La Roche-Posay Mela B3 Niacinamide Serum: Formula, Ratings and Price Analysis

What the listing publishes about La Roche-Posay Mela B3 Niacinamide Serum: positioning, specification sheet, headline claims and the photography used on the detail page. Everything below is a snapshot of the Amazon US detail page taken on 2026-10-31, with prices read against a US delivery address.

Specification sheet

What the brand claims

Product images

Three listing frames per row, exactly as published on the Amazon detail page.

Real product photos

The listing rendered no buyer-uploaded photo tiles at capture time; the frames below are additional Amazon listing photography rather than customer uploads.

The score and its distribution, then the themes buyers actually write about. Review content is aggregated only: no reviewer name, handle, avatar or profile link is reproduced anywhere in this analysis.

Rating distribution

What buyers talk about

Customers say

Reading the signal

The distribution is top-heavy: 73% of ratings sit at five stars and a further 10% at four, which is the shape of a product that satisfies most first-time buyers. The tail is not noise, though — 8% at one star is a visible minority, and the aspect table shows where the disagreement concentrates: value for money is the weakest theme at 31% positive across 235 mentions, while non-greasy reaches 96%. The friction is not the experience of using the product, it is what the experience costs — the price is the single theme buyers push back on.

Confidence: high for the aggregate score and histogram (published directly); medium for the aspect split, which is a model-generated summary rather than a vote count and does not sum to the rating total.

Two independent ingredient databases were merged into a single table: COSDNA supplies acne risk, irritant and safety grades, Skinsort supplies position order, function and comedogenic / irritancy ratings. Where both index the same ingredient the rows are fused; where only one does, the gap is shown rather than filled.

Matching outcome: 32 ingredients agreed exactly across both databases, 0 appear only in COSDNA and 0 only in Skinsort. Skinsort's own community read on this formula is 2.8 from 16 reviews at a $$$$ price band — a small sample, useful as a second opinion only.

Ingredient level classification

Every ingredient carrying a COSDNA safety grade is bucketed by it. The scale is inverted: 1 is the safest reading and higher numbers mean more caution is warranted, so the two left-hand bands are the clean ones. Not rated means the database holds no entry, not that the ingredient is harmless.

Function profile

The profile is a classic emulsion serum: a water and solvent base, a small silicone and emollient load for slip, one humectant cluster and a short preservative tail. The actives concentrate in three names — niacinamide, the patented Melasyl molecule (2-mercaptonicotinoyl glycine) and a retinyl ester — which matches the marketing claim rather than contradicting it.

Flagged ingredients

Rows below appear because at least one published grade reaches 3 or higher on acne, irritancy, safety or comedogenicity. A 3-plus safety grade on a fragrance or a preservative is a class-level flag, not a prediction about this formula.

What's inside: claim matrix

Free-from claims are printed exactly as the aggregator grades them. A "NO" is a failing claim, not a neutral reading — the fragrance line in particular is worth reading twice.

Flagged concerns

Key ingredient groups

Benefits the formula supports

Bar length is the number of ingredients the aggregator credits for each benefit; a one-ingredient claim is a weak signal, not a promise.

Complete ingredient table

32 rows in published order. Columns 4 to 6 come from COSDNA, columns 7 and 8 from Skinsort. Blank cells are rendered as not rated.

Reading notes. Acne risk and irritancy are read low-is-safer. Safety is an inverse grade where 1 is the least concerning. Where a source prints a range such as 1-9 the upper bound is used for banding, so an ingredient is never quietly upgraded. Two rows printed only two of the three grades (Caprylic/Capric Triglyceride and Octyldodecanol); the printed values were assigned to acne risk and irritant in that order and safety was left unrated, so treat those two cells as alignment-inferred rather than published.

The current ask, the surrounding history, and how the price behaves against its own floor, its average and the list price. All figures are USD as rendered for a US delivery address; nothing here is converted from another currency or estimated.

Price history by channel

The tracker's summary block is all-time by construction: changing the chart window re-scales the line but never re-computes these five values, so no period-specific low or high can be read from it. The last observation in this record is dated 2026-10-30, 1 days before the collection date, and the tracker reports its last scan as “8 hours ago”. Treat the live figure as up to 1 days old rather than as a today quote.

Channel comparison

Four bars per price type — the historic floor, the average, the live price and the historic ceiling. Where a channel has no data the bars collapse to zero and the table above reads as a dash.

Price trend from dated observations

The tracker publishes only the dated extremes and the last observation, not a full observation series, so the line below connects the actual dated points rather than inventing intermediate values. Read it as the shape of the record, not as a daily series.

Derived position

What the price record says

The live price of $44.99 sits +1.7% against its own all-time average of $44.24, and +56.9% above the historic floor of $28.67 first touched on 2026-08-20. That distance is the real promotional room: a campaign that does not approach the floor is cosmetic discounting, not a structural price move.

Third-party new averages $41.61 against Amazon's $44.24, a gap of $-2.63. The premium is the marketplace's own read on availability — while the buy box is stable the gap compresses, so a widening spread is an early warning that supply is thinning.

Confidence: high for the transcribed prices and dates, medium for the interpretive paragraphs, which reason from five values per channel rather than from an observation log.

Methodology, scope and confidence