Brand Competition in US Online Supplements: 2023 Insights

Executive Summary#

Sales of dietary supplements on a leading US marketplace reached US$ 9.6 billion in 2023, yet the ten largest brands hold only a small share of the market between them, so no established incumbent keeps challengers out. We believe brands that target focused subcategories, invest in marketing built for online channels and move into fast-growing formats such as gummies are well placed to win a large position in a fragmented and fast-growing channel.

A Rare Structural Opening: A Fragmented Brand Market#

In most mature e-commerce categories the ten largest brands hold 30–50% of sales, so a handful of established players take much of the market and newcomers find it hard to become visible. The VMS (Vitamins, Minerals & Supplements) market on the marketplace is a clear exception.

Although VMS sales on the marketplace reached US$ 9.6 billion in 2023, with growth of 15.5% YoY, the ten largest brands hold only a small share between them. No single brand holds enough of the market to make it uneconomic for a well-resourced challenger to compete.

We believe this structure comes from the variety of what supplement consumers want. Health goals, preferred dosage forms, lifestyle segments and the signals consumers trust all differ between people buying for immunity, sports performance, healthy ageing and beauty. This variety prevents any one brand from taking the whole market while leaving lasting room for specialists to build strong positions in focused niches.

For brands considering the US online market as an expansion channel, and particularly for Chinese cross-border brands with established manufacturing and formulation capabilities, the fragmentation is a signal they can act on. Targeted clinical positioning and execution built for online marketplaces can win a meaningful share without first displacing an established incumbent.

Category Competition: Where the Volume Is and Where Growth Is#

Within VMS, competition is unevenly spread. Vitamins, minerals and herbal supplements account for more than 60% of VMS sales on the marketplace combined, and this is where established brands compete on price, range of formats and the performance of their subscription repeat-order programmes.

Digestive health is the most important subcategory for competitive strategy. It reached US$ 740 million in 2023, helped by growing consumer awareness of the gut-brain axis, interest in immune resilience after the pandemic and mainstream clinical coverage of probiotics and prebiotics. We believe the subcategory remains underpenetrated relative to the wider VMS market, which leaves room both for established brands extending into digestive health and for challenger brands positioning around science-backed gut formulations. Social media health content has raised awareness of probiotics, and this creates consumer demand that well-positioned product listings can capture organically.

For brand builders, we believe the implication is that the 60%+ share held by vitamins, minerals and herbals represents volume. Digestive health is the subcategory where positions are still being established and where differentiated clinical claims can support a price premium.

Format Competition: Gummies Challenge Capsules#

Competition in the US online supplements market depends on format as well as on the choice of subcategory, since format shapes both the audience a brand can reach and how fast it can grow.

Capsules hold 47% of VMS format share, the largest single segment, a position that rests on long-established efficacy profiles, manufacturing cost advantages and consumer familiarity built over decades. Tablets and powders hold much of the rest, and powders are particularly well established in sports nutrition.

Gummy supplements reached US$ 660 million in sales in 2023, with growth of over 50% YoY, the highest growth rate among all dosage forms. A Harris Poll survey found that 28% of US adults tried vitamin gummies in the past year, and that 53% of those reported daily use. That rate of conversion from trial to a daily habit is unusually high for a new format, and we believe it shows that consumers are adopting gummies as a lasting habit and not only trying them out of curiosity.

We believe gummies are growing because they remove the psychological association between taking a supplement and taking medication, which widens the audience beyond committed health consumers to casual wellness buyers, a larger and faster-growing group. Brands with established positions in capsules face a strategic choice between extending into gummies, and into liquids, which are the next area of fast growth, and accepting a gradual loss of share as format preferences change.

The opening in gummies is still available. Gummy formulation and manufacturing require different capabilities from traditional capsule production, so many established brands have yet to move into the format, and for brands with ready access to contract manufacturing this is an opportunity of timing.

Pricing and Platform Strategy#

The fragmented brand structure on the marketplace shapes pricing in a particular way, because no established incumbent sets the category's price anchors. Price positioning is therefore more open than in concentrated categories. A premium position, however, has to be clearly substantiated, through clinical claims, third-party certifications (NSF, USP, Informed Sport) or trust built through influencers, before consumers who are used to comparing dozens of similar alternatives will pay it.

The subscription repeat-order programme is an important competitive lever. Brands that convert first-time buyers into subscribers build repeat revenue at materially lower customer acquisition costs than competitors that rely on single purchases. High subscription conversion is associated with:

• Strong verified review density (star rating 4.5+ across 1,000+ reviews)
• Consistent formulation and packaging (avoids churn from reformulation)
• Subscription pricing discounts (typically 5–15%)
• Marketplace-fulfilled logistics for reliable delivery

Brands competing in the core vitamins and minerals segments, where price sensitivity is higher, need to compete on unit economics and range of products. Brands entering digestive health or gummies with differentiated clinical claims can aim for higher average selling prices and smaller subscription discounts.

Key Takeaways#

• The ten largest brands hold only a small share of sales, which is unusual for a market of this size, and we believe it shows the market remains open to challenger brands with focused positioning
• Vitamins, minerals and herbal supplements hold 60%+ of category sales combined, where volume and competition are both high
• Digestive health reached US$ 740 million in 2023 and remains underpenetrated, which we believe makes it the clearest growth opportunity among the subcategories
• Gummy supplements grew over 50% YoY to US$ 660 million, and 53% of those who tried them use them daily, so we believe the change of format will last
• Platform strategy, including subscription programmes, the pace of reviews and marketplace fulfilment, is as important as formulation in determining a brand's competitive position online

About the Data#

This article draws on Moojing's January 2024 brief on the US dietary supplements category on one leading US marketplace. Quantitative data cover the full calendar year 2023 and are from MoAnalysis, Moojing's cross-border e-commerce analytics platform. Consumer survey data on gummy adoption and frequency of use are from Harris Poll.