Bubba Watson nervously adjusted his shirt and paced aimlessly between shots. He was playing alongside J.B. Holmes in the Zurich Classic, a low-key team event that’s considered by many a relaxing change of pace from the week-to-week grind on the PGA Tour. But Watson was his predictably fidgety self.

The 40-year-old admits to losing focus and being easily distracted during rounds and once told reporters he’d diagnosed himself with Attention-Deficit Disorder. Less than a week after the Zurich, Watson announced he’d signed a multi-year partnership with cbdMD, which produces products containing cannabidiol (CBD).

The U.S. Food and Drug Administration doesn’t allow companies like cbdMD to market CBD products – which range from hemp-oil extracts to gummies – as treatments or cures for diseases like epilepsy, diabetes and Alzheimer’s, or psychiatric issues like anxiety or depression. But as a growing list of Tour players who endorse the use of CBD products suggests, the benefits, either real or perceived, are difficult to ignore.

“Each person is going to have a different experience with CBD,” said Dr. Craig Davies, a longtime trainer on Tour whose clients include Hunter Mahan, Justin Rose and Matt Kuchar. “A lot of times people experience anti-anxiety; anti-pain is a big one because of the anti-inflammatory effects. Because of the way it interacts with your system a lot of people sleep better and for longer periods of time. If you’re sleeping longer your body has a better chance to recover.”

It’s no surprise that CBD products have started to be billed as a miracle supplement in many circles. In April, Scott Piercy announced an endorsement deal with Real Brands, an e-commerce company that offers a variety of CBD products, and PGA Tour Champions player Scott McCarron has a similar agreement with Functional Remedies, a hemp-oil company that also partnered with the Rapiscan Systems Classic on the over-50 circuit.

Although the Tour has no estimates on CBD use among Tour players, anecdotally the product’s popularity has increased dramatically over the last 12 months.

“It’s increasing on a weekly or monthly basis,” Davies said. “Last year it would have been relatively difficult to find someone who was taking it. By next year it will be difficult to find someone who is not taking it.”

Big things happening up here in NY! @cbdmd_usa pic.twitter.com/Xrs4DwXAiq

— bubba watson (@bubbawatson) May 1, 2019

The World Anti-Doping Agency (WADA) opened the door to CBD use in sports in January 2018 when the agency removed the product from its list of prohibited substances. While cannabis remains on the banned list – which is the same list used by the Tour’s anti-doping program – as long as a CBD product contains less than 0.3 percent of Tetrahydrocannabinol (THC) it would not be considered a controlled substance at the federal level and would not lead to a testing violation.

As is the case with most elements of anti-doping, however, that threshold is not as clear cut as it may seem.

In the April issue of the Green Sheet that’s sent to Tour players, the circuit warned “CBD products (like all supplements) pose a risk to athletes because they have limited government regulation and may contain THC.”

The warning went on to explain that the FDA and Major League Baseball conducted tests on various CBD products only to find significant levels of THC. In the Draconian world of anti-doping, taking a mislabeled supplement is not a defense for a testing violation.

“There is a level of concern for me in respect to any supplement,” said Andy Levinson, the Tour’s senior vice president of tournament administration. “The industry is so poorly regulated there is no assurance. For us, when a player inquires about a supplement we tell them there is a risk.”

The rule in anti-doping circles is to always tread carefully, but the Tour’s decision to lean into the discussion about CBD use is more than simply an over-abundance of caution. For Davies, who has become something of a CBD expert on Tour, his conversations with players always begin and end with a clear disclaimer.

“The No. 1 thing, if you are going to use a product you have to know where they are going to be sourcing it from,” Davies said. “A lot of products get their hemp from China and there’s no way of telling the quality of the product. There are no lab results so you really don’t know what you’re taking and that’s a problem, not only from the fact you can test positive if it has too high of levels of THC, but more importantly you don’t know what you’re getting.”

A 2017 study published by the American Medical Association found that 69 percent of the CBD products examined contained different levels of CBD than what was identified on the label and that THC was detected in 21 percent of those products.

“The supplement market was like that for a long time. You could go in a GNC and buy a weight-gaining product and they said 50 percent of those products would test positive under the MLB anti-doping regulations,” said Victor Trasoff-Jilg, who worked on Tour for nearly a decade as a trainer before joining WAAYB Organics, a Colorado-based CBD manufacturer. “It’s basically what protein powder was back in the early 2000s.”

The anti-doping concerns stem from how difficult it is to remove all of the THC from CBD products. This THC-free version is called isolate which Davies said lacks the desired effect.

“If you take the full plant extract you have the terpenes, CBD, as well as a very low dose, usually 0.1 or 0.2 percent, of THC,” Davies said. “They’ve actually shown that the THC at that low of a dose is not psychoactive and it increases the effect of the other components of the plant. It’s actually a better-quality plant for anti-anxiety, promoting sleep, anti-pain and anti-inflammatory.”

Although there are a variety of ways to use CBD the most effective and popular method is sublingually, using an oil under the tongue, and Davies said he has clients with knee and back arthritis who have had “very good responses” to CBD use. He also said that the supplement has shown to be effective for those with anxiety issues, which could prove particularly concerning to the Tour.

The Tour’s current list of prohibited substances includes beta blockers, which are prescribed for those with heart conditions. It’s also considered an anti-anxiety agent which could prove particularly beneficial for a golfer on Sunday afternoon at a Tour event when the pressure is magnified.

So why would CBD be any different?

“To be clear, those [anti-anxiety] claims are used by the manufacturers. They are not supported by any substantive research,” Levinson said. “There are no facts [about] what the manufacturers claim the benefits are. The reality is WADA scientists looked into it and did not find the substance to be performance enhancing.”

For a player like Watson, who said CBD allows him to sleep better and helps reduce inflammation, the purported anti-anxiety benefits may not be scientifically proven, or even individually beneficial. But as CBD use continues to gain acceptance on Tour the conversation about the supplement’s perceived benefits is sure to continue.