Baltimore.

"Good blood flow to the brain and factors that keep our arteries healthy are critically important for maintaining and improving optimal cognitive function with aging," Fotuhi, who wasn't involved in the study, said by email.

Some previous research also suggests that smart lifestyle choices like getting plenty of exercise and eating a healthy diet might slow down the brain aging process, but the results so far aren't definitive, said Kirk Erickson, a psychology researcher at the University of Pittsburgh who wasn't involved in the study.

"In any case, there is a lot of evidence suggesting that it is never too late to start exercising, so those of us in poor cardiovascular health could still benefit from becoming more active," Erickson said by email.