Taurine levels are lower in long COVID and ME/CFS, but taking supplements doesn’t seem to clear up brain fog — and might not help everyone.

Research does show that people with long COVID and ME/CFS tend to have lower taurine in their blood than healthy individuals, which is a real and interesting finding. But when it comes to taking taurine supplements, the picture gets murky: one study gave people up to 3000 mg a day and found no improvement in brain fog, even though other symptoms improved. That directly challenges the idea that boosting taurine will help cognition. Meanwhile, some people anecdotally say they feel clearer, but there’s no solid study backing that up yet. And yes, there’s some evidence that people with ME/CFS might have trouble processing sulfur-containing compounds like taurine, which could explain why a few feel worse instead of better.