The U.S. Food and Drug Administration announced Thursday that it will not review or allow the marketing of cannabidiol, or CBD, products as food items or dietary supplements.
Up until recently, the health agency has not allowed any company to make claims about health benefits from wellness CBD products.
The FDA said after "careful review" it has determined that its current framework for evaluating food and supplements is not set up well for CBD because of safety risks and that substances, including CBD, have to meet specific safety standards to be lawfully marketed as a dietary supplement or a food additive.
"The use of CBD raises various safety concerns, especially with long-term use," FDA Principal Deputy Commissioner Dr. Janet Woodcock said in a statement. "Studies have shown the potential for harm to the liver, interactions with certain medications and possible harm to the male reproductive system."
The statement continued, "CBD exposure is also concerning when it comes to certain vulnerable populations such as children and those who are pregnant."
Woodcock said animals are also at risk of side effects from CBD. People might not know they've been exposed to the ingredient if they consume meat, milk and eggs from animals fed CBD, she said.
"Because it is not apparent how CBD products could meet the safety standard for substances in animal food, we also do not intend to pursue rulemaking allowing the use of CBD in animal food," she said.
The FDA said it plans to "work with Congress" to create new rules for regulating these products, which could include requiring clear labels, preventing contamination, content limits and even a minimum purchase age.
CBD and tetrahydrocannabinol, or THC, both come from the cannabis plant. While THC is the main psychoactive ingredient that gives users the "high," CBD is believed to behind therapeutic effects associated with marijuana such as relief from nausea and pain relief.
The agency also announced it is denying three petitions submitted by citizens asking CBD products to be marketed as dietary supplements.
"Given the available evidence, it is not apparent how CBD products could meet safety standards for dietary supplements or food additives," Woodcock said. "For example, we have not found adequate evidence to determine how much CBD can be consumed, and for how long, before causing harm. Therefore, we do not intend to pursue rulemaking allowing the use of CBD in dietary supplements or conventional foods."
ABC News' Eric Strauss contributed to this report.