Lower Blood Pressure With Black Tea?

Blood pressure can be reduced by consuming several cups of black tea daily

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) For most with hypertension, blood pressure cutting methods such as reducing salt, avoiding alcohol and exercising are less than thrilling ways to start the day. 

Drinking black tea daily, however, might be welcome news.

Consuming black tea on a daily long-term basis appears to lower blood pressure. This marks the first study to find that consuming leaf tea may lower blood pressure.

"Talk to your doctor about black tea's benefits"

Jonathan Hodgson, a lead study researcher from the University of Western Australia, noted that there could be several explanations for why black tea lowers blood pressure ranging from improved endothelial function, comprised of a thin layer of cells that lines the interior surface of blood vessels and lymphatic vessels related to hypertension, to the presence of tea flavonoids.

Previous research has suggested that such flavonoids in green tea may reduce body weight. The flavonoids in black tea are structurally similar to that of black tea.

During the randomized placebo-controlled double-blind trial, researchers enrolled 95 men and women between the ages of 35 and 75 who were regular tea drinkers. Participants had a body mass index between 19 and 35, and a systolic blood pressure between 115 and 150 mmHg.

During the initial four weeks of the six-month trial, participants drank three cups of regular leaf tea daily and maintained a low flavonoid diet, which was continued throughout the study. Beginning in the second month participants consumed three cups of either 1493 milligrams of powdered black tea containing 429 milligrams of polyphenols and 96 milligrams of caffeine, or a placebo with a similar flavor and caffeine content, but no tea solids containing the polyphenols.

Investigators took blood pressure measurements at the beginning of the study, and again at three months and six months.

They found that drinking black tea regularly could reduce both systolic and diastolic blood pressure by 2 to 3 mmHg. The 24-hour ambulatory blood pressure readings showed that daytime blood pressure levels were significantly lower than measurements taken at night, accounting for most of the blood pressure drop.

Researchers suggested that regular black tea consumption could significantly lower blood pressure for individuals in the normal to high-normal range, potentially cutting the prevalence of high blood pressure by 10 percent and reducing the incidence of heart disease by up to 10 percent.

The study was published in the Jan. 23 edition of journal Archives of Internal Medicine.

Reviewed by: 
Review Date: 
January 23, 2012
Last Updated:
January 24, 2012