21 botanicals · last reviewed 2026-09-30

Tea & infusion reference

Caffeine per cup, what each botanical is actually used for, how strong the evidence is, what to test for, and the cautions that belong on the pack. Written for both sides of the counter: brands designing a blend and drinkers reading one.

Green tea

True tea (Camellia sinensis)

Camellia sinensis · Approx. 25–50 mg per 200 ml cup

Positioning: Antioxidant and metabolism positioning; the base of most 'slimming' and 'detox' blends.
Evidence: Catechin intake is studied widely. Effects on weight are small and inconsistent in human trials, and most marketing overstates them.
What to check: Garden and estate, harvest season, leaf grade, pesticide residue testing against the destination market's MRLs, and lead content.
Cautions: Contains caffeine. Concentrated green tea extracts are linked to liver injury and carry warnings in several markets — the tea itself is a different exposure from a high-dose EGCG capsule.
Market status: A food in most markets. Health claims about weight loss are restricted or prohibited in the EU, UK and US.

Black tea

True tea (Camellia sinensis)

Camellia sinensis · Approx. 30–60 mg per 200 ml cup

Positioning: Everyday morning tea and the base of spiced blends.
Evidence: The most consumed tea category globally; cardiovascular associations appear in population studies rather than trials.
What to check: Origin and grade (orthodox versus CTC), pesticide MRL testing, and whether the leaf is blended from multiple origins — declare it if so.
Cautions: Caffeine. Tannins reduce iron absorption from plant foods when drunk with meals.
Market status: Food. No claims required or permitted for a standard product.

Oolong

True tea (Camellia sinensis)

Camellia sinensis · Approx. 20–45 mg per 200 ml cup

Positioning: Between green and black, marketed for metabolism and weight management.
Evidence: Some small human studies on oolong and energy expenditure exist; the effect size is modest.
What to check: Oxidation level, roast level, and whether the leaf is from a single origin or blended — the price difference is large and buyers are often misled.
Cautions: Caffeine. Strong roast flavours divide consumers; order sensory samples from the actual production lot.
Market status: Food in most markets.

Matcha

True tea (Camellia sinensis)

Camellia sinensis · Approx. 50–70 mg per 200 ml cup

Positioning: Ceremonial positioning, high perceived quality, used in lattes, powders and gummies.
Evidence: Same catechin literature as green tea, with the difference that the whole leaf is consumed rather than infused.
What to check: Grade (ceremonial, premium, culinary), colour and freshness, origin prefecture, and pesticide and heavy-metal testing — tea plants accumulate soil metals.
Cautions: Higher caffeine than an equivalent cup of green tea. Concentrated extract cautions apply as above.
Market status: Food. 'Ceremonial' is a trade grading term, not a legal standard — define it in your specification.

White tea and pu-erh

True tea (Camellia sinensis)

Camellia sinensis · Approx. 15–45 mg per 200 ml cup

Positioning: Craft and premium positioning; pu-erh is fermented or aged, white tea is minimally processed.
Evidence: Both are usually sold on craft and taste rather than on a health endpoint.
What to check: For pu-erh: storage conditions and history, mould testing, and origin authenticity, which is frequently falsified.
Cautions: Poorly stored pu-erh is a mould and mycotoxin concern — insist on storage documentation and microbial testing.
Market status: Food. Aged and fermented products attract specific hygiene scrutiny in some markets.

Chamomile

Herbal infusions

Matricaria chamomilla · None

Positioning: Calm and sleep blends; the most familiar caffeine-free herbal base.
Evidence: Small trials in sleep quality and anxiety; evidence is modest but the ingredient is well tolerated by most people.
What to check: Pesticide residues, flower-to-stem ratio, essential-oil content as a quality marker, and allergen declaration.
Cautions: Allergy risk in people sensitive to Asteraceae plants (ragweed, daisy, chrysanthemum).
Market status: Traditional food in the EU and UK; a dietary ingredient in the US.

Peppermint and spearmint

Herbal infusions

Mentha × piperita, Mentha spicata · None

Positioning: Digestive comfort and fresh flavour; also the mint in 'slimming' blends.
Evidence: Peppermint oil has reasonable evidence in irritable bowel symptoms; mint tea itself is largely consumed for taste and comfort.
What to check: Pesticide residues and essential-oil content, which drops quickly with poor storage.
Cautions: Can worsen reflux in some people. Peppermint is not recommended for infants. Spearmint has been studied in women with hormonal acne but is not a treatment.
Market status: Food.

Rooibos and honeybush

Herbal infusions

Aspalathus linearis, Cyclopia spp. · None

Positioning: Caffeine-free daily blend base, marketed for antioxidants and for being minerally rather than bitter.
Evidence: Antioxidant content is documented; human clinical evidence for specific outcomes is limited.
What to check: Origin certification (rooibos is a protected geographical indication), colour and grade, and pesticide residues.
Cautions: Generally well tolerated. Avoid overstating antioxidant claims, which are restricted in several markets.
Market status: Food. Rooibos has a protected designation in the EU — using the name on non-South African material is a mislabelling risk.

Hibiscus

Fruit, floral & spice

Hibiscus sabdariffa · None

Positioning: Tart, deep red base used in 'detox', beauty and blood-pressure-adjacent blends.
Evidence: Blood-pressure effects appear in small randomised trials; the evidence is not strong enough for a general claim.
What to check: Pesticide residues, colour intensity and adulteration with cheaper flowers, and moisture content for shelf life.
Cautions: May add to the effect of blood-pressure medication. Can lower blood pressure in sensitive people.
Market status: Food. Blood-pressure claims are medicinal claims and are not permitted on a food in the EU or UK.

Lemon balm

Herbal infusions

Melissa officinalis · None

Positioning: Calm, sleep and 'mood' blends.
Evidence: Small studies in stress and sleep; evidence is modest.
What to check: Essential-oil content (citral, citronellal) as a freshness marker, and pesticide residues.
Cautions: May interact with thyroid medication. Sedative-type effects are possible at high intakes.
Market status: Food.

Valerian and passionflower

Herbal infusions

Valeriana officinalis, Passiflora incarnata · None

Positioning: Night-time and sleep blends; often combined with chamomile and lemon balm.
Evidence: Evidence in insomnia is mixed, with small trials and inconsistent results across preparations.
What to check: Species and part used (root versus rhizome), extract ratio, and the absence of adulteration — both are commonly substituted.
Cautions: Drowsiness, and additive effects with sedatives, alcohol and some antidepressants. Not for children or in pregnancy without professional advice.
Market status: In several EU member states these herbs are treated as medicines, so a product containing them may not be a food supplement at all. Check the classification before formulating.

Licorice root

Adaptogens & roots

Glycyrrhiza glabra · None

Positioning: Sweetening and soothing role in blends; also marketed for throat and digestion.
Evidence: Some evidence in sore throat and digestive symptoms; the sweetening role is what matters commercially.
What to check: Glycyrrhizin content per serving, which varies enormously between root grades.
Cautions: Glycyrrhizin raises blood pressure and lowers potassium at sustained intakes. The EU and UK set content limits and require warnings for confectionery and some drinks; food supplements containing it are commonly restricted.
Market status: Restricted as a food ingredient in several markets. Confirm the maximum daily glycyrrhizin intake before you put it in a blend.

Ginger and turmeric

Spices & warming roots

Zingiber officinale, Curcuma longa · None

Positioning: Warming, ginger is the top-selling functional tea ingredient; turmeric appears in 'golden' blends.
Evidence: Ginger has reasonable evidence for nausea, including in pregnancy, at culinary-to-moderate doses. Turmeric tea provides very little curcumin compared with an extract.
What to check: Pesticide residues, lead content for turmeric, essential-oil content for ginger, and whether the root is whole, cut or powder.
Cautions: Ginger in high doses may interact with anticoagulants. Turmeric extracts interact with anticoagulants and some chemotherapy agents; culinary amounts are a different exposure.
Market status: Food.

Fennel, anise and star anise

Spices & warming roots

Foeniculum vulgare, Pimpinella anisum, Illicium verum · None

Positioning: Digestive and after-meal blends, and the sweet top note in herbal blends.
Evidence: Traditional use for digestive comfort; limited modern clinical evidence.
What to check: Species verification. Japanese star anise (Illicium anisatum) is toxic and has caused serious poisonings when substituted for Chinese star anise — insist on species confirmation by a laboratory.
Cautions: Estragole in fennel and anise is a genotoxic concern and is limited in food in the EU. Fennel and anise are not recommended for infants as teas in several jurisdictions.
Market status: Estragole limits apply in the EU. Species authentication is a genuine safety control, not a formality.

Chrysanthemum, goji and jujube

Fruit, floral & spice

Chrysanthemum morifolium, Lycium barbarum, Ziziphus jujuba · None

Positioning: The core of Chinese-style wellness and 'office tea' blends: eye comfort, calm, sleep.
Evidence: Mostly traditional use supported by small trials; keep claims modest.
What to check: Pesticide residues and heavy metals, which are the recurring problem for these crops; origin and species verification.
Cautions: Goji can interact with warfarin and with diabetes medication. An allergy risk exists for people sensitive to related plants.
Market status: In China these materials sit in the food, 代用茶 (substitute tea) or health-food framework depending on claims and form. In the EU and US they are foods unless a claim crosses into medicine.

Holy basil (tulsi)

Adaptogens & roots

Ocimum tenuiflorum · None

Positioning: Adaptogen positioning in wellness and 'clarity' blends.
Evidence: Small trials on stress markers; evidence is early-stage.
What to check: Species, harvest part, and the regulatory position — this is one of the botanicals with a novel-food question in the EU.
Cautions: May affect blood sugar and blood clotting. Not for use in pregnancy.
Market status: Novel food status must be checked in the EU and UK before use. Assume it needs verification rather than assuming the market tolerance.

Yerba mate and guarana

Adaptogens & roots

Ilex paraguariensis, Paullinia cupana · Yerba mate approx. 30–50 mg per 200 ml; guarana is a concentrated caffeine source

Positioning: Energy and appetite-suppressant blends.
Evidence: Caffeine effects dominate. Other claimed benefits are not well established.
What to check: Caffeine content per serving on the finished blend, and PAH (polycyclic aromatic hydrocarbon) testing for yerba mate, which is dried with smoke in some processes.
Cautions: High caffeine content, so mandatory warnings apply in the EU and UK above defined thresholds. Not for children or in pregnancy.
Market status: Caffeine labelling thresholds and warnings differ by market. Compute the caffeine per serving of the finished blend, not just per ingredient.

Senna

Stimulant 'detox' botanicals

Senna alexandrina (Cassia angustifolia) · None

Positioning: The active behind almost every 'detox', 'slimming' and '14-day flat tummy' tea.
Evidence: A stimulant laxative with a real pharmacological effect — which is precisely why it should not be a casual daily drink.
What to check: Hydroxyanthracene derivative content per serving. In the EU, these compounds are restricted in food, and in several member states senna is a herbal medicine rather than a food ingredient.
Cautions: Stimulant laxatives cause cramping, diarrhoea and electrolyte loss, and are not intended for prolonged use. They can be dangerous in pregnancy, in children, and for anyone with inflammatory bowel disease or kidney problems. 'Detox' marketing is not a safety assessment.
Market status: In the EU and several other markets, senna and similar hydroxyanthracene materials are regulated as medicines or restricted as food. Selling a 'slimming tea' containing senna may be a medicine authorisation issue, not a labelling issue.

Cascara sagrada and aloe latex

Stimulant 'detox' botanicals

Frangula purshiana, Aloe spp. · None

Positioning: Historic laxative ingredients still found in older 'detox' formulations.
Evidence: Laxative effect is established; there is no credible evidence for the detoxification claims built on top of it.
What to check: Hydroxyanthracene content, and whether the material is permitted as food in the destination market at all.
Cautions: Same profile as senna, with additional concerns. Cascara was removed from permitted food use in the United States.
Market status: Restricted or prohibited as a food ingredient in multiple markets. Verify before including it in anything.

Dandelion, burdock and milk thistle

Stimulant 'detox' botanicals

Taraxacum officinale, Arctium lappa, Silybum marianum ·

Positioning: The 'liver and detox' language in tea marketing.
Evidence: Milk thistle (silymarin) has been studied in liver conditions with mixed results. The concept of a tea 'detoxifying' the liver is not established.
What to check: Species and part used, pesticide residues, and whether any claim on the pack implies treatment of a liver condition — that would make it a medicine.
Cautions: Burdock and dandelion are diuretic and may interact with diuretics and lithium. Anyone with liver symptoms needs a diagnosis, not a tea.
Market status: Food in most markets, but the claims usually written on these packs would make the product a medicine in the EU, UK, Australia and elsewhere.

Comfrey

Stimulant 'detox' botanicals

Symphytum spp. · None

Positioning: Removed from most modern tea ranges, and for good reason.
Evidence: No credible benefit as an infusion; the safety issue is the point.
What to check: Whether the ingredient appears at all in a supplier's formula, and in what part — root and leaf differ.
Cautions: Contains pyrrolizidine alkaloids, which are hepatotoxic. Oral use is prohibited or restricted in many markets and is not considered safe.
Market status: Oral use is banned or restricted in the EU, US, Canada, Australia and elsewhere. Mentioned here so buyers know why it should not appear in a blend.

Tea by market

Herbal infusions fail on a different set of rules from capsules and creams: novel-food status, hydroxyanthracene limits, caffeine thresholds, pesticide residues on a crop that is brewed rather than eaten, and claim wording that quietly turns a drink into a medicine.

Market	What matters most for tea
United States	Tea and herbal infusions are foods, and a tea marketed as a supplement is a dietary supplement. Cascara is not permitted for food use. Stimulant-laxative 'detox' teas have attracted warning letters for unapproved drug claims. Caffeine must be declared on dietary supplement labels and on conventional foods where it is added.
European Union	Tea is a food. Hydroxyanthracene derivatives — senna, cascara, aloe latex, rhubarb root — are restricted in food with a daily intake limit, and in several member states senna is a herbal medicine instead. Botanicals without a consumption history before 1997 need a novel-food authorisation, which is the usual trap for tulsi and newer adaptogens. Estragole limits apply to fennel and anise, and EU pesticide MRLs for tea are enforced at import, so residue testing is a commercial necessity rather than a formality.
United Kingdom	Retained EU rules with UK-specific maximum levels, and the FSA maintains the novel food register. The same hydroxyanthracene restrictions apply, and caffeine above defined thresholds requires a warning.
Australia	A tea making a therapeutic claim becomes a listed complementary medicine with an AUST L number, and the permissible ingredient limits apply — several laxative herbs are restricted. Imported tea is checked for pesticide residues and contaminants.
Canada	Herbal teas are foods unless a health claim is made. Marketing with a health claim or in a dosage form brings the product under the natural health product framework with a product licence. Caffeine labelling rules apply to products with added caffeine.
Japan	Tea is a beverage. Functional claims require either Foods with Function Claims notification or FOSHU approval, so a 'fat-burning' or 'detox' claim cannot simply be printed. Laxative slimming teas are a recurring enforcement target.
China	代用茶 (substitute tea) is a defined food category with its own national standard, and functional claims move the product into health food territory, which requires registration or filing. Botanicals must sit on the approved lists — the 药食同源 list or the health food ingredient list. Imported tea needs GACC registration and a Chinese label.
Singapore	Tea is treated as a food. Claims are restricted, certain substances are prohibited outright, and imported products must carry compliant labelling. Health supplements have a low barrier to entry but the importer carries responsibility.
United Arab Emirates	Tea is a food product requiring registration for import, with Arabic labelling and shelf-life rules. Health claims are restricted, and any functional positioning needs to be cleared as part of registration.
Brazil	Tea is a food. ANVISA permits or restricts specific botanicals, claims are restricted, and Portuguese labelling with a local legal representative is mandatory.

Where to verify the rules

European Commission and EFSA — novel food catalogue, hydroxyanthracene derivatives, pesticide MRLs. food.ec.europa.eu
UK Food Standards Agency — novel food register and maximum levels. food.gov.uk
US FDA — dietary supplement and food labelling, warning letters on detox products. fda.gov
Australia TGA — permissible ingredients for listed medicines. tga.gov.au
China SAMR — 代用茶 and health food frameworks. samr.gov.cn

Tea reference questions

How much caffeine is in a cup of tea?

It varies enormously with leaf grade, water temperature, steep time and whether the leaf is cut. As a working range for a 200 ml cup: green tea roughly 25–50 mg, black tea 30–60 mg, oolong 20–45 mg, matcha 50–70 mg because the whole leaf is consumed, and herbal infusions none. If caffeine content is on your label, measure the finished product rather than adding up ingredient averages.

Why are 'detox' teas treated so seriously here?

Because most of them work the way a laxative works, and because that effect is marketed as gentle self-care. Senna, cascara and aloe latex contain hydroxyanthracene derivatives, which are restricted in food in the EU with a daily limit and are medicines in several countries. The realistic outcome for a daily drinker is cramping, diarrhoea and electrolyte loss — and for the seller, either a medicine authorisation problem or a recall.

Which tea botanicals most often trip up a launch?

Senna and cascara (medicine or restricted food), comfrey (pyrrolizidine alkaloids, oral use prohibited or restricted), licorice (glycyrrhizin limits and warnings), tulsi (novel-food question in the EU and UK), fennel and anise (estragole limits), and yerba mate (polycyclic aromatic hydrocarbons from smoke drying, plus high caffeine).

Is loose leaf better than a tea bag?

Loose leaf usually gives better flavour because the leaf pieces are larger and the infusion is controlled by the drinker, and it is cheaper per gram. A bag is more convenient and more consistent. Neither is inherently healthier, and a premium-looking pyramid bag can contain exactly the same dust as a flat bag. Look at what the pack says about grade, origin and harvest rather than the shape of the bag.

Tea & infusion reference

All tea botanicals

Tea by market

Where to verify the rules

Tea reference questions

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Read a tea label honestly

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