Carson first spoke out in favor of Mannatech products over a decade ago when he claimed that the Texas-based company’s “glyconutritional supplements,” which included larch-tree bark and aloe vera extract, helped him overcome prostate cancer.

The company doctor “prescribed a regimen” of supplements, Mr. Carson told its sales associates in a 2004 speech. “Within about three weeks my symptoms went away, and I was really quite amazed,” he said to loud applause, according to a YouTube video of the event. The candidate today is cancer-free after surgery. He told associates of the company, Mannatech Inc., that he initially considered forgoing surgery and treating the cancer with supplements only.

As the Wall Street Journal reported earlier this month, Carson’s relationship with the company deepened over time, including “four paid speeches at Mannatech gatherings, most recently one in 2013 for which he was paid $42,000, according to the company.” The company disputes that Carson was a “paid endorser or spokesperson,” according to the Journal, and claims his financial compensation went to charity.

National Review also highlighted Carson’s connections to Mannatech in January and how Carson’s team went to great lengths to distance themselves from the company. Some of his video appearances have been removed from the Internet, but those that remain appear to show a deeper affiliation than Carson claimed during Wednesday’s debate.

In one video for Mannatech last year that remains online, Carson discusses his experiences with nutritional supplements while seated next to the company’s logo. “The wonderful thing about a company like Mannatech is that they recognize that when God made us, He gave us the right fuel,” Carson explained. “And that fuel was the right kind of healthy food … Basically what the company is doing is trying to find a way to restore natural diet as a medicine or as a mechanism for maintaining health.”

Carson stopped short of making substantive medical claims about Mannatech’s products. “You know, I can’t say that that’s the reason I feel so healthy,” he said. “But I can say it made me feel different and that’s why I continue to use it more than ten years later.” His apparent hesitation is understandable. Seven years before Carson appeared in that video, then-Texas Attorney General Greg Abbott, a Republican who was elected governor of Texas last year, sued Mannatech for running a illegal marketing scheme under the state’s Deceptive Trade Practices Act. Abbott claimed that the Dallas-based company and its sales representatives repeatedly exaggerated the medical efficacy of their products.

“Texans will not tolerate illegal marketing schemes that prey upon the sick and unsuspecting,” Abbott's office said at the time. “Aided by an army of multi-level sellers and their fictitious claims about its products, Mannatech has aggressively marketed supplements to countless unwitting purchasers.” Abbott also emphasized that the company’s claims were “not supported by legitimate scientific studies, nor are its products approved as drugs by the U.S. Food and Drug Administration.”