How do regulators (FDA, Health Canada, EU) currently label or restrict green tea extract in dietary supplements?
Executive summary
Health Canada now permits standardized green tea extract (GTE; EGCG/catechins) as a supplemental ingredient but requires compositional limits and explicit cautionary labelling to reduce liver‑injury risk, including a recommended maximum daily intake tied to background tea consumption [1] [2]. The European Union has moved to legally cap EGCG in foods and supplements—labels must warn consumers and keep single‑day EGCG below 800 mg—while U.S. federal regulators rely on existing dietary‑supplement law, GRAS notices and guidance rather than a single EU‑style cap, with FDA actions historically focused on adverse‑event review and trial safeguards [3] [4] [5] [6] [7].
1. How Health Canada treats green tea extract: permitted with limits and mandatory cautionary labels
Health Canada completed a premarket safety assessment and added green tea extract (characterised by EGCG and total catechins) to its List of Permitted Supplemental Ingredients with conditions of use that include compositional requirements and a derived recommended maximum daily intake (RMDI) informed by background dietary exposure—roughly one cup of green tea ≈100 mg EGCG—so that supplemented foods do not push consumers far beyond normal intake [1] [2]. Health Canada explicitly requires a cautionary statement—“Do not [eat/drink] on the same day as any other supplemented foods or supplements with green tea extract (EGCG/catechins)”—to prevent cumulative overconsumption and to mitigate the documented concern about liver injury noted in the literature [1]. The Department also distinguishes flavouring use (not regulated as a supplemental ingredient if it contributes no more EGCG than one cup of brewed green tea) from intended supplemental uses that trigger the labelling and compositional rules [1].
2. The EU’s regulatory intervention: a numeric cap, warnings for vulnerable groups, and novel‑food carve‑outs
Following EFSA’s 2018 scientific opinion linking high supplemental EGCG doses with an increased likelihood of liver damage, the EU adopted binding limits requiring that a daily serving of GTE in foods and supplements contain less than 800 mg EGCG and that labels state the 800 mg total daily maximum must not be exceeded; labels must also warn children under 18, pregnant or lactating people, and advise against consumption on an empty stomach or with other green‑tea products the same day [3] [4] [7]. The EU regulation also preserves distinct treatment for highly purified EGCG preparations authorised as novel foods (≥90% EGCG), which remain subject to novel‑food conditions and may carry separate constraints [4]. This approach hard‑caps risk exposure at a level EFSA judged prudent given heterogeneous catechin compositions and case reports of liver adverse events [3] [7].
3. The U.S. posture: no uniform numerical limit, case‑by‑case reviews, GRAS processes and labelling frameworks
Unlike the EU, the U.S. does not presently impose a single federal EGCG limit for supplements; instead, oversight falls to the Dietary Supplement Health and Education Act framework, FDA guidance documents and product‑specific submissions such as GRAS notices and adverse‑event monitoring [6] [5]. FDA has historically paused or restricted certain EGCG clinical trials pending toxicity reviews, and reviewers have required administration with food in past trials—signalling concern about fasting‑state toxicity—while independent bodies like U.S. Pharmacopeia recommended cautionary labelling in monographs rather than wholesale bans [7] [8]. Industry has pursued GRAS determinations for modified catechin ingredients for use as antioxidants in foods, a route that places safety assessment in the dossier and regulatory response letters rather than prescriptive numeric caps [5] [9].
4. The evidence gulf, competing agendas and what the rules conceal
Regulators’ actions reflect a tension between facilitating market access for botanical ingredients and protecting public health from rare but serious liver‑injury signals; Health Canada and the EU opted for explicit labelling and quantitative constraints, while the U.S. system leans on post‑market surveillance, premarket notices and voluntary monographs [1] [3] [6] [8]. Industry trade and novel‑food pathways can preserve product classes (e.g., purified EGCG novel‑food authorisations), creating a regulatory patchwork where safety depends on composition, declared use and manufacturer compliance—a dynamic that advantages firms that can fund submissions and testing [4] [5]. Scientific panels continue to debate tolerable upper intake levels (examples proposed: 300 mg/day or 4.6 mg/kg/day from differing analyses), underscoring remaining uncertainty and the rationale behind divergent national approaches [7].
5. Bottom line for consumers and policymakers
Where regulators have acted—Canada and the EU—they require explicit labelling and compositional limits to prevent cumulative EGCG exposure linked to liver risk; in the U.S. no single federal EGCG cap exists, but FDA oversight, GRAS reviews and adverse‑event reporting shape what reaches the market, and independent bodies urge cautionary labelling [1] [3] [6] [8]. Public‑health tradeoffs, industry interests and evolving clinical evidence explain the differences, and gaps in long‑term human data mean regulators will likely continue refining limits and label language as new safety signals or compositional analyses emerge [7].