Tea polyphenols increase thermogenesis

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Wednesday, March 01, 2006 9:04 am Email this article
AN IN VITRO STUDY using brown adipose tissue from a rat found that a preparation of dried tea leaves increased thermogenesis when used alone and more strongly when combined with ephedrine.

Green tea increases thermogenesis in a dose-dependent fashion

Used alone the tea leave preparation increased thermogenesis 20 to 500% in a dose-dependent fashion.

Equal amounts of caffeine had no effect

Equal concentrations of caffeine had no effect.

(Note: Studies have shown that caffeine increases metabolism.)

Ephedrine plus moderate amounts of green tea increases thermogenesis 400-500%

Combining ephedrine and a moderate concentration of tea leave extract also increased thermogenesis 400 to 500%.

Ephedrine plus an equal amount of caffeine increases thermogenesis 200%

An equal concentration of ephedrine and caffeine increased thermogenesis 200%.

Green tea contains both polyphenols and caffeine

The tea leaves contain both polyphenols (principally catechins) and caffeine.

Although human studies are needed to determine effective dosages in people, it seems worth trying given the health benefits of polyphenols.

Increases in thermogenesis

Increased Thermogenesis (in vitro, that is in a test tube, using rat brown adipose tissue)

• Tealine green tea extract (50 uM) alone increased thermogenesis 20%.
• Tealine green tea extract (100 uM) alone increased thermogenesis 80%.
• Tealine green tea extract (100 uM) combined with ephedrine increased thermogenesis 400-500%.
• Tealine green tea extract (250 uM) alone increased thermogenesis 400-500%.
• Caffeine (50 uM) alone increased thermogenesis 0%.
• Caffeine (100 uM) alone increased thermogenesis 0%.
• Caffeine (100 uM) combined with ephedrine increased thermogenesis 200%.
• Caffeine (250 uM) alone increased thermogenesis 0%.

This suggests that ephedrine plus green tea is more potent at increasing thermogenesis than combining ephedrine with caffeine.

REFERENCE

Dulloo AG, Seydoux J, Girardier L. Tealine and thermogenesis: Interactions between polyphenols, caffeine and sympathetic activity. International Journal of Obesity, May 1996, 20(Supplement 4):71 (abstract 08-178-WA1).

Articles on the same subject can be found here:

• Ephedrine/Ephedra

• Green Tea