New Research Says Flu Shots May Reduce Your Risk of Developing Alzheimer's Disease

close up of senior asian woman getting covid 19 vaccine in arm for coronavirus immunization by a doctor at hospital elderly healthcare and illness prevention concept
Can a Flu Shot Help Prevent Dementia?d3sign - Getty Images
  • Recent studies show that vaccines — including those for flu, shingles and pneumonia — are associated with a lower risk of developing dementia.

  • Currently, an estimated six million people in the U.S. live with Alzheimer’s disease or a related form of dementia, such as Lewy body disease or frontotemporal dementia.

  • There is no known cure for Alzheimer's, so understanding the risk factors as well as possible preventative measures is the best approach to combating the diseases that cause cognitive decline.

There have always been a lot of good reasons to stay up to date on your vaccines: Illnesses like influenza, COVID and pneumonia can be debilitating and dangerous — not to mention, they make life just plain miserable.

But now there’s another very compelling reason: These vaccines may also help keep your brain healthy from the ravishes of dementia. "There have been recent studies suggesting that influenza and pneumonia vaccines are associated with lower risk of cognitive decline as we age," says Heather M. Snyder, Ph.D., the vice president of medical and scientific relations at the Alzheimer’s Association.

The latest study to make this connection was published this fall in the Journal of Alzheimer's Disease by researchers at the University of Texas Health Science Center. They looked at the vaccination records of more than 1.6 million patients age 65 and older and found that those who had received a Tdap vaccine (which protects against tetanus, diphtheria and pertussis/whooping cough), a shingles vaccine and/or a pneumococcal vaccine experienced a significant reduction in their risk for developing Alzheimer's within the next eight years, compared with those who did not receive those vaccines.

The numbers were quite significant: In the study, those who received the Tdap reduced their dementia risk by 30%; the shingles vaccine reduced risk by 25%, and the pneumococcal vaccine by 27%.

This latest study also adds important data to the same team's June 2022 study that noted an association between receiving the influenza vaccine and a 40% decrease in the risk of developing Alzheimer's. A 2021 study from Saint Louis University School of Medicine, published in the journal Vaccine, found a similar association between flu shots and a reduced risk of dementia.

"This is consistent with the hypotheses that vaccinations may reduce risk of dementia by training the immune system and not by preventing specific infectious disease," researchers wrote at the time. "If vaccines are identified as causative factors in reducing incident dementia, they offer an inexpensive, low-risk intervention with effects greater than any existing preventive measure."

What is the connection between the vaccines and dementia?

While this is all exciting news — and yet another good reason to stay on top of the adult vaccine schedule recommended by the CDC — more research needs to be done in order to determine the exact link between vaccines and brain health.

"Work is ongoing now to try to understand this linkage," Dr. Snyder says, pointing out that there are different factors that could possibly be behind the connection. "It could be that vaccinations stimulate our immune systems in a way that has other benefits for our brain health; it could be that individuals who seek and get vaccinations are also taking advantage of other preventative healthcare or engaging in other habits that may be beneficial for their brains; or it could be that there is a more direct connection that vaccinations lower the levels of these infections and there is some relationship with these infections and our brain health."

But with no known cure for Alzheimer's disease — which, along with other types of dementia including Lewy body disease and frontotemporal dementia, is expected to triple to affecting more than 150 million people by the year 2050 — it is important to explore every possible way to lower your risk.

What causes diseases like Alzheimer’s?

Alzheimer's is the most common form of dementia, with the Alzheimer’s Association reporting that Alzheimer's disease accounts for 60 to 80% of dementia cases. Currently, there is no specific known cause for dementia, but environment and genetics are both associated with diseases like Alzheimer's.

"In Alzheimer's, more than 100 variations of genes are associated with increased or decreased risk of the disease," Dr. Snyder explains. "These genes impact your risk, but — in almost all cases — they are not a cause by themselves." Other aspects of our wellness can increase the risk of dementia: "Things like our heart and metabolic health are associated with later life risk, as are sleep quality, unhealthy habits like smoking and more," she adds.

Are there other ways to address the risk factors for Alzheimer's and other types of dementia?

Dr. Snyder cautions that "while there is no specific recipe today to reduce your risk, there are habits you can adopt that may be associated with lower risk." In addition to keeping up with vaccines, a brain-healthy lifestyle includes:

  • Staying active. "Find something you enjoy doing, that you are able to do and that you'll keep doing that gets your heart rate up," Dr. Snyder advises.

  • Getting enough sleep. Be sure to follow good sleep hygiene habits, like keeping your bedroom dark, cool and quiet; avoiding computers, phones and other screens before bed; and limiting caffeine to early in the day.

  • Taking care your overall health. Remember that whatever is good for your heart is also good for your brain. Diet and nutrition, which play a vital role in your overall wellness, have also been associated with brain health. For example, getting your daily intake of choline — a nutrient found in meat, poultry, fish and also vegan-friendly products such as mushrooms and legumes — has been shown to reduce the risk of dementia.

You Might Also Like