ATLANTA (CBS ATLANTA) — Men with higher levels of testosterone are more likely to have very little, or no response to flu vaccines and other defenses against influenza and other infectious diseases.
A new study from Stanford University finds that the flu vaccine is less effective for men than women, and the researchers believe that testosterone causes genes within male immune systems to produce fewer antibodies to defend against the flu.
“Men, typically, do worse than women in immune response to infection and vaccination,” Stanford research associate David Furman, the lead study investigator, told Medicine Net. “We found a set of genes in men that when activated caused a poor response to the vaccine, but were not involved in female response. Some of these genes are regulated by testosterone.”
The study, published Dec. 23 in the Proceedings of the National Academy of Sciences, analyzed the blood of 90 adults after receiving seasonal flu shots. The men with the highest testosterone levels had the worst responses.
The researchers found that genes such as cholesterol manufactured in the liver, combined with high testosterone levels made for a much weaker response to the flu vaccine and other bacterial, viral and parasitic infections.
Testosterone is a steroid hormone present in mammals, reptiles and other species and is the principal male sex hormone associated with characteristics such as muscle strength and beard growth.
According to the Centers for Disease Control and Prevention, influenza is a contagious respiratory illness caused by influenza viruses. It can cause mild to severe illness. Serious outcomes of flu infection can result in hospitalization or death. Some people, such as older people, young children, and people with certain health conditions, are at high risk for serious flu complications.
The CDC recommends that the best way to protect against the flu is to get vaccinated each year.
Women, however, are not in the clear from other diseases despite developing a more robust immune system against infection.
Women are more likely to suffer from autoimmune diseases such as lupus, and are also more susceptible for developing Alzheimer’s disease than their male counterparts.