Traditional Chinese medicine has received a vote of confidence from the World Health Organization. China’s World Federation of Chinese Medicine Societies, a Beijing organization that promotes traditional Chinese medicine, has established official relations with the WHO, and will now be able to attend WHO meetings, and “have a say in global decision-making on major health issues,” according to the group.

“The WHO recognizes the value and role traditional medicine can play in national health systems, especially in primary care,” WHO’s representative in China, Bernhard Schwartlander said, according to Chinese media. (The WHO was not immediately available for comment.)

Despite its over 3,000-year history, the jury is still out on the effectiveness of traditional Chinese medicine, or TCM, which ranges from acupuncture to herbal concoctions, Tai Qi, and dietary advice. The United States’ National Institute for Health says that “there is not enough rigorous scientific evidence to know whether TCM methods work for the conditions for which they are used.”

The Chinese government’s support for promoting TCM, popular in much of China and East Asia, dates back to the 1950s. But even Mao Zedong once admitted, “Even though I believe we should promote Chinese medicine… I personally do not believe in it. I don’t take Chinese medicine.”

Over the past few years, as TCM has become more popular, scientists have collected evidence that at least some chemical components of herbs and materials used in TCM are effective. Last month, a study found that the chemical tetrandrine, found in the stephania root, known in Chinese as hanfangji andused as an anti-inflammatory remedy,can help ward off the Ebola virus. Last year, a study found that TCM helped reduce angina, or chest pain in test subjects.

And in 2008, a group of researchers found that 1,235 chemical components  in TCMs were either included or structurally similar to those in the Comprehensive Medicinal Chemistry database for approved chemical agents. “All of these findings suggest that TCM, at least in part, has a scientific basis,” those researchers wrote in 2008.

But doubts about TCM, and how it is regulated, remain. Producers of TCMs have been known to add toxins, undisclosed drugs, and heavy metals in some cases, to increase the appearance of effectiveness.

Skepticism is compounded by the fact that the popularity of TCM is believed to drive much of the trade in endangered animals parts. A study by researchers at Murdoch University in Australia in 2012 found that 78% of samples tested included animal DNA that was not listed—as well as unlisted ingredients like ephedra, a poisonous herb banned in the US, and aristolochic acid, a carcinogen.