An abnormal protein called amyloid might be a common thread between cardiovascular disease and Alzheimer's.

Cardiovascular disease is one of the leading causes of illness and death in aging U.S. adults, according to the American Heart Association. Alzheimer's affects about 1 in 9 Americans age 65 and older, according to the Alzheimer's Association.

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"Amyloid is an abnormal protein," said Dr. Chauncey Crandall, world-renowned cardiologist and director of preventive medicine at the Palm Beach Cardiovascular Clinic in Florida. "All of us have proteins in our body. They float around, they're soluble, they can dissolve. But sometimes something goes wrong in the system. And many of these proteins aggregate together, or they turn into clusters or islands of abnormal proteins.

"And these are called amyloid ... but these deposits can cause harm. They can deposit in the brain. And when that happens, it interrupts nerve function. It can lead to dementia, and it can lead to Alzheimer's. And also, these abnormal proteins can form in the heart, also giving disruption of heart function. So it's kind of a mixed disease. It can happen in many places. But the main concern is in the heart or the brain."

Crandall, editor of the popular newsletter Dr. Crandall's Heart Health Report, said even though this problem often can be genetic, it also can be environmental through toxicity. He said there are simple measures we can take today to prevent or reverse this problem, including diets. He suggested the Mediterranean diet, which emphasizes vegetables, fruits, and whole grains with extra virgin olive oil as the main source of fat, according to the Cleveland Clinic.

"The main thing that we can do is make sure that we have ideal body weight because we know if you're overweight, that increases inflammation," Crandall said. "You want to keep your cholesterol down because, again, that can increase inflammation. That can lead to amyloid deposition. We want to stop smoking. Anything that that we do that causes inflammation in the body can cause amyloid formation.

"So the best diet to be on is really the Mediterranean diet because that is an anti-inflammatory diet. And anti-inflammatory diets will reduce amyloid deposition."