High blood pressure, also known as hypertension, is a common health problem that affects millions of people around the world. It increases the risk of heart disease, stroke, and other serious conditions.
Many people try to manage it with medication, but there is also growing interest in natural ways to help control blood pressure.
A recent study from the University of Bonn has found that something very simple—an extract from red onion skin—may help lower blood pressure in people who are overweight or obese. This finding is interesting because onion skin is usually thrown away, yet it may contain helpful compounds for human health.
The key ingredient in this extract is a natural compound called quercetin. Quercetin is found in many fruits and vegetables, such as red onions, apples, kale, and capers. It belongs to a group of plant substances called flavonoids, which are known for their health benefits, especially for the heart.
Scientists have been studying quercetin for many years. Earlier research suggested that it may help protect the heart and reduce blood pressure. However, more clear evidence from human studies was needed. This new study aimed to better understand how quercetin works in people who already have higher blood pressure levels.
The researchers focused on individuals who were overweight or obese and had either pre-hypertension or stage I hypertension. These are early stages of high blood pressure, where lifestyle changes and treatment can make a big difference.
In total, 70 people took part in the study. They were divided into two groups. One group received a daily supplement containing 162 milligrams of quercetin taken from red onion skin extract. The other group received a placebo, which looked the same but did not contain the active ingredient.
The study lasted for six weeks. During this time, the researchers carefully measured the participants’ blood pressure before and after the treatment period. They also monitored blood pressure during the day and at night to get a full picture of any changes.
The results showed that quercetin had a clear effect, especially in people who already had high blood pressure. In this group, systolic blood pressure—the top number in a blood pressure reading—dropped by an average of 3.6 mmHg compared to the placebo group.
The study also found that quercetin helped reduce both daytime and nighttime blood pressure levels. This is important because high blood pressure at night is linked to a higher risk of heart problems.
However, the researchers did not find changes in other health markers. Quercetin did not appear to affect cholesterol levels, blood sugar, inflammation, or oxidation in the body. This suggests that its main benefit in this study was related to lowering blood pressure rather than improving overall metabolic health.
Even though the effect may seem small, a reduction in blood pressure of just a few points can make a meaningful difference over time. Lower blood pressure can reduce the risk of heart disease and stroke, especially when combined with other healthy habits.
The researchers concluded that taking a daily supplement of quercetin from red onion skin extract may offer a simple and natural way to support heart health. However, they also noted that more studies are needed to confirm these findings and to understand how quercetin works in different groups of people.
In addition to quercetin, other natural approaches may also help manage blood pressure. Some studies suggest that drinking tea, using certain herbal supplements, reducing added sugar, and maintaining good vitamin D levels may support healthy blood pressure. Regular exercise and a balanced diet are also very important.
This study was led by Verena Brüll and her team, and the results were published in the British Journal of Nutrition. It adds to growing evidence that natural compounds found in everyday foods may have real health benefits.
For people looking for simple ways to improve their health, this research offers an encouraging message. Even small changes, such as adding more plant-based foods to the diet, may help support the heart and reduce the risk of disease.
If you care about blood pressure, please read studies about unhealthy habits that could increase high blood pressure risk, and people with severe high blood pressure should reduce coffee intake.
For more information about blood pressure, please see recent studies that early time-restricted eating could help improve blood pressure, and results showing plant-based foods could benefit people with high blood pressure.
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