Across 124 first-hand reports, people mentioned a side effect 6 times (about 5 per 100 reports). The most common: stomach issues, anxiety, irritability. User reports show what people notice — they can't tell you whether Sulforaphane is safe for you.
“sulforaphane, which has helped me a lot, but may not help everyone with anxiety”
Conclusion: Some medications could improve core symptoms, although this could be likely secondary to the improvement of associated symptoms. Evidence on their efficacy and safety is preliminary; therefore, routine prescription of medications for the core symptoms cannot be recommended. Trial registration PROSPERO-ID CRD42019125317.
Conclusion: The vast majority of the results cast doubt on previous assumptions claiming that brassica plants have antithyroid effects in humans. Instead, they indicate that including brassica vegetables in the daily diet, particularly when accompanied by adequate iodine intake, poses no adverse effects on thyroid function.