The short answer. There isn't much data on Black Cumin yet — 6 mentions, 0 with a clear outcome — so treat these numbers as anecdotal. It is well studied — 5 meta-analyses on PubMed.
Out of 6 mentions; the other 100% didn't say how it went and aren't counted.
Of the people who reported each effect, the share who said it got better.
Systematic reviews and meta-analyses from PubMed, with their published conclusions.
3+ meta-analyses or systematic reviews and 10+ randomized controlled trials in humans. The grade measures how much human research exists — read the conclusions below for what it found.
Conclusion: Only ginger and black cumin reported a significant improvement in glycated hemoglobin, and only cinnamon and ginger showed a significant decrease in insulin.
PubMed 38542668 ↗Conclusion: Conclusion: There is moderate to high level of evidence from randomized controlled trials that the Ayurvedic herbs guggulu, garlic, and black cumin are moderately effective for reducing hypercholesterolemia. In addition, minimal evidence was found for any side effects associated with these herbs, positioning them as safe adjuvants to conventional treatments.
PubMed 34071454 ↗Conclusion: In addition, the overall pooled estimate of the level of serum insulin was significant with SMD of 1.681 (95%CI: 0.858, 2.503; p = 0.000). Therefore, the meta-analysis showed that TQ has a significant antidiabetic effect through its action on the SG, serum insulin level, and BW of the animals.
PubMed 31882078 ↗Conclusion: Nigella sativa was shown to significantly improve laboratory parameters of hyperglycemia and diabetes control after treatment with a significant fall in fasting blood glucose, blood glucose level 2 h postprandial, glycated hemoglobin, and insulin resistance, and a rise in serum insulin. In conclusion, these findings suggested that Nigella sativa could be used as an adjuvant for oral antidiabetic drugs in diabetes control.
PubMed 31817324 ↗As stated by users — not a recommendation. Follow the label or your doctor.
How often each side effect came up across all reports.
First-hand experiences, quoted verbatim. We show one positive and one negative where both exist.
User data from public discussions; research from PubMed. Information only, not medical advice — talk to a doctor before starting, stopping or combining anything. Data updated October 3, 2026. How we rate