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Frequent viral illnesses in men are linked to the male sex hormone
Last reviewed: 01.07.2025
Recently, experts have found out that the presence of a large amount of testosterone in the male body affects the immune response to flu vaccination. Scientists believe that this is why men are more likely than women to get various infectious diseases.
Experts from Stanford University conducted a series of studies and came to the conclusion that in men whose bodies have elevated testosterone levels, protective antibodies to the flu vaccine are activated significantly more slowly, compared to women, as well as to men whose testosterone levels are significantly lower than required.
The scientists conducted the research over two years during the periods when seasonal vaccination against the flu virus was carried out. Voluntary participants in the study were 34 men and 53 women of different ages. As a result of the examination, the scientists found that the immune response to the flu vaccine in women was an order of magnitude higher than in men. Before the vaccination, the scientists took blood samples from all volunteers, which allowed them to establish how the genes responsible for immunity work in each of the subjects.
As it turned out, the male immune system gave a weaker reaction to the flu vaccination. In men, the level of expression of genes that regulated metabolic processes was usually quite high, and testosterone is responsible for the work of such genes. Further analysis showed that the higher the level of male hormone in the body, the weaker the immune response to inflammation.
By the way, experts have long established that men have a higher risk of getting fungal, parasitic, bacterial infections. It was also found that the male immune system does not react as strongly as the female immune system to vaccination against diseases such as flu, yellow fever, measles, hepatitis and a number of other infectious diseases. A new study by specialists from the United States explains this phenomenon. Women have higher levels of proteins in their blood that are produced by immune cells to detect inflammation and activate the body's defenses. Earlier studies on animals showed that testosterone has anti-inflammatory properties, so it is possible that the male sex hormone has a direct connection with the body's immune response. However, scientists have not been able to establish a connection between the level of anti-inflammatory proteins in the body and the body's response to infection or vaccination against viral diseases. In addition, scientists suggest that it is not testosterone itself that reduces the body's immune response, but the process of interaction with a certain set of genes, which reduces the body's ability to resist and suppress the spread of infection in the body.
This is the first study of its kind to establish a link between hormone levels, gene expression and the human immune response. However, scientists plan to learn how to influence testosterone's ability to suppress the body's immune response to inflammation in the future.
Let us recall that scientists recently stated that excess testosterone causes aggressive and antisocial behavior.
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