Theaflavin: Overview, Uses, Side Effects, Precautions, Interactions, Dosing and Reviews

Overview

Theaflavin is a chemical in black tea that is formed from fermentation of green tea. It is used as medicine.

People take theaflavin for high levels of cholesterol or other fats (lipids) in the blood (hyperlipidemia), heart disease, obesity, and cancer, but there is no good scientific evidence to support these uses.

Theaflavin has antioxidant, antiviral, and anti-cancer effects in test tube experiments and in animals. Theaflavin might also normalize blood sugar levels. The effects of theaflavin in humans are not well studied.

How does it work ?

Theaflavin has antioxidant, antiviral, and anti-cancer effects in test tube experiments and in animals. Theaflavin might also normalize blood sugar levels. The effects of theaflavin in humans are not well studied.

Uses & Effectiveness

Insufficient Evidence for

High levels of cholesterol or other fats (lipids) in the blood (hyperlipidemia). Early research shows that taking a green tea extract with extra theaflavin seems to help reduce cholesterol.
Heart disease.
Cancer.
Other conditions.

More evidence is needed to rate the effectiveness of theaflavin for these uses.

Side Effects

When taken by mouth: Theaflavin is LIKELY SAFE in the amounts found in brewed black tea. Theaflavin is POSSIBLY SAFE in the amounts found in medicine when used for up to 12 weeks.

Special Precautions and Warnings

When taken by mouth: Theaflavin is LIKELY SAFE in the amounts found in brewed black tea. Theaflavin is POSSIBLY SAFE in the amounts found in medicine when used for up to 12 weeks.

Pregnancy and breast-feeding: There isn't enough reliable information available to know if theaflavin is safe to use when pregnant or breast-feeding. Stay on the safe side and avoid use.

Interactions

Moderate Interaction

Be cautious with this combination

Medications for diabetes (Antidiabetes drugs) interacts with Theaflavin
Theaflavin might decrease blood sugar. Diabetes medications are also used to lower blood sugar. Taking theaflavin along with diabetes medications might cause your blood sugar to go too low. But more evidence is needed to know if this interaction is a big concern. Monitor your blood sugar closely.

Some medications used for diabetes include glimepiride (Amaryl), glyburide (DiaBeta, Glynase PresTab, Micronase), insulin, pioglitazone (Actos), rosiglitazone (Avandia), chlorpropamide (Diabinese), glipizide (Glucotrol), tolbutamide (Orinase), and others.
Medications moved by pumps in cells (Organic anion-transporting polypeptide substrates) interacts with Theaflavin
Some medications are moved by pumps in cells. Theaflavin might change how these pumps work and decrease how much of some medications get absorbed by the body. This could make these medications less effective.

Some of these medications that are moved by pumps in cells include bosentan (Tracleer), celiprolol (Celicard, others), etoposide (VePesid), fexofenadine (Allegra), fluoroquinolone antibiotics, glyburide (Micronase, Diabeta), irinotecan (Camptosar), methotrexate, nadolol (Corgard), paclitaxel (Taxol), saquinavir (Fortovase, Invirase), rifampin, statins, talinolol, torsemide (Demadex), troglitazone, and valsartan (Diovan).

Dosing

The appropriate dose of theaflavin depends on several factors such as the user's age, health, and several other conditions. At this time there is not enough scientific information to determine an appropriate range of doses for theaflavin. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult your pharmacist or physician or other healthcare professional before using.

View References

REFERENCES:

Maron DJ, Lu GP, Cai NS, et al. Cholesterol-lowering effect of a theaflavin-enriched green tea extract: a randomized controlled trial. Arch Intern Med 2003;163:1448-53..

Yanagida A, Shoji A, Shibusawa Y, et al. Analytical separation of tea catechins and food-related polyphenols by high-speed counter-current chromatography. J Chromatogr A 2006;1112:195-201.

Tu YY, Tang AB, Watanabe N. The theaflavin monomers inhibit the cancer cells growth in vitro. Acta Biochim Biophys Sin (Shanghai) 2004;36:508-12.

Liu S, Lu H, Zhao Q, et al. Theaflavin derivatives in black tea and catechin derivatives in green tea inhibit HIV-1 entry by targeting gp41. Biochim Biophys Acta 2005;1723:270-81.

Chen CN, Lin CP, Huang KK, et al. Inhibition of SARS-CoV 3C-like Protease Activity by Theaflavin-3,3'-digallate (TF3). Evid Based Complement Alternat Med 2005;2:209-15.

Mizuno H, Cho YY, Zhu F, et al. Theaflavin-3, 3'-digallate induces epidermal growth factor receptor downregulation. Mol Carcinog 2006;45:204-12.

Way TD, Lee HH, Kao MC, Lin JK. Black tea polyphenol theaflavins inhibit aromatase activity and attenuate tamoxifen resistance in HER2/neu-transfected human breast cancer cells through tyrosine kinase suppression. Eur J Cancer 2004;40:2165-74.

Kundu T, Dey S, Roy M, et al. Induction of apoptosis in human leukemia cells by black tea and its polyphenol theaflavin. Cancer Lett 2005;230:111-21.

Fukuda I, Sakane I, Yabushita Y, et al. Black tea theaflavins suppress dioxin-induced transformation of the aryl hydrocarbon receptor. Biosci Biotechnol Biochem 2005;69:883-90.

Jhoo JW, Lo CY, Li S, et al. Stability of black tea polyphenol, theaflavin, and identification of theanaphthoquinone as its major radical reaction product. Agric Food Chem 2005;53:6146-50.

Matsui T, Tanaka T, Tamura S, et al. alpha-Glucosidase inhibitory profile of catechins and theaflavins. J Agric Food Chem 2007;55:99-105.

Cai F, Li CR, Wu JL, et al. Theaflavin ameliorates cerebral ischemia-reperfusion injury in rats through its anti-inflammatory effect and modulation of STAT-1. Mediators Inflamm 2006;2006:30490.

Takemoto M, Takemoto H, Kouno H, Soeda T, Moriya T. A simple, enzymatic biotransformation method using fresh green tea leaves efficiently generates theaflavin-containing fermentation water that has potent physiological functions in mice and humans. Biol Pharm Bull 2017;40(6):860-6. doi: 10.1248/bpb.b17-00062.

Aizawa T, Yamamoto A, Ueno T. Effect of oral theaflavin administration on body weight, fat, and muscle in healthy subjects: a randomized pilot study. Biosci Biotechnol Biochem 2017;81(2):311-5. doi: 10.1080/09168451.2016.1246170.

Fuchs D, de Graaf Y, van Kerckhoven R, Draijer R. Effect of tea theaflavins and catechins on microvascular function. Nutrients 2014;6(12):5772-85. doi: 10.3390/nu6125772.

Henning SM, Aronson W, Niu Y, et al. Tea polyphenols and theaflavins are present in prostate tissue of humans and mice after green and black tea consumption. J Nutr 2006;136(7):1839-43.

Lee MJ, Lambert JD, Prabhu S, et al. Delivery of tea polyphenols to the oral cavity by green tea leaves and black tea extract. Cancer Epidemiol Biomarkers Prev 2004;13(1):132-7.

Kondo A, Narumi K, Okuhara K, et al. Black tea extract and theaflavin derivatives affect the pharmacokinetics of rosuvastatin by modulating organic anion transporting polypeptide (OATP) 2B1 activity. Biopharm Drug Dispos. 2019;40(8):302-306.

Gothandam K, Ganesan VS, Ayyasamy T, Ramalingam S. Antioxidant potential of theaflavin ameliorates the activities of key enzymes of glucose metabolism in high fat diet and streptozotocin - induced diabetic rats. Redox Rep. 2019;24(1):41-50.

Cai X, Liu Z, Dong X, et al. Hypoglycemic and lipid lowering effects of theaflavins in high-fat diet-induced obese mice. Food Funct 2021;12(20):9922-9931.

Wang J, Jiang J, Zhao C, et al. The Protective Effect of Theaflavins on the Kidney of Mice with Type II Diabetes Mellitus. Nutrients 2022;15(1):201.

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