GRAND RAPIDS, Mich. (WOOD) — It’s something that many of us feel we need to get the day started off right: caffeine.

Doctors say the stimulant usually doesn’t lead to health problems, but it’s important to be mindful of its side effects.

“The (U.S. Department of Agriculture), the (Food and Drug Administration), both of those organizations are going to recommend that 400 mg is typically what’s deemed safe for most adults,” said Shanthi Appelo, a registered dietitian with Blue Cross Blue Shield of Michigan.

For reference, Appelo said there’s about 100 mg of caffeine in an 8 oz cup of coffee, a cup of tea has 50 mg and a 12 oz cola has 50 mg. Herbal tea doesn’t have caffeine.

Appelo said in younger people, extreme caffeine like powder caffeine can be dangerous and has been leading to emergency room visits for heart issues.

Appelo said the half-life of caffeine is four to six hours and some people are more sensitive to it than others.

“After you consume caffeine, half of that caffeine is still going to be present in your system after that time,” Appelo said.

People 65 and older process caffeine at a slower pace.

“If you’re a tea drinker, switching to herbal teas can be a really good idea. It’s also a good idea just to be mindful of how that caffeine racks up throughout the day,” said Appelo.

For the full conversation with Shanthi Appelo, watch the video in the player above.