How can sunlight affect women's reproductive ability?

A pioneering study revealed a positive interaction between UV radiation and fertility in women aged 30 to 40 years.

A research team from Tel Aviv University and Sheba Medical Center conducted a study highlighting seasonal fluctuations in levels of anti-Müllerian hormone (AMH), a valuable marker for assessing a woman's ovarian reserve, which is essentially an indicator of her reproductive potential.

The study revealed that during the summer, women between the ages of 30 and 40 experience an increase in hormone secretion from the ovaries.

The team believes that the cause of this phenomenon may be increased exposure to ultraviolet rays coming from the sun.

Dr. Ruth Persek from the Endocrine Institute at Sheba Medical Center explains: “The ovaries secrete anti-Müllerian hormone, and its level in the bloodstream is linked to ovarian function. Although the hormone level is specific to a particular woman at a particular time and does not provide a final assessment of her fertility status, evaluating "Its value, trend and comparison with age group is the best indicator of fertility we have. For this reason, every woman who wants or is trying to become pregnant is required to take an anti-Müllerian hormone (AMH) test."

The researchers compared the anti-Müllerian hormone (AMH) test results of 2,235 women to their recorded levels of UV radiation.

For younger women aged 20-29, no statistical relationship was found between UV exposure and hormone level.

On the other hand, a statistically significant seasonal pattern emerged among fertile older women aged 30 to 40: those women whose egg reserves were low responded favorably to sun exposure.

Based on previous studies, the team confirmed that “exposure to sunlight increases metabolism, sexual desire, behavior and, at least in animal models, enlarges the ovaries and prolongs the period of estrus,” according to Professor Carmit Levy from the Department of Human Genetics and Biochemistry.

The absence of this effect among younger women in their 20s is particularly interesting. According to Dr. Persek, this may be due to the reserve of eggs that young women have in abundance.

She added: “Based on my interpretation of the results, women at the beginning of childbearing age are less in need of signals from the sun, which affect hormonal pathways that have not yet been adequately studied. They are also less affected or dependent on the forces of nature. In contrast, larger ovaries need We need ideal environmental factors in order to perform its function.

She continued: “In fact, this effect was more pronounced among women aged 35 years or older. Of course, there are caveats: exposure to the sun’s ultraviolet rays should always be done in moderation, and more research is needed to determine whether this exposure actually helps.” on fertility, and the amount of exposure required.”

Excessive exposure to the sun's ultraviolet rays can lead to premature skin aging, suppression of the immune system, and increased risk of skin cancer. Therefore, understanding the optimal level of sun exposure for fertility benefits, without increasing these risks, is crucial.

Study: Excessive protein consumption may cause a sudden stroke

University of Pittsburgh researchers found that high levels of protein consumption may activate cells that clog arteries with plaque, disrupting blood flow and increasing the risk of a sudden stroke.

This comes amid the growing popularity of high-protein diets coupled with exercise instructions.

The research team revealed that once protein is consumed, it is broken down in the body into amino acids that are used to repair torn muscle fibers while helping to grow new ones. But if a person does not exercise, unused proteins will be eliminated from the body by the kidneys and excreted in the urine.

The researchers observed increased activity of a type of white blood cell responsible for removing cellular debris (macrophages) when breaking down high levels of protein, which leads to the accumulation of these cells within the walls of blood vessels and the formation of plaques over time.

The research results showed that consuming large amounts of protein caused an increase in the concentration of a certain amino acid, called leucine, and a slight increase in a substance that activates the immune system.

The research team said that activating more immune cells raises levels of inflammation, which increases the risk of plaques.

In a separate part of the research, the researchers fed mice a high-protein diet and tested their blood, finding a significant increase in leucine levels and in a substance that activates white blood cells.

Research supervisor and cardiologist, Babak Razani, warned that “abundant” protein consumption is not a “magic solution” for a good diet. He suggested a "balanced" diet containing enough carbohydrates, fats and vital nutrients.

“In our mechanistic studies, we showed that amino acids, which are actually the building blocks of protein, can trigger disease through specific signals,” said Dr. Bettina Mittendorfer, a metabolism expert at the University of Missouri. “Little immune cells called macrophages can trigger development of atherosclerosis.

Other researchers who were not involved in the research disputed the results, saying more research was needed.

Dr Brian Williams, medical officer at the British Heart Foundation, said: “Further studies over a longer period of time will help us better understand how protein affects the heart. A healthy diet, which includes eating protein in moderation, is still one of the most important things.” What you can do for heart health.

The study was published in the journal Nature Metabolism.