The unexpected ways vaccines could boost your health

Subscribe to enjoy similar stories. Despite being among the great scientific breakthroughs of all time, vaccines are under fire as top government officials cast doubts on their safety. But as doctors and vaccine deniers spar over the safety of vaccines, emerging evidence finds that some vaccines aren’t only good at preventing the disease or virus they target but also might have broader or even unrelated health benefits.

Health Secretary Robert F. Kennedy Jr. has raised questions about numerous vaccines and taken steps to make it easier for parents to opt out of vaccinating their children.

And in its strongest antivaccine move to date, a federal vaccine panel Friday voted to scrap a recommendation that all newborns get the hepatitis B vaccine. While the focus has been on childhood vaccines, researchers are studying whether certain adult vaccines can be used for dementia prevention or for improving cancer survival rates. The shingles vaccine, for example, might help reduce the risk of developing dementia later.

The Covid-19 vaccine, when given to certain cancer patients, increased their survival rates, one recent study found. An old tuberculosis vaccine—bacillus Calmette-Guérin, or BCG—is being studied to prevent Alzheimer’s disease. It has also been shown to decrease infant mortality in parts of the developing world where it is still widely used.

It is a concept known as trained immunity. Adaptive immunity trains the immune system to recognize a specific pathogen. Trained immunity is a form of innate immune memory whereby the body generates a more robust response to even unrelated exposures.