Every 40 seconds, someone has a stroke in the United States, but there are ways to protect yourself from the silent killer, the nation's fifth-largest cause of death, according to Dr. Chauncey Crandall, one of America's most famed cardiologists.

"The bottom line is this: The body is amazing," Crandall, a New York Times bestselling author and director of preventive medicine at the Palm Beach Cardiovascular Clinic in Florida told Newsmax's "Newsline" Friday. "It wants to get well, but you have to take care of it." 

One way to keep yourself healthy is to have a yearly physical, Crandall said. 

"Make sure your blood pressure is under control, your cholesterol is under control, that your blood sugar is under control, that you're not overweight, that you don't smoke, and that you're doing everything you possibly can to make yourself well, the doctor said. 

"Strokes do not need to happen," he added. "We can take precautions against that. 

Crandall is the author of the runaway bestseller, "The Simple Heart Cure: The 90-Day Program to Stop and Reverse Heart Disease." The Yale-trained heart surgeon is also the editor of the popular "Dr. Crandall's Heart Health Report" newsletter. 

A stroke happens when the brain's blood supply is interrupted, preventing brain tissue from getting oxygen and nutrients. Risk factors include high blood pressure, artery disease, smoking, diabetes, and obesity.

Strokes are increasingly happening among younger people because of several factors, Crandall told Newsmax.

In the past, strokes happened when people were around age 60 and older, he said, but now people under the age of 40 are being affected. 

"Many of these people are overweight, they have borderline diabetes," Crandall said. "They have hypertension. But the other thing that sets things off a little bit is COVID."

The bottom line, though, is to stay in shape, said the doctor. 

"Let's exercise," Crandall said. "Let's eat well and make sure that you see your doctor once a year because he can intervene and prevent the things that cause stroke."

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