Natural supplements used to treat depression should be safe because they’re made with natural ingredients, right?

Not necessarily.

Although the Food and Drug Administration requires strict oversight on prescription medical drugs, natural supplements are subjected to less scrutiny, which has led many to question their effectiveness.

“We really don’t have good data on herbal supplements,” said Diane Birt, distinguished professor of Family and Consumer Sciences. “They are not as extensively tested as drugs.”

Nevertheless, herbal supplements claiming to do everything from managing weight loss to decreasing depression are sold all over the world.

In Ames, the General Nutrition Center at North Grand Mall, 2801 Grand Ave., has been selling natural supplements for over 30 years.

Some of the supplements GNC sells to treat depression include the natural antidepressants S-adenosylmethionine — or SAM-e, St. John’s Wort, fish oils and flaxseed oil.

“St. John’s Wort is used all over Europe for depression,” said Jon Bunger, GNC sales associate.

“German doctors prescribe it to people for that purpose.”

In combination with medication, a recent study found SAM-e to partially relieve depression, but more studies need to be done to confirm its benefits and risks.

“When it gets into these dietary supplements like St. John’s Wort, we have data on the doses that people have taken, but we don’t have data on tests that say, ‘This is a safe intake,'” Birt said. “St. John’s Wort, SAM-e — they’re kind of in that foggy area between a dietary component and a drug. You can make claims, and you don’t have to have scientific data backing them up.”

Herbal supplements may be taken with medicine to help decrease depression, but taking too much could result in an overall negative effect, including flu-like symptoms, said Greg Yeakel, chief of staff at the Thielen Student Health Center pharmacy.

“We do not carry over-the-counter herbal products,” Yeakel said.

“We haven’t perceived a demand. The more that I see in the literature, the more that I’m inclined to say they’re not as safe and as effective as people think they are.”

The most popular medications for depression at the Health Center are Prozac, Zoloft and Lexapro, he said.

“Most people are depressed in their lives. Some are severely depressed so they can’t function normally,” Yeakel said.

“The reason we’re treating more people is we have more effective medicines.”

According to the American College Health Association’s National College Health Assessment, approximately 40 percent of male students and 50 percent of female students were severely depressed in the last school year.

“If you are really sick and you want to get something that will really work, you’re better off going to a physician and getting the medication,” Birt said.

More testing needs to be done on natural supplements to obtain accurate information on benefits and possible side effects, Birt said.

“You don’t know about the purity, and the active ingredient is not well-controlled,” said Diana Wang, pharmacist at Hy-Vee, 640 Lincoln Way.

“Also, they don’t do any clinical trials, so you don’t know about the detailed side effects.”