Studies show that men increase their appetite when exposed to sunlight, but women do not.

Ultraviolet B waves (UVB) are known to cause inflammation, spots, freckles, and skin cancer, but exposure to UVB on the skin induces food exploration and food intake in men and similar behavior in women. The absence was shown by a research team at Tel Aviv University.

Food-seeking behavior is triggered by skin ultraviolet exposure in males | Nature Metabolism

expert reaction to study looking at sunlight and food intake in male and female mice, cells and people | Science Media Center

The research team analyzed data from a three-year national nutrition survey of about 3,000 people, and found that men were more affected by solar radiation and their seasonal fluctuations than women, and their energy intake during the summer was significant. It was revealed that it will increase to.

Specifically, the energy intake of men was 1875 kcal per day in winter (October-February), while it clearly increased to 2188 kcal in summer (March-September), whereas it was clearly increased in women. Was almost constant at 1475 kcal in winter and 1507 kcal in summer. This shows that only men are affected by seasonal changes.

Men especially had significantly increased intakes of carbohydrates, proteins, fats, sodium, omega 3 fatty acids, zinc and iron.

To investigate the difference in the reaction of men and women to exposure to the sun, the research team asked five men and women aged 18-55 years to shine in the sun for about 25 minutes on a sunny day at noon. Examination of plasma samples obtained before and after the sun revealed that men had increased metabolism of lipids and steroids, while women had decreased metabolism.

Furthermore, when 12 male and 12 female mice were exposed to UVB radiation daily for 10 weeks, significant pigmentation was observed in the ears of both males and females, and males showed changes in metabolism-related proteins compared to females. I found that there were many.

In addition, males who received UVB treatment visited the zone with food more frequently than males who received simulated treatment, but females did not make a significant difference in the number of visits depending on the presence or absence of UVB treatment. thing. This indicates that UVB enhanced the feeding behavior of male mice and did not affect females. In wild-type colonies, chronic UVB exposure significantly increased the weight of male mice. Enhanced eating behavior, or increased appetite, was also confirmed in human males.

The appetite hormone ' ghrelin ' is involved in the regulation of appetite.

The runaway appetite may be due to the hormone 'ghrelin' secreted in the stomach-GIGAZINE

by Viewminder

Music, light, and odor are the controlling factors for ghrelin secretion, but the underlying mechanism is unknown. However, this time, when UVB radiation was applied to human skin, it was found that ghrelin mRNA levels were significantly increased in the subcutaneous adipose tissue of men. In contrast, female subcutaneous adipose tissue was not altered by UVB radiation. These results indicate that exposure to UVB enhances male appetite through ghrelin induction.

The researchers also confirmed that the p53 gene regulates UVB-induced ghrelin expression. Then, a study in mice was conducted to investigate the functional requirements of p53, and it was clarified that deletion of p53 abolished the appetite enhancement by UVB, and ghrelin expression in skin adipocytes induced by p53 was estrogen (female hormone). It was shown that women who have significantly higher estrogen than men have ghrelin expression inhibited and that exposure to UVB has no effect on appetite.

Dr. Duane Mellor of Aston University School of Medicine, who is not involved in the study and has no conflicts of interest, said, 'This data is only a cross-sectional study, so it is not possible to determine whether the same man eats more in the summer than in the winter. 'Comment. He added that it was an interesting study spanning five experiments, and pointed out that 'there are differences in the data and the five jigsaw puzzles cannot be completely assembled.'

'The study deals with the role of the hormone grelin in the skin and how it relates to exposure to the sun or other UV rays,' said Kevin McConway, an endocrinologist at the Open University of the United Kingdom. So, I think it's very interesting and important, but I'm not a specialist in physiology and endocrinology, so I won't comment any further. ' It's consistent with the findings, but I don't think the same thing as the experimental content completely supports the possibility that it's happening in the human body. Focusing on the results of the national survey means that it is irrelevant from the perspective of the entire study, 'he said, skeptical about linking the content of the experiment with the conclusions.

in Science,   Junk Food, Posted by logc_nt