From Iran and Northern Africa to Sri Lanka and the tropics, the answer to lower blood pressure may be growing outside houses, in parks, and around office buildings. It’s the hibiscus flower.
This gorgeous flower, often associated with Hawaii, has been a traditional remedy for high blood pressure in many countries. Most often, the flowers are dried and then steeped in water to make hibiscus tea (or “sour tea” if you are in Iran).
But does this home remedy hold up to scientific scrutiny? Let’s find out.
The Gold Standard Makes the Case…
The research on the use of hibiscus for treating high blood pressure is quite impressive. In one randomized, controlled study, researchers tested to see how hibiscus tea compared to captopril, a well-known pharmaceutical blood pressure medication.1
Researchers divided 75 people with high blood pressure into two groups. The first group drank 16 ounces of hibiscus tea each morning. The second group took 25 mg of captopril twice a day.
At the end of one month, 79% of the participants who drank the tea had a reduction of at least 10 points in their diastolic blood pressure (the bottom number). 84% of the participants in the medication group also saw a reduction of at least 10 points in their diastolic pressure.
That means that the tea worked just as well as the medication. Naturally. The only aspect of this study that could be improved upon would be the small sample size.
Following up on this study, the researchers decided to do a second study to test the effects of hibiscus against lisinopril, another known blood pressure lowering drug, with a larger participant pool.2
In this randomized, double-blind study, researchers divided 193 participants with mild to moderate high blood pressure into two groups. The first received a hibiscus extract, standardized to 250 mg of total anthocyanins (the active component of hibiscus), each day. The second group received 10 mg of lisinopril daily.
At the end of four weeks, those receiving the hibiscus had a statistically significant decrease in blood pressure as compared to the medication group. In fact, they dropped an average of 17 points in their systolic (top number) pressure and 12 points in their diastolic (bottom number) pressure.
Plus, participants who took hibiscus saw their sodium levels decrease, but not their potassium. This is critical, as too much sodium can elevate blood pressure levels, while potassium is needed to keep blood pressure levels in check. Some high blood pressure medications can lower potassium to dangerous levels. And the hibiscus extract was found to be 100% safe and well tolerated.
This is all to say that a gold-standard study deemed the natural treatment not only safe, but more effective than the pharmaceutical. Now, that’s Mother Nature at her best.
As if That Wasn’t Enough…
Lastly, a third randomized, double-blind, placebo-controlled study tested three 240 mL servings of hibiscus tea a day against an innocuous brew in 65 patients with mild to moderate high blood pressure.3
At the end of six weeks, those who drank the hibiscus tea had a statistically greater reduction in systolic blood pressure, as compared to the placebo group. Moreover, the higher a person’s systolic pressure was to begin with, the greater his or her reduction.
The diastolic pressure was also lower in the hibiscus group, but not significantly lower as compared to the placebo group.
Researchers concluded, “These results suggest that daily consumption of hibiscus tea, in an amount readily incorporated into the diet, lowers [blood pressure] in pre- and mildly hypertensive adults.”
Once again, the gold standard strikes gold. Clearly hibiscus tea works to lower blood pressure levels naturally.
So What’s the Catch?
How long do you have to drink hibiscus tea to enjoy it’s blood pressure lowering benefits? Let’s find out.
A randomized, placebo-controlled study from Iran tested the effects of hibiscus tea (called sour tea in their experiment) on 54 patients with moderate high blood pressure.4
Half of the participants drank hibiscus tea while the other group drank an arbitrary warm beverage. After 15 days, those who drank the hibiscus tea had an average of 11.2 percent decrease in systolic pressure and 10.7 percent decrease in diastolic pressure. These reductions were statistically significant when compared to the placebo group.
However, three days after the participants stopped drinking the hibiscus tea, their blood pressure levels began to slowly rise again. Their systolic pressure was elevated by 7.9 percent and the diastolic pressure rose by 5.6 percent from their post-treatment lows.
Again, a gold standard study makes the case for hibiscus tea. But it also shows that you must make the tea part of your daily life to enjoy the blood pressure lowering benefits.