Light at night is a threat to the heart
In the evening, you want comfort and soft light, but often there is a phone screen, a night light or a lantern under the window. It seems like a small thing. But scientists from Australia, the UK and the USA are sure that all this can harm our hearts. The brighter the lighting at night, the higher the risk of heart disease. Experts urge us to reconsider our attitude to night light — from the bedroom to the streets of cities.
The study covered almost 89 thousand people. The participants wore special sensors on their wrists that recorded the light level during the week. After that, the data was compared with health records for subsequent years, and the results were alarming.
The brighter the night, the higher the risk of five dangerous diseases at once — from heart attack to stroke. People living in the lightest night environment had a 50% higher risk of heart failure.
The effect was especially pronounced in women and people under 60 years of age. Researchers suggest that the problem is a malfunction of the body’s natural rhythms, the circadian ones. These rhythms control sleep, blood pressure, blood sugar levels, and even mood.
When the light does not let the body know that it is already night, the body is working hard. Blood pressure does not decrease, hormones are not produced properly, and the heart begins to suffer over time.
The findings suggest that we have underestimated the effect of night light too much. Perhaps it’s time to turn on a caring mode — not only for the eyes, but also for the heart. A simple rule: the darker the night, the calmer the body.
Experts suggest reviewing lighting in bedrooms, hospitals, and even on city streets. Sometimes taking care of your health starts with a switch.
Published
July, 2025
Duration of reading
1-2 minutes
Category
Medicine
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