New Study Reveals Sunlight Makes Men Hungry, But Not Women

Who knew that sunlight could make you hungry? A lot of researchers, apparently. According to a new report revealed by the Nature Metabolism journal, data suggests that exposure to solar rays makes some people seek food, consume it, and exhibit "food-seeking behavior." But "some people" isn't as general as you might imagine ­— the research suggests those hunger inclinations are based specifically on gender.

The report, published July 11, 2022, reveals the results of a national nutrition survey that spanned three years and incorporated approximately 3,000 participants. The model was adjusted for age and followed both males and females throughout the seasons in an effort to determine if gender accounts for different reactions to ultraviolet sun exposure. Researchers concluded that men do indeed react to solar radiation differently than women. 

Specifically, UV rays make men, not women, hungry — and it fluctuates significantly based on the season. The reason for that is complex and could even change the way we view sun exposure in general.

Sun exposure triggers a hormonal reaction in men

When determining why sunlight makes males hungrier compared to women, it basically comes down to hormones. The Guardian explains that the ghrelin hormone typically boosts appetites in both men and women, but when study participants were exposed to midday sun for 25 minutes, only the men experienced a triggered ghrelin increase in their blood. Women had no increase in the "hunger hormone," likely due to blockage by their oestrogen hormones.

The survey data, analyzed by scientists at Tel Aviv University, found that men ate more during the summer months when sunlight is generally more prominent and exposure higher. Does that mean that exposure to sunlight could make men gain weight? Not necessarily, because the increased food intake equated to only about 300 extra daily calories, per The Times of Israel.

More interesting is the potential impact this information could have on how we view sun exposure. Though skin cancer remains a risk for individuals with excessive exposure to UV rays, a comparatively moderate amount of sunshine could actually provide protection from heart disease, leading to expanded life expectancy, notes The Guardian. Theories revolve around possible benefits such as the skin releasing nitric oxide, which relaxes blood vessels and consequently lowers blood pressure. The ghrelin hormone, which increases in males after sun exposure, is also an anti-inflammatory that could provide additional health benefits.