# Keemun Hao Ya (Camellia sinensis)

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/keemun-hao-ya
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-03-24
**Evidence Score:** 2 / 10
**Category:** Tea Cultivars
**Also Known As:** Camellia sinensis var. sinensis, Qimen Hao Ya, Keemun Superior, 祁门毫芽, Chinese Black Tea, Anhui Black Tea, Qimen Red Tea

## Overview

Keemun Hao Ya (Camellia sinensis) is a premium black tea cultivar containing high concentrations of theaflavins and catechins that support metabolic health through lipid [metabolism](/ingredients/condition/weight-management) modulation. Research demonstrates its ability to reduce body weight and triglyceride levels while providing potent [antioxidant protection](/ingredients/condition/antioxidant).

## Health Benefits

• May support healthy weight management - animal studies showed reduced food intake, body weight, and blood triglyceride levels in diet-induced obesity rat models
• Demonstrates potent [antioxidant activity](/ingredients/condition/antioxidant) - in vitro studies confirmed high-grade teas showed superior DPPH, FRAP, and total reducing capacity without cytotoxicity to normal cells
• May support gastrointestinal health - animal studies found high-grade KBT prevented epithelial barrier damage and reduced pro-[inflammatory](/ingredients/condition/inflammation) markers in ulcerative colitis models
• Modulates hepatic enzyme activity - animal research showed activation of PXR-CYP3A4 pathway and regulation of drug-metabolizing enzymes
• May enhance [gut microbiome](/ingredients/condition/gut-health) balance - animal studies demonstrated increased Firmicutes/Bacteroidetes ratio and enhanced short-chain fatty acid production

## Mechanism of Action

Keemun Hao Ya's theaflavins and catechins modulate lipid metabolism by inhibiting pancreatic lipase and fatty acid synthase enzymes, reducing dietary fat absorption and lipogenesis. The polyphenols activate AMPK pathways, enhancing [fat oxidation](/ingredients/condition/weight-management) while suppressing appetite through leptin sensitivity improvement. Antioxidant activity occurs via direct [free radical scaveng](/ingredients/condition/antioxidant)ing and upregulation of endogenous antioxidant enzymes like catalase and [glutathione](/ingredients/condition/detox) peroxidase.

## Clinical Summary

Animal studies in diet-induced obese rats demonstrated significant reductions in food intake, body weight, and blood triglyceride levels following Keemun Hao Ya supplementation. In vitro [antioxidant](/ingredients/condition/antioxidant) assays confirmed superior DPPH radical scavenging, FRAP values, and total reducing capacity compared to lower-grade teas. Current evidence is primarily preclinical, with no published human clinical trials specifically examining Keemun Hao Ya's metabolic effects. The antioxidant data comes from laboratory studies measuring standardized antioxidant capacity markers.

## Nutritional Profile

Keemun Hao Ya is a high-grade Chinese black tea (fully oxidized) with a nutritional profile dominated by bioactive polyphenols rather than macronutrients, as it is consumed as a brewed beverage. Per 100ml brewed tea (approximate): Calories: 1-2 kcal; Protein: <0.1g; Carbohydrates: 0.2-0.3g; Fat: 0g; Fiber: 0g (negligible in liquid form). Key bioactive compounds include theaflavins (0.3-1.8% dry leaf weight) and thearubigins (10-20% dry leaf weight), which are the primary oxidized polyphenols formed during black tea processing and responsible for its [antioxidant activity](/ingredients/condition/antioxidant) confirmed via DPPH, FRAP, and total reducing capacity assays. Residual catechins including EGCG (epigallocatechin gallate), EGC, ECG, and EC are present at reduced levels compared to green tea (approximately 3-10% of dry leaf weight combined) due to oxidation. Caffeine content: approximately 40-70mg per 240ml serving (2-3% of dry leaf weight). L-theanine: approximately 5-25mg per serving, contributing to umami character. Theophylline and theobromine present in minor quantities (<1mg/serving). Minerals per 240ml brewed cup: Manganese 0.4-0.9mg (a notable micronutrient in tea), Potassium 70-90mg, Fluoride 0.1-0.5mg, Magnesium 5-7mg, Calcium 2-5mg. Vitamins: trace amounts of B vitamins (B2/riboflavin ~0.01mg per cup) and Vitamin K (~0.02mcg per cup). Keemun Hao Ya, as a top-grade (Hao Ya A or B) Keemun, is characterized by higher concentrations of polyphenols and aromatic compounds (including methyl salicylate contributing to its wine-like fragrance) relative to lower-grade Keemun. Bioavailability note: theaflavins and catechins have moderate bioavailability (~20-50% absorption), enhanced when consumed without milk (milk proteins bind polyphenols, reducing absorption). The triglyceride-lowering and weight management effects observed in animal studies are attributed primarily to the theaflavin and thearubigin fraction.

## Dosage & Preparation

Animal studies utilized KBT polyphenol extracts at 75-300 mg/kg body weight orally, while in vitro studies used 100-300 μg/mL concentrations. No human dosage recommendations are available from clinical trials. Consult a healthcare provider before starting any new supplement.

## Safety & Drug Interactions

Keemun Hao Ya contains 40-70mg caffeine per cup, which may cause [insomnia](/ingredients/condition/sleep), jitteriness, or increased heart rate in sensitive individuals. The tea's tannins can reduce iron absorption when consumed with meals, potentially problematic for those with iron deficiency. May interact with anticoagulant medications due to vitamin K content and could enhance stimulant effects of other caffeine sources. Pregnant and breastfeeding women should limit intake to 1-2 cups daily due to caffeine content.

## Scientific Research

Current research on Keemun Hao Ya consists primarily of animal models and in vitro studies, with no human clinical trials identified in the available literature. Key studies include diet-induced obesity rat models showing metabolic benefits, DSS-induced ulcerative colitis mice models demonstrating gastrointestinal protection, and cell culture experiments confirming [antioxidant](/ingredients/condition/antioxidant) capacity without cytotoxicity.

## Historical & Cultural Context

Keemun black tea is described as a 'classic Chinese black tea with exquisite quality' that has been traditionally classified into seven distinct grades. While the research confirms its cultural importance in Chinese tea tradition, specific traditional medicinal applications were not documented in the available studies.

## Synergistic Combinations

Green tea extract, L-theanine, Quercetin, Milk thistle, [Probiotic](/ingredients/condition/gut-health)s

## Frequently Asked Questions

### How much caffeine is in Keemun Hao Ya tea?

Keemun Hao Ya contains approximately 40-70mg of caffeine per 8-ounce cup, similar to other black teas but less than coffee. The exact amount varies based on steeping time, with longer brewing increasing caffeine extraction.

### What makes Keemun Hao Ya different from regular black tea?

Keemun Hao Ya is a premium grade with higher concentrations of theaflavins and catechins compared to standard black teas. Studies show it demonstrates superior antioxidant activity in DPPH and FRAP assays, indicating greater bioactive compound density.

### Can Keemun Hao Ya help with weight loss?

Animal studies suggest Keemun Hao Ya may support weight management by reducing food intake and body weight in obese rat models. However, human clinical trials are needed to confirm these metabolic benefits and determine effective dosages for weight loss.

### When is the best time to drink Keemun Hao Ya for benefits?

Consuming Keemun Hao Ya between meals maximizes antioxidant absorption while avoiding iron interference from food. Morning consumption provides metabolic benefits throughout the day, while avoiding evening intake prevents caffeine-related sleep disruption.

### Are there any side effects of drinking Keemun Hao Ya daily?

Daily consumption is generally safe for healthy adults, but excessive intake may cause caffeine-related side effects like anxiety or insomnia. The tannins can reduce iron absorption, so those with iron deficiency should consume it away from iron-rich meals or supplements.

### Is Keemun Hao Ya safe for pregnant or breastfeeding women?

While Keemun Hao Ya contains lower caffeine levels compared to other black teas, pregnant and breastfeeding women should consult their healthcare provider before regular consumption, as caffeine intake during pregnancy is generally recommended to be limited. Most health authorities suggest pregnant women restrict caffeine to under 200mg daily, and moderation is key if choosing to consume this tea during these periods.

### Does Keemun Hao Ya interact with blood pressure or heart medications?

Keemun Hao Ya contains caffeine and bioactive compounds that may interact with certain cardiovascular medications, beta-blockers, or blood pressure regulators. If you are taking prescription medications for heart health or hypertension, consult your healthcare provider before adding this tea to your daily routine to avoid potential interactions.

### What is the evidence quality for Keemun Hao Ya's antioxidant benefits in humans?

Current evidence for Keemun Hao Ya's antioxidant benefits is primarily from in vitro studies and animal models showing superior DPPH and FRAP antioxidant capacity compared to lower-grade teas. While these results are promising, human clinical trials specifically examining Keemun Hao Ya's antioxidant effects are limited, so the strength of evidence for direct health benefits in people remains moderate.

---

*Source: Hermetica Superfoods Ingredient Encyclopedia — https://ingredients.hermeticasuperfoods.com*
*License: CC BY-NC-SA 4.0 — Attribution required. Commercial use: admin@hermeticasuperfoods.com*