Modern-day scientists have confirmed what European folk healers have known for thousands of years: Roseroot — an herb — contains compounds that regulate “feel-good” chemicals in the brain that depression and may even boost longevity.

In a new study, published in the journal Phytomedicine, University of Pennsylvania researchers compared the effects of roseroot extract with sertraline — a commonly prescribed antidepressant therapy — in 57 people with mild to moderate depression, Medical News Today reports.

The results of the head-to-head comparison showed both treatments were effective in improving symptoms, with those receiving sertraline only slightly likely to report improvements after 12 weeks, compared to those receiving roseroot extract.

But far more patients receiving sertraline (63 percent) reported side effects than those receiving roseroot (30 percent), suggesting the herb may have a more favorable risk-to-benefit ratio than sertraline for treating mild to moderate depression.

"These results are a bit preliminary but suggest that herbal therapy may have the potential to help patients with depression who cannot tolerate conventional antidepressants due to side effects," said lead researcher Jun J. Mao, M.D., associate professor of family medicine, community health and epidemiology at the Perelman School of Medicine at UPenn.

Roseroot (Rhodiola rosea) has been used in traditional folk medicine for nearly 3,000 years to boost energy, increase longevity, and combat altitude sickness and depression.

Past studies have suggested that roseroot may regulate “feel-good” chemicals in the brain, such as dopamine and serotonin. Other research also suggests the herb affects beta-endorphin levels in the body.

Depression strikes more than 19 million Americans each year and is linked to a high risk of suicide and a variety of physical illnesses. Up to 70 percent of patients don’t benefit from conventional antidepressants, which often have significant side effects that prevent patients from completing a course of treatment.

"Furthermore, many individuals with more mild depressive symptoms weigh concerns over side effects alongside the limited benefits and costs of conventional antidepressant therapy," said the researchers. "Thus, it is not surprising that depressive symptoms are among the most common reasons cited by consumers to choose alternative therapy.

"[Roseroot] may be better tolerated than sertraline, which suggests its potential as a treatment alternative for patients who are intolerant to the adverse effects of conventional antidepressants.”