CBD products can still contain THC—and for marathon runners and other tested athletes, that detail really matters.
Why CBD Products May Contain THC
Experts say it starts with the plant and the law. In the United States, “hemp” is defined as cannabis containing no more than 0.3% delta-9 THC by dry weight. That means many legal hemp-derived CBD oils, gummies, and drinks are allowed to include some THC, as long as they stay under that limit.
In practice, several product types naturally carry trace THC:
- Full-spectrum CBD: intentionally keeps a range of cannabinoids (including small amounts of THC) and terpenes to preserve the plant’s “entourage effect.”
- Broad-spectrum CBD: is supposed to remove THC, but processing is not always perfect.
- CBD isolate products: are marketed as THC-free, yet manufacturing or labeling errors can still introduce low levels of THC.
Regulators have repeatedly warned that many CBD products are misbranded or inaccurately labeled, with variable cannabinoid content and undeclared THC. For everyday consumers, that might only mean an unexpected mild psychoactive effect. For athletes, it can be a career-defining problem.
What This Means for Marathon Runners and Tested Athletes
Under World Anti-Doping Agency (WADA) rules, only cannabidiol (CBD) is exempt from the prohibition on cannabinoids. All other natural and synthetic cannabinoids—including THC—are banned in-competition.
USADA and other anti-doping bodies routinely remind athletes that CBD products may still contain THC and that athletes are “strictly liable” for anything found in their system, even if the THC came from a mislabeled CBD product.
Key details for marathoners:
- THC has a urine threshold of 150 ng/mL in WADA-accredited labs. Levels above that during competition trigger a positive test.
- Regular use of full-spectrum CBD—or high doses of “THC-free” products that actually contain THC—may push an athlete over that threshold, especially close to race day.
- Because CBD products are often taken daily for recovery, sleep, or pain, even “trace” THC can accumulate over time.
For a recreational runner, this might only be an unpleasant surprise. For an elite marathoner, it could mean disqualification, loss of prize money, or suspension.
Practical Takeaways for Athletes
A CBD product expert would typically advise competitive runners to:
- Favor CBD isolate from brands that provide recent, third-party certificates of analysis (COAs) showing “non-detectable” THC.
- Avoid full-spectrum products during the weeks leading up to competition.
- Work with team doctors or sports dietitians who understand WADA and national anti-doping rules.
- Keep in mind that regulations and enforcement continue to evolve, and policy shifts around hemp-derived THC products may further change what’s on shelves in the coming years.
CBD itself is not banned, but the way it’s formulated can make or break an athlete’s compliance. For marathon runners chasing both PRs and podiums, understanding the THC question inside their CBD bottle is now part of race preparation.