TAMPA — A sad story out of South Carolina that's still raising a lot of questions.

A 16-year-old collapsed and died.

His family says he stayed away from drugs and alcohol. But it was something legal that led to his death-- caffeine.

Davis Cripe suffered a cardiac event after drinking a Mountain Dew, a latte, and an energy drink in just two hours.

That's more than the safe amount of caffeine for a healthy adult throughout an entire day.

When I first saw this, it really worried me. I have a lot of coffee during the day. Probably five cups or more.

That might be too much. My producers even give me a hard time about it - my wife says you gotta cut back.

So, you have to imagine how shocked I was when I went out to talk to an expert - Dr. Fadi Matar, a cardiologist with USF Health and Tampa General Hospital - about how much caffeine is safe.

MATAR: One, two cups of coffee is good enough. I wouldn't do more than that. You're laughing because you're probably drinking way more than that.

RIVERA: Yeah, I'm drinking way more than that

MATAR: But if you happen to be one of those people predisposed to this, you might be gambling. If anything, I recommend that if you want to drink caffeinated products, limit it to tea and coffee, and don't overdo it.

And Matar says, seriously, stay away from all energy drinks. The FDA says it's probably safe to consume 4 to 5 - 8 ounce cups of coffee a day.

After that you may be in for problems.