Brenda Black has a passion for art, and the canvas, paintbrushes, and color soothes her soul. Fruits and vegetables fuel her body. 

The 54-year-old has spent decades reducing stress. Eating right, working out, but one day something felt wrong.

“I was running, and all of a sudden I felt this real heavy feeling on my chest, almost like someone was stepping on my chest,” said Black.

Black's husband took her to the hospital.  She had a heart attack.

“They said there was blockage, but didn’t attribute it to anything in particular,” said Black.

Researchers at Johns Hopkins University have found evidence that plaque buildup in the heart may be coming from an unexpected source: over the counter calcium supplements.

The researchers studied 10 years worth of medical information for 2,700 patients, including scans of the heart arteries.

“We found those who were taking supplements, calcium supplements compared to non-supplement users were 22 percent more likely to have new development of calcium on heart arteries on the second cat scans ten years apart,” said Dr. Erin Michos, a cardiologist at Johns Hopkins. 

The research also indicated that dietary calcium might have a positive impact on heart health. Michos says for some patients with differing calcium needs, the low-dose supplements may be helpful. But even though they are available without a prescription, she recommends people consult with their doctor before taking them.

Black was not part of the Johns Hopkins study but had been taking supplements for about two years.

“I kind of increased it in the last year where I thought maybe more was better for me, because I’m not getting calcium.  At least not as much as I should,” said Black.

“I think that patients think because these are over the counter that they’re safe, and more is better,” said Michos.

Instead, experts advise patients to get more calcium from their diets.

“Green leafy vegetables are a great source. They’re almost equivalent to a lot of dairy products,” said Kelly Alagna, a cardiac nurse at Johns Hopkins.

Kale, spinach, bok choy, broccoli, and Brussel sprouts are good non-dairy sources of calcium.

Black is getting stronger every day, and she has sworn off the daily pills and chews she used to favor. She says if calcium supplements are causing blockage then the word needs to get out.