“Stay out of the sun!” These are often words we hear from the doctors. “It causes cancer”, are the words that usually follow next. And we do what they say – because they’re doctors – and they know best, right?
Maybe not!
A recent study published in The Journal of the American Heart Association cautions us otherwise.
Apparently we need sunlight as it helps keep our blood pressure at healthy levels.
And it isn’t just the vitamin D from UV that helps, that’s just half of it.
The study emerged after researchers discovered two things:
1. Blood pressure readings were lower in places that were sunny.
2. People in the Southern Hemisphere tend to have lower blood pressure than the Northern Hemisphere.
So, what’s the deal?
Clearly there’s a positive connection between sunlight and a healthy blood pressure.
Firstly, vitamin D is responsible. When ultraviolet rays hit your skin, your body converts them into vitamin D. Consequently vitamin D then lowers blood pressure.
Researchers obtained the blood pressure records of 342,457 patients from 2,178 dialysis centers in the United States.
In addition, they obtained UV radiation and temperature data for each clinic’s location from the National Oceanic and Atmospheric Administration.
They then calculated a monthly average blood pressure, a monthly average UV index score, and an average monthly temperature. This enabled them to find the relationships between the variables.
As they expected, they found that their subjects had 3 mmHg lower systolic blood pressure during the sunny season.
The authors cited previous studies that proved a 3-mmHg systolic blood pressure reduction could decrease cardiovascular events by 10 percent.
When they separated temperature and UV exposure, they found that each contributed to about half of the overall effect.
So, it isn’t just vitamin D from UV that lowers blood pressure, it’s also the warm weather.
Regarding the risk of skin cancer, the authors cited numerous studies that proved that it was sunburn that caused skin cancer, and not regular exposure to sunlight.
Getting enough sunlight may not be enough to reduce your blood pressure to normal levels.
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