A La Roche-Posay serum built around the Melasyl ingredient and niacinamide (vitamin B3), designed to target dark spots and uneven skin tone.
Guru Score
The Guru Score: every expert's verdict on a product, in one simple number.
Under the score you'll see how many experts weighed in, or "Early verdict" while only a few have. Paid takes count for half in the score.
Guru Certified means at least 6 experts, a score of 85% or more, and almost no Nays.
How we score →Mixed
Early verdict · Few reviews so farWhat the gurus are saying
Melasyl looks great in the research, yet the takes split on whether it shows up on real skin. Some saw no results at all, even with samples and full sizes, and say skip it for now. Others say it can work if you tolerate it, perhaps twice a day, and since the brand's sunscreen has it too, sunscreen by day with serum at night is reasonable.
What they liked
What they flagged
No single complaint stood out. The mixed and skipped takes below carry the reservations.
Best for
Type
Key actives
Formula notes
The concerns the experts tie this product to, in their own words. Paid and founder takes don't count.
Every take we've logged from this product's reviews across YouTube. Click any row to watch the moment they said it.
Independent of what the gurus think, this is what the published research supports about the main active ingredients here.
A La Roche-Posay serum built around the Melasyl ingredient and niacinamide (vitamin B3), designed to target dark spots and uneven skin tone.
The gurus mostly approve it, but with enough reservations to keep it in the middle at a Guru Score of 61%.
La Roche-Posay Melasyl B3 Serum holds a Guru Score of 61%. That is our read on how warmly the experts talk about it, based on the verdicts of 2 expert reviewers we have collected.
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