A study conducted by the Panel on Dietetic Products for the European Food Safety Authority in 2017 concluded that ergothioneine is safe for children above 3 years of age and the general adult population, including pregnant and breastfeeding women
Coordination of circadian clocks in mammals
The BBB gives it a B- and has flagged a pattern-of-complaints alert based on a review in April 2025 covering issues with consumers not receiving their medications and complaints about long phone wait times and unanswered messages
Discuss with your surgeon and prescribing physician
In addition to the well-documented nausea, vomiting, heartburn, bloating, constipation, diarrhea and muscle loss, more serious side effects think pancreatitis, gastrointestinal obstruction, thyroid tumors and vision issues have also been reported.
Taking supplements sporadically won't maintain the steady levels needed for noticeable improvements