Does Tea Speed Up Your Metabolism?

Tea is made from steeping the leaves of the Camellia sinesis shrub in water. Hot or cold, tea is second only to plain water as the most popular beverage in the world. Catechins in some forms of tea may boost metabolism, aiding in weight reduction and fat loss.

Catechins

Catechins are a type of polyphenolic flavanoid compound found in the leaves of the Camellia sinesis or tea shrub. Polyphenol compounds have been demonstrated to raise HDL or beneficial serum cholesterol levels, while reducing LDL or bad serum cholesterol levels, and may also play a role in cancer prevention, according to the University of Maryland Medical Center. These catechin flavanoids may also increase metabolism and help burn fat. However, more clinical studies are needed before medical professionals can determine whether this metabolism boost leads to actual weight loss, according to the Oregon State University Linus Pauling Institute.

Tea Types

White, green, oolong and black tea are all brewed from leaves of the Camellia sinesis shrub; however, the leaves are processed differently before consumption. White and green teas are made from dried, unfermented leaves, while oolong leaves are partially fermented and black tea leaves are fully fermented. The less-processed white and green teas have the lowest caffeine levels and the highest proportion of polyphenol compounds, according to the University of Maryland Medical Center. Studies supporting the proposition that tea boosts metabolism have primarily involved polyphenol extracts from green tea.

Herbal Diet Teas

A number of herbal teas are marketed as contributing to weight loss. These beverages are more appropriately called tisanes rather than tea, as they are brewed from the leaves of plants other than Camellia sinesis. These herbal weight loss tisanes primarily work by having a laxative effect, according to the Columbia University Health Services. This may cause a temporary loss of water weight, but will not boost metabolism or burn fat. If herbal tisanes are substituted for high-calorie sugary beverages, however, they may increase weight loss.

Considerations

Tea may interfere with the body's ability to metabolize certain minerals that are necessary for optimal health. Tannins in tea bind with calcium in the intestines, preventing it from being absorbed into the body to build healthy bones and serve other necessary metabolic functions, according to the Arizona Cooperative Extension. Tannins in tea can also interfere with the absorption of iron and other necessary minerals, according to the Utah State University Medical Library.