Researchers from Tel Aviv University discovered that ultraviolet radiation from the sun can increase romantic passion. Under controlled conditions, both women and men were exposed to UVB (ultraviolet type B) and both genders experienced an increase in romantic passion. Exposure to sunlight can alter the regulation of the human endocrine system, which is responsible for the production of sexual hormones.
Roma Parikh, a PhD student, and Ashchar Sorek, a researcher at the Department of Human Molecular Genetics and Biochemistry of the Sackler Faculty of Medicine led the study. The subjects received UVB phototherapy at the Tel Aviv Sourasky, Ichilov, and Assuta medical centers. This groundbreaking discovery was published in the prestigious scientific journal Cell Reports.
Professor Levy explained:
“It has been known for many years now that ultraviolet radiation from sunlight increases testosterone levels in males, and we also know that sunlight plays a major role in both the behavioral and hormonal regulation of sexuality. However, the mechanism responsible for this regulation remained unknown. Our study enabled a better understanding of this mechanism.”
The experiment was conducted in an animal model. It involved exposing animals to UVB sunrays at wavelengths between 320 and 400 nanometers. The results were dramatic. Female hormone levels increased dramatically, which led to an increase in their fertility and a longer rut season. Males also became more attracted to females and were more open to sexual intercourse.
The second stage involved the researchers removing a protein called “p53” from the skin. This protein is responsible for protecting against DNA damage and activating pigmentation when exposed to sunlight. Prof. Levy and colleagues were convinced that UVB exposure caused the observed behavioral, hormonal and physiological changes in the animals. The protective system also regulates sexuality.
The final stage of the study involved 32 human subjects who completed validated questionnaires about their romantic passion and aggression. Both genders were treated with UVB phototherapy at Tel Aviv Sourasky, Ichilov, and Assuta medical centers. Males also noticed an increase in aggression.
Similar results were obtained when subjects were asked to avoid sun for two days and then to tan for approximately 25 minutes. The release of hormones such as testosterone was higher after exposure to sunlight than one day prior to exposure, according to blood tests. Analyses of data from Maccabi Health Services and Clalit revealed that males saw a rise in testosterone during summer.
Prof. Levy says that the skin has many mechanisms to deal with sunlight radiation. One of these mechanisms is the p53 protein. UV exposure can cause DNA damage, such as skin cancer. Two built-in programs are activated by sunlight to protect DNA from damage. These programs are the DNA repair system, and pigmentation. The degree of sun exposure determines which program is active. The p53 protein regulates DNA damage by activating both of these systems. Our study revealed that the same system activates both the sexual and reproductive systems.
This new discovery by TAU could lead to practical applications such as UVB treatments for hormonal disorders. But, further research is needed before such a breakthrough can be made. Prof. Levy believes that the breakthrough will lead to more discoveries in basic science. “Our findings open many scientific and philosophical questions. As humans, we have no fur, and our skin is thus directly exposed to sunlight. We are only beginning to understand what this exposure does to us, and the key roles it might play in various physiological and behavioral processes. It’s only the tip of the iceberg.”
Link to the article: https://www.cell.com/cell-reports/fulltext/S2211-1247(21)01013-5