More than 700,000 people suffer from strokes every year, according to National Institute of Neurological Disorders and Stroke.
Forty-year-old Brian Fender was one of them — but he didn't even know it.
"I couldn't speak correctly," he said. "I knew what I wanted to say, but I couldn't. It just came out as gobbly-gook."
Three months ago, Fender injured his neck at the gym when he was working out on the incline bench. He felt disoriented, so he decided to see his primary care physician who referred him to Carolyn Brockington, director of the Stroke Prevention Program at St. Luke’s-Roosevelt Hospital in New York City.
"A stroke is really caused from an interruption of blood flow to the brain over a period of time," Brockington told FOXNews.com. "This actually causes a permanent injury to the brain, so that part of the brain has actually died from not having sufficient blood flow."
After undergoing an MRI, Brockington discovered he had injured an artery that supplies blood to his brain.
And even though the brain can't regenerate itself — stroke victims still can recover, she said.
"The area that surrounds the injury is still normal, and hopefully it will make connections with itself and take over what that part of the brain did," Brockington said.
Brockington said a stroke can be preventable by watching out for these symptoms:
— Weakness or numbness in hands, legs and face especially on one side of the body
— Trouble seeing, walking or speaking
If these symptoms come on suddenly — you should go to the emergency room right away, Brockington said.
"For some strokes, we're actually able to give a medicine that’s called TPA, that’s essentially a clot-buster," she added. "It allows blood to get back into the brain ... but we're very limited in terms of the time. It's three hours since the symptom onset."
Studies have shown that 33 to 50 percent of people who get TPA have minimal or no effects after having a stroke.
Anyone can have a stroke, but if you are a smoker, have high blood pressure, diabetes and/or high cholesterol, your chances are increased.
"If you ever experience yourself trying to say something, and it comes out as gibberish, go see a neurologist immediately," Fender added.