# Camellia sinensis 'Okumidori'

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/camellia-sinensis-okumidori
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-04-01
**Evidence Score:** 2 / 10
**Category:** Tea Cultivars
**Also Known As:** Okumidori tea cultivar, Okumidori green tea, C. sinensis 'Okumidori', Okumidori sencha cultivar, おくみどり

## Overview

Camellia sinensis 'Okumidori' is a Japanese green tea cultivar selectively bred for elevated L-theanine and chlorophyll concentrations, which contribute to its characteristic umami flavor profile and vivid green color. Its bioactive compounds — including catechins such as EGCG and the amino acid L-theanine — follow the same mechanisms documented in broader green tea research, though no cultivar-specific clinical trials have been conducted.

## Health Benefits

• No cultivar-specific health benefits documented - no human clinical trials identified for 'Okumidori'
• General green tea benefits may apply but lack cultivar-specific evidence
• High amino acid content noted for sensory qualities only, not health outcomes
• Chlorophyll content mentioned for color, not therapeutic effects
• Contains standard C. sinensis polyphenols but without Okumidori-specific quantification

## Mechanism of Action

EGCG (epigallocatechin gallate), the predominant catechin in 'Okumidori' as in other green tea cultivars, inhibits catechol-O-methyltransferase (COMT) and modulates Nrf2/ARE antioxidant pathways, reducing [oxidative stress](/ingredients/condition/antioxidant) at the cellular level. L-theanine, present in notably high concentrations in shaded 'Okumidori' leaves, acts as a glutamate receptor partial agonist at NMDA and AMPA receptors while also promoting alpha-wave cerebral activity, contributing to calm alertness. Caffeine co-present in the leaf synergizes with L-theanine by antagonizing adenosine A1 and A2A receptors, an interaction studied in standard green tea but not yet isolated for this specific cultivar.

## Clinical Summary

No human clinical trials have been conducted specifically on Camellia sinensis 'Okumidori' as a distinct cultivar, making cultivar-specific efficacy claims unsupported by direct evidence. General green tea research provides the evidentiary basis: a 2017 Cochrane-adjacent systematic review of green tea extracts in [cardiovascular health](/ingredients/condition/heart-health) drew on trials with sample sizes ranging from 40 to over 1,000 participants, finding modest LDL reductions of approximately 2–5 mg/dL. L-theanine-specific trials (e.g., Kimura et al., 2007, n=16) demonstrated increased alpha-wave EEG activity at 50–200 mg doses, but these used isolated L-theanine rather than whole-leaf preparations from any single cultivar. The evidence base is therefore indirect, extrapolated from green tea as a botanical class, and insufficient to attribute specific health outcomes to 'Okumidori' over any other cultivar.

## Nutritional Profile

Okumidori is a shaded Japanese green tea cultivar processed primarily as gyokuro and matcha, with a nutritional profile reflecting both its genetic background and intensive shading (~20 days pre-harvest). Macronutrients per 100g dry leaf: protein approximately 24–29g (elevated relative to unshaded cultivars due to shade-induced amino acid accumulation), carbohydrates approximately 40–45g (including fiber ~10–12g), fat approximately 5–6g. Bioactive compounds are the primary nutritional distinction: total catechins approximately 100–140mg/g dry weight, somewhat lower than high-catechin cultivars like Yabukita under full sun, with shading further suppressing catechin synthesis — epigallocatechin gallate (EGCG) approximately 40–65mg/g dry weight, epigallocatechin (EGC) approximately 20–35mg/g, epicatechin gallate (ECG) approximately 10–18mg/g, epicatechin (EC) approximately 5–10mg/g. Total theanine (L-theanine) is notably elevated at approximately 2.5–4.5g/100g dry leaf, among the higher ranges for C. sinensis cultivars, directly attributable to shade cultivation inhibiting photodegradation of theanine to catechins. Caffeine approximately 3.2–4.5g/100g dry leaf. Chlorophyll a and b combined approximately 800–1,200mg/100g dry leaf (elevated by shading, contributing to vivid green color in matcha form). Carotenoids including lutein and beta-carotene approximately 100–200mg/100g dry leaf. Vitamin C approximately 150–250mg/100g dry leaf (heat-sensitive; largely degraded in brewed tea). Vitamin K1 approximately 1,000–1,200µg/100g dry leaf. Minerals per 100g dry leaf: manganese approximately 30–50mg, potassium approximately 2,000–2,500mg, fluoride approximately 100–200mg, magnesium approximately 200–250mg, calcium approximately 300–400mg. When consumed as matcha (whole leaf powder), bioavailability of all compounds is substantially higher than steeped tea — catechin intake may be 3–10x greater than from infusion. Theanine bioavailability from aqueous infusion is high (>80%). Catechin bioavailability is moderate and matrix-dependent, improved by absence of milk proteins.

## Dosage & Preparation

No clinically studied dosage ranges specific to 'Okumidori' are available due to absence of human trials. General green tea recommendations (not cultivar-specific) suggest 2-3 cups daily or 200-400 mg catechins, but standardization details for Okumidori extracts or powders are undocumented. Consult a healthcare provider before starting any new supplement.

## Safety & Drug Interactions

Green tea preparations containing 'Okumidori' carry the same safety profile as standard green tea: caffeine content (approximately 20–45 mg per 8 oz serving) may cause [insomnia](/ingredients/condition/sleep), tachycardia, or anxiety in sensitive individuals or at high doses. EGCG at supplemental doses above 800 mg/day has been associated with hepatotoxicity in case reports, though brewed tea at culinary quantities poses minimal risk. Green tea catechins can reduce the bioavailability of certain medications including nadolol and other beta-blockers, as well as iron from non-heme dietary sources, and may potentiate anticoagulants like warfarin at high intake levels. Pregnant individuals are advised to limit total caffeine intake to under 200 mg/day, placing high-volume green tea consumption in a caution category, particularly in the first trimester.

## Scientific Research

No human clinical trials, RCTs, or meta-analyses specific to Camellia sinensis 'Okumidori' were identified in the research. While general green tea studies exist on catechins for metabolic health, no cultivar-specific evidence or PubMed PMIDs are available for this particular variant.

## Historical & Cultural Context

'Okumidori' has no traditional medicine history as it was only registered in 1974, postdating classical Japanese systems like Kampo which use generic C. sinensis. It was developed specifically for modern sencha production focusing on yield and flavor rather than traditional herbal applications.

## Synergistic Combinations

Piperine, Vitamin C, L-theanine, EGCG, Quercetin

## Frequently Asked Questions

### What makes Okumidori different from other green tea cultivars?

'Okumidori' is a Japanese cultivar developed by the National Institute of Vegetable and Tea Science, selected for late budding, high chlorophyll density, and elevated L-theanine levels compared to commodity cultivars like Yabukita. Shading the plants before harvest further amplifies L-theanine accumulation by suppressing its conversion to catechins under UV exposure, resulting in a sweeter, lower-bitterness profile. These differences are primarily sensory and compositional — no clinical data compare health outcomes between 'Okumidori' and other cultivars.

### Does Okumidori green tea have more L-theanine than regular green tea?

Shaded 'Okumidori' leaves can contain L-theanine levels in the range of 2–3% of dry weight, which is on the higher end compared to unshaded cultivars that typically yield 1–2%. However, final L-theanine content in a brewed cup depends heavily on water temperature, steep time, and shading duration — a standard 2 g serving of high-grade 'Okumidori' matcha may deliver 20–40 mg of L-theanine per cup. These figures are compositional estimates; no peer-reviewed pharmacokinetic studies have been published specifically for this cultivar.

### Is Okumidori tea safe to drink every day?

Daily consumption of 'Okumidori' as a brewed tea at typical culinary amounts (1–3 cups per day) is considered safe for healthy adults, consistent with the general safety profile established for green tea over centuries of use and reviewed in modern pharmacovigilance data. Individuals sensitive to caffeine, those taking warfarin or beta-blockers, or those with liver conditions should exercise caution or consult a healthcare provider before consuming large quantities. There are no documented adverse events specific to 'Okumidori' in the published literature.

### Can Okumidori green tea help with focus or anxiety?

The L-theanine in 'Okumidori' may support calm alertness through its partial agonism at NMDA receptors and promotion of alpha-wave brain activity, an effect documented in isolated L-theanine studies at doses of 50–200 mg. The caffeine-L-theanine combination present in the whole leaf has been studied in standardized green tea (not 'Okumidori' specifically), with small crossover trials suggesting improved attention and reduced perceived stress compared to caffeine alone. These findings are plausible but not directly validated for this cultivar.

### How does Okumidori compare to matcha for health benefits?

'Okumidori' is actually one of the cultivars sometimes used to produce premium matcha, meaning comparisons depend on whether the product in question is a whole-leaf matcha or a steeped tea. When consumed as matcha, the entire leaf is ingested, delivering higher total EGCG and L-theanine per serving (roughly 50–70 mg EGCG per gram of matcha powder) versus a steeped infusion where only soluble compounds are extracted. No head-to-head clinical trials compare 'Okumidori'-sourced matcha against other matcha cultivars for any specific health outcome.

### Is Okumidori safe to drink during pregnancy or while breastfeeding?

Okumidori is a Camellia sinensis cultivar and contains caffeine, which should be limited during pregnancy and breastfeeding according to medical guidelines. While green tea is generally considered safe in moderate amounts, pregnant and nursing women should consult their healthcare provider about appropriate consumption limits, as cultivar-specific safety data for Okumidori is not available. Most recommendations suggest limiting caffeine intake to under 200mg daily during pregnancy.

### Can Okumidori green tea interact with medications like blood thinners or stimulants?

Okumidori contains caffeine and catechins that may interact with certain medications, including anticoagulants, beta-blockers, and stimulant medications. The caffeine content can potentiate the effects of other stimulants, while the polyphenol content may affect absorption of some medications. Anyone taking prescription medications should consult their healthcare provider before regularly consuming Okumidori tea.

### What is the recommended daily intake of Okumidori tea for general wellness?

General green tea consumption recommendations suggest 2–3 cups daily for potential wellness benefits, though cultivar-specific dosing guidelines for Okumidori are not established. Since Okumidori is a standard Camellia sinensis variety, typical green tea serving sizes (3–5 grams steeped in 8 oz water) apply. Individual tolerance to caffeine and personal health conditions should guide actual consumption amounts.

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*Source: Hermetica Superfoods Ingredient Encyclopedia — https://ingredients.hermeticasuperfoods.com*
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