In an exciting new study, scientists at the University of Bonn have discovered that something as simple as red onion skins might hold the key to lowering high blood pressure—especially for people who are overweight or obese. This natural solution centers on a plant compound called quercetin.
Quercetin is found in many foods we eat every day, such as capers, red onions, kale, and apples. It gives these foods a slightly bitter taste, and it’s also widely used in health products like supplements and wellness drinks. Scientists have been interested in quercetin for years because of its possible health benefits, especially for the heart.
High blood pressure, also known as hypertension, is a major cause of heart disease. Managing it can greatly reduce the risk of strokes and heart attacks. Past research already suggested that quercetin might help lower blood pressure, and this new study offers even stronger evidence.
The research involved 70 people who were either overweight or obese and had high blood pressure. The participants were divided into two groups. One group took a daily dose of 162 milligrams of quercetin, which was extracted from red onion skins. The other group received a placebo—a harmless pill with no active ingredients. This continued for six weeks.
To measure how well the treatment worked, researchers used two methods: regular blood pressure readings taken in the doctor’s office and a special device worn by participants that tracked their blood pressure throughout the day and night.
This second method, called ambulatory blood pressure monitoring, gives a fuller picture of how blood pressure changes during everyday activities.
The results were encouraging. People who took the quercetin supplement had noticeably lower blood pressure compared to those who took the placebo. This drop was seen both during the day and at night, making the findings even more impressive.
However, quercetin didn’t seem to affect other health areas. The study didn’t find changes in cholesterol, blood sugar, inflammation, or stress in the body. This suggests that quercetin’s main strength is in lowering blood pressure, not improving all aspects of heart health.
Still, for people looking for a natural way to manage their blood pressure, quercetin could be a promising option. A daily dose of 162 mg, as used in the study, might offer a simple, natural tool for fighting hypertension—especially for people who don’t respond well to medication or want to avoid side effects.
This study was published in the British Journal of Nutrition by Verena Brüll and her team. It adds to a growing list of studies showing how natural substances in food can benefit our health. Other research has shown that drinking tea, using herbal supplements, cutting added sugar, and getting enough vitamin D might also help reduce high blood pressure.
What makes this new research unique is the idea that something often thrown away—like the skin of a red onion—could actually improve heart health. It’s a reminder that powerful health solutions can sometimes come from the most unexpected places.
This study is a significant step in understanding how natural ingredients like quercetin can support heart health. The results are clear: quercetin from red onion skin helped lower blood pressure in people at high risk. While it didn’t affect other markers like cholesterol or blood sugar, the effect on blood pressure alone is important.
High blood pressure is a major risk for heart attacks and strokes, so any safe and simple way to lower it could benefit millions. More research is needed to see how quercetin works over longer periods or in combination with other lifestyle changes. But for now, this study offers new hope for people looking for natural, food-based ways to improve their heart health.
If you care about high blood pressure, please read studies about unhealthy habits that may increase high blood pressure risk, and drinking green tea could help lower blood pressure.
For more information about high blood pressure, please see recent studies about what to eat or to avoid for high blood pressure, and 12 foods that lower blood pressure.
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