Vitamins and Dietary Supplements: AI Market Discovery Index

Benchmark Summary

Thorne led the Vitamins and Dietary Supplements benchmark in September 2026 with valid recommendation coverage of 88.8%, down 2.0 points from 90.8% in August 2026. Pure Encapsulations followed at 74.4%, a gap of 14.4 points. Life Extension recorded the largest coverage increase, rising to 36.4% in September 2026 from 31.0% in August 2026. Ritual recorded the largest coverage decline, falling to 45.8% in September 2026 from 52.4% in August 2026.

Two significant decliners and one significant riser defined a month of mixed movement. Garden of Life fell to 54.3% and Ritual fell to 45.8%, both moves beyond normal month-to-month variation. Life Extension's gain of 5.4 points also exceeded normal variation. Several other brands moved within normal monthly ranges, including Nordic Naturals (down 4.8 points to 34.1%), NOW Foods (up 4.8 points to 53.6%), and Thorne (down 2.0 points).

The benchmark began with 800 prompt-surface observations in each month and produced 753 qualified observations in September 2026 after qualification.

Current Benchmark at a Glance

Qualified surface breadth counts the canonical AI/search surface families with at least one qualified observation: ChatGPT, Copilot, Gemini, Perplexity, AI Overviews, and AI Mode. All six families were represented in both months.

For the strategic interpretation of this benchmark, read CiteWorks Studio's analysis of How AI Search Is Recommending Vitamins and Dietary Supplements

Research Scope and Qualification

The public benchmark is narrower than the raw collection universe by design. In both months the benchmark drew from 800 source prompt-surface observations and retained a qualified subset after filtering for relevance and eligibility.

Brand-level percentages use the qualified observations as the public denominator, not the raw collection. See AI Market Discovery Methodology.

Current Brand Standings

Standings for September 2026, sorted by valid recommendation coverage.

How to Read the Standings

• Presence rate: Share of qualified observations where the brand is mentioned in any way.
• Valid recommendation coverage: Share of qualified observations where the brand appears in a valid recommendation shortlist.
• Top-three rate: Share of qualified observations where the brand appears among the top three recommended options.
• Rank-one rate: Share of qualified observations where the brand is the first recommendation.
• Net sentiment: Positive mentions minus negative mentions as a share of all mentions, on a scale from -1 to 1.

For formulas and denominator rules, see AI Market Discovery Metric Definitions.

Recommendation Coverage Movement

Largest Increase: Life Extension

Life Extension rose to 36.4% in September 2026 from 31.0% in August 2026, an increase of 5.4 percentage points. Presence rate also rose to 39.4% from 34.5%. This is Life Extension's first month of significant upward movement, based on 274 valid recommendation observations in September 2026.

Largest Decline: Ritual

Ritual fell to 45.8% in September 2026 from 52.4% in August 2026, a drop of 6.6 percentage points, with valid recommendations on 345 observations. Presence rate declined to 49.5% from 55.6%. Ritual declined in a single month and is not yet a sustained trend.

Category Leader: Thorne

Thorne remained the coverage leader in September 2026 at 88.8%, down 2.0 points from 90.8% in August 2026, a move within normal month-to-month variation. Top-three rate rose to 70.8% from 62.1%, and rank-one rate rose to 47.7% from 46.0%, both positive movements in placement even as overall coverage eased slightly.

Recommendation Placement Snapshot

Coverage shows how often a brand appears in a recommendation, but not how prominently. Thorne's leading position is reinforced by its placement rates, with top-three and rank-one rates far above its peers.

Pure Encapsulations and Nature Made both show large gains in top-three placement, yet their first-position rates remain well below Thorne's, illustrating how similar coverage levels can still hide different shares of top recommendations.

Buyer-Intent Distribution

All qualified observations in both months fell into the brand recommendation class, which captures shoppers seeking product or brand suggestions.

The current public series measures brand-recommendation discovery only and does not yet contain qualified observations in pricing and value or multi-brand comparison classes.

Historical Measurement Record

New measurements are added to the same benchmark report.

Evidence and Source Layer

The benchmark is built from prompt-level observations that retain the query, AI/search surface, answer, brand outcome, recommendation placement, sentiment, and, where exposed, citations or attributable evidence sources. Source presence is evidence about the information environment: it shows whether an AI answer points to a named source for its recommendation. It is not automatically proof that the source caused the recommendation, and the benchmark does not assert causation from the data alone.

Scope Boundaries

This public benchmark does not measure market share, sales, or attributable conversions. It does not capture every possible AI response, and it does not measure organic-search ranking or social mention volume. Private and sponsored channels are excluded from observation. A movement in any single metric in this benchmark does not by itself establish why that change occurred; it records the change.

About This Benchmark

The LLM Authority Index AI Market Discovery Index is a monthly, neutral industry benchmark tracking how often brands appear in AI-generated recommendations across six canonical AI/search surface families. The index measures presence, valid recommendation coverage, recommendation placement, and sentiment as distinct signals, treating each on its own terms. The public index reports category-level standings only, based on qualified observations with a documented funnel.

• AI Market Discovery Methodology
• AI Market Discovery Metric Definitions
• AI Market Discovery Research Standards
• Modeled AI Authority Value

Get a Company-Level Authority Index

The public industry benchmark shows category-level standings. A company-level Authority Index can go deeper, showing a brand's position against its own category, its movement across individual AI surfaces, and where opportunities appear.

Get my free AI Company Index