Mehmet Oz is better known as Dr. Oz, a popular medical talk show host. He has recently been the center of controversy over his support of green bean pills for weight loss. Now, a new study from Canada examines claims made on his show, as well as another medical program.

Two television shows, The Dr. Oz Show and The Doctors, were studied by investigators from the University of British Columbia and the University of Alberta. Researchers researched medical claims made on 40 episodes of each of the pair of series, which aired between January and May, 2013. Investigators rated claims based on how strong they were, and recorded how often they were repeated. The team then randomly chose 160 claims - 80 from each series - and researched the statements made on the shows. They found that just 54.4 percent of the claims made on the television shows were backed by published studies. The remainder of the statements were either not supported, or even contradicted, by peer-reviewed studies, researchers discovered.

"The research supporting any of these recommendations is frequently absent, contradictory or of poor quality," Christina Korownyk from the University of Alberta's Faculty of Medicine and Dentistry, said.

Medical claims made on the Dr. Oz Show were supported by evidence 46 percent of the time, and contradicted in 15 percent of cases. No evidence was found, one way or another, for the efficacy of 39 percent of statements.

The Doctors fared slightly better, with 63 percent of claims on that show supported by scientific articles. Contradictory studies were found in 14 percent of cases, and 24 percent of statements were not examined in investigations.

The Dr. Oz Show provided an average of 12 medical recommendations per episode, 39 percent of which discussed weight loss. The Doctors made an average of 11 such claims each episode, and the most common category were statements advising people to seek out the advice of a physician.

Specific benefits were named for 43 percent of the recommendations on The Dr. Oz Show, the magnitude of which was described in 17 percent of cases. The Doctors labeled benefits from recommendations in 41 out of every 100 cases, along with the degree of relief in 11 percent of the statements. Personal conflicts of interest, which could alter recommendations, accompanied 0.4 percent of the claims made on these shows, according to the study.

A study named as evidence in support of Dr. Oz's claims about the dietary benefits of coffee beans was retracted in November, over questions concerning research methods.

"The public may see these shows as educational. But in many ways we wonder if that's really what they're there for and perhaps they're just there for entertainment," Mike Allan from the Department of Family Medicine at the University of Alberta, stated in a university press release.

Investigation of the medical claims of television shows was published in the journal The BMJ.