Delving into the dangers of diet soda: Why even moderate consumption can affect your heart

If you enjoy diet soda, a recent study may have caught your attention.

Drinking just even one regular serving a day could lead to an irregular heartbeat, which can be dangerous.

What is it about diet soda that can damage your heart?

The fizzy sound of diet soda is music to Donna Gross' ears.

"I drink diet Dr. Pepper and I drink about seven a week," she said.

Seven cans a week may seem moderate but a study in the journal Circulation found drinking that amount and more could increase your risk for atrial fibrillation 20% compared to people who drank none.

"I used to drink a lot and I could tell my heart was beating fast," said Avedis Aladzhyan in Calabasas.

"Atrial fibrillation is gonna be an arrhythmia. What are arrhythmias? These are unwanted heartbeats," said pulmonary critical care specialist Dr. Raj Dasgupta.

He said atrial fibrillation or A-fib is a dangerous condition on the rise in the U.S. Experts predict cases will double from 6 million Americans this year to 12 million in 2030.

"Blood will stagnate in the atria, and it puts you at risk for things like stroke. You could have acute shortness of breath. You could have horrible palpitations," he said.

So what is it about diet soda that causes an irregular heartbeat? The research is still preliminary but researchers say it may have something to do with the artificial sweetener itself.

"Something is irritating the heart," Dasgupta said.

He compares too much diet soda consumption to what can happen when people drink too much alcohol.

"We know that some of the breakdown of alcohol is directly toxic to the heart. Consuming certain products may contain things that can be an irritant that can cause you to go into A-fib," he said.

The same study also showed drinking a similar number of sugar-sweetened sodas raised the risk of A-fib 10%. Dasgupta said it makes sense to reduce or avoid all sodas and sugary beverages if you can.

"Substituting that with water. I think that we're gonna be on the right track," he said.

Gross said she's not ready to part with her daily diet soda.

"There's a lot of things that are bad for you," she said. "I could go get hit by a car right now. So, I'm gonna enjoy my life when I can."