A recent study has uncovered surprising genetic traits in a group of women known for their incredible diving skills off the coast of South Korea.
These women, called the Haenyeo, have been diving for food in the sea for centuries.
Now, scientists believe that their unique way of life may have shaped their bodies—and even their DNA—in ways that could help treat health problems like high blood pressure.
The Haenyeo are female free-divers who live and work on Jeju Island, located about 80 kilometers south of mainland South Korea. For generations, these women have made a living by diving deep into the ocean—up to 20 meters without any breathing equipment—to collect seafood such as abalone, sea cucumbers, and seaweed.
They spend hours in the water every day, even in freezing winter weather. Most of the women diving today are in their 60s and 70s, and some are even over 80 years old.
Melissa Ilardo, a researcher from the University of Utah, has been studying the Haenyeo to find out what makes them so physically capable. Along with her team, she tested their heart rate and blood pressure, then looked at their DNA. What they discovered was fascinating: the Haenyeo have two genetic changes that might give them an edge when diving.
One of these changes is linked to blood pressure. When people dive and hold their breath, their blood pressure usually goes up. This can be risky, especially during pregnancy, because high blood pressure is linked to serious health problems like preeclampsia.
But the Haenyeo seem to have a gene variation that helps keep their blood pressure lower while diving. In fact, they are over four times more likely to carry this gene change compared to people on the mainland. This may help explain how these women are able to dive safely even while pregnant, something that would be dangerous for many others.
The second genetic difference appears to be related to cold pain. Jeju Island gets very cold in winter, and the sea temperature drops too. Still, the Haenyeo keep diving year-round. They only stay out of the water if the wind is strong enough to pose a safety risk.
Although the researchers didn’t test how much cold the women could endure, they found a gene linked to how the body senses cold pain. This might explain how the Haenyeo can handle freezing conditions so well.
However, genetics is only part of the story. A lifetime of training and practice also plays a huge role. Everyone has a natural “diving reflex”—a response where the heart slows down to save oxygen while underwater.
For most people, the heart slows by about 20 beats per minute. But for the Haenyeo, their heart rate can drop twice as much. This reflex gets stronger the more a person dives, showing how much experience matters too.
The Haenyeo‘s genetic traits are not limited to the divers alone—they’re found in many people living on Jeju Island. But it’s the combination of genes, lifestyle, and lifelong dedication that makes these women so extraordinary.
What’s especially exciting is how this research might help others. High blood pressure is a major cause of strokes and heart disease around the world. If the gene variation found in the Haenyeo helps lower blood pressure, it could one day be used to create new treatments.
Interestingly, Jeju Island has one of the lowest rates of death from stroke in South Korea. Scientists wonder if this special gene is playing a part in that.
In summary, the study showed that Haenyeo women may have two helpful genetic traits—one that helps control blood pressure while diving, and another that may reduce cold sensitivity.
These traits likely developed alongside centuries of intense physical activity in cold ocean waters. While more research is needed, this discovery gives scientists a new path to explore how the human body can adapt and how we might use these natural abilities to treat illness. The story of the Haenyeo is not only inspiring but may also help improve health for people everywhere.
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.
The research findings can be found in Cell Reports.
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