The things you use to be friendly to the environment may not be so friendly to your health. In fact, studies show reusable grocery bags could make you sick.
Researchers said the bags have the ability to spread viruses and bacteria.
At a grocery store, Lisa Vroonland packed her groceries in the trunk after making the switch from plastic to reusable.
"I love them! You can fit so much more than a plastic bag; it's so much easier to take into the house. I use them for more than just groceries. They're convenient," said Vroonland.
But could you be sacrificing your health for convenience?
"Unfortunately, if you are not careful, those bags can become contaminated with bacteria and viruses," said Dr. Lawrence Robey with the Madison County Health Department in Alabama.
The Centers for Disease Control has been pushing health departments across the country to spread the word about the dangers lurking in reusable grocery bags.
It became even more apparent after a 2010 outbreak of a norovirus in Oregon where a group of children all got sick after eating cookies that were stored in a reusable bag.
Experts said noroviruses can be a nuisance; they're tough bugs that can live for prolonged periods on objects and surfaces. Norovirus is also blamed for thousands of hospitalizations and deaths every year.
"If a meat package were to leak into a bag, the bacteria may stay there and contaminate future purchases," said Dr. Robey.
Experts advise shoppers to not store bags in the trunk of their cars because it's warm, moist and can sit there for days -- which makes for a perfect breeding ground for bacteria that can multiply.
"It's easy to protect your family. Keep your meats and produce separate, wash them and wash your hands," said Alabama A&M Food Sciences Professor Josh Herring.
"The industry may end up having to label bags with 'safe handling instructions' that say wash after every use for people to understand the seriousness," said Herring.