Coffee in the morning, black tea in the afternoon: for many people, that’s the daily routine. But when researchers in Boston put a very different cup to the test, it was linked to lower blood pressure. It’s deep red, a little tart, and you can find it in the tea aisle.
In short
- The drink is hibiscus tea.
- In a Tufts University trial, 65 adults drank 3 cups a day for 6 weeks.
- Their systolic blood pressure fell by 7.2 points, compared with 1.3 points in the placebo group.
- It’s a small study, and it doesn’t replace medical treatment.
The study
The trial was led by Diane McKay at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University in Boston, the USDA’s Agricultural Research magazine reported. The results were published in the Journal of Nutrition in 2010.
McKay’s team recruited 65 volunteers aged 30 to 70 whose blood pressure was either a little above normal, what doctors call prehypertension, or mildly high. For six weeks, half of them drank three cups of hibiscus tea a day. The other half drank a placebo, a beverage with artificial hibiscus flavor and color, so nobody could tell which cup they had.
The results
At the end of the six weeks, systolic blood pressure, the top number, had dropped by 7.2 points on average in the hibiscus group. In the placebo group, it dropped by only 1.3 points.
The effect was larger for people who started higher. Among the 30 volunteers whose systolic reading was 129 or above, systolic pressure fell by 13.2 points and diastolic pressure, the bottom number, by 6.4 points.
The same research center has looked at other popular herbal teas too: McKay and Jeffrey Blumberg, who directs the center’s Antioxidants Research Laboratory, also reviewed the research on chamomile and peppermint teas.
About hibiscus, McKay said that drinking the tea “in an amount readily incorporated into the diet may play a role in controlling blood pressure,” while adding that more research is needed.
Why it’s worth knowing
Three cups a day is a realistic amount, which is exactly McKay’s point: it fits into an ordinary day. For someone looking to swap one of their usual cups of coffee or black tea, hibiscus is an easy option to try, hot or iced.
It belongs to a bigger idea: the foods and drinks with real research behind them aren’t always the famous ones. That’s what a CDC ranking showed with the vegetable that beat kale and spinach. And if you like warm, fragrant drinks at home, there’s also the habit of boiling lemon peels with ginger.
The limit
This was one small trial, with 65 people, over six weeks, and the researchers themselves say more research is needed. The volunteers had slightly or mildly high blood pressure, so the results don’t say what happens in other groups. Hibiscus tea is not a treatment: if you have high blood pressure or take medication for it, talk to your doctor before changing your routine.
That’s the trick.
