Vaccines help you stay healthy by preventing infections including shingles, RSV and the flu. But there’s something more those routine shots might do: They might protect your brain as you age.
Research suggests that the rate of Alzheimer’s disease and other types of dementia is lower in people who get routine vaccinations for shingles and other common infections.
“The finding is intriguing but not entirely surprising,” says Angelos Katramados, M.D., a neurologist at Henry Ford Health. Over the past decade, he says, a growing body of evidence has linked the immune system to long-term brain health.
Dr. Katramados explains what the research suggests and what it reveals about protecting the brain.
The Link Between Vaccines and Alzheimer’s Disease
Scientists recently reviewed more than 20 studies that compared dementia rates across more than 100 million people. They found that the shingles vaccine was associated with a 24% lower risk of any type of dementia.
For Alzheimer’s disease, the most common type of dementia, there was a 47% lower risk in people who had the shingles vaccine. The study also found evidence that the flu, pneumococcal, and Tdap (tetanus, diphtheria and pertussis) vaccines might also reduce the risk of Alzheimer’s disease and other types of dementia.
It’s a notable finding, but it’s not the end of the story just yet. “We cannot say that shingles vaccine is proven to decrease dementia,” Dr. Katramados cautions.
It’s possible that people who are more likely to get vaccines also engage in other healthy behaviors that affect their risk of dementia. However, researchers try to control for that “healthy user bias” in their studies, he adds. And the fact that multiple studies show similar results suggests there might be something special about vaccination.
Inflammation, experts suspect, could be that special something.
Inflammation and Dementia
Henry Ford Cognitive Health Services
Inflammation is the immune system’s response to an injury or infection. In the short term, an inflammatory response promotes healing. But over time, chronic inflammation can cause harm throughout the body, including in the brain.
“Inflammation is a stress on the body, and eventually on the brain,” Dr. Katramados says. “Any way we can decrease infections and inflammation will help us keep both body and brain healthy.”
When you’re sick with an infection like shingles, you experience inflammation. It’s possible that by helping people avoid illness, vaccines reduce the inflammation that could harm the brain. It’s also possible that vaccines are acting on the immune system more broadly—not only reducing infection, but somehow boosting immunity in a way that protects the brain.
Scientists are still sorting out exactly how vaccines might protect against dementia. However, Dr. Katramados says, “these findings reinforce the idea that brain health is deeply interconnected with immune health. Chronic inflammation appears increasingly important in neurodegeneration—the process that damages and destroys brain cells over time.”
Reducing Chronic Inflammation
Vaccines are just one way to reduce inflammation, Dr. Katramados adds. Other lifestyle choices and behaviors can also keep chronic inflammation at bay and reduce the risk of dementia.
Here’s what you can do:
- Eat a healthy diet
- Get enough sleep
- Treat sleep apnea
- Engage in regular exercise
- Control high blood pressure
- Don’t smoke tobacco or marijuana
- Maintain a healthy weight (and treat obesity)
What Shots Should Seniors Get?
Wondering if you should get vaccinated? Based on the evidence so far, Dr. Katramados wouldn’t recommend vaccines solely as a means to prevent dementia. But there are other good reasons to consider updating your shots.
Vaccines are a safe and powerful way to prevent serious diseases. “Vaccines remain important primarily because they prevent serious infectious diseases and their complications,” Dr. Katramados says.
Shingles, for example, causes a painful rash that can lead to persistent nerve pain called post-herpetic neuralgia. That pain can last for months or even years. The shingles vaccine is more than 90% effective at preventing shingles and post-herpetic neuralgia. The fact that it might also reduce the risk of dementia? Consider it an extra bonus.
The U.S. Centers for Disease Control and Prevention (CDC) recommends all adults over 50 get the following vaccinations:
- COVID-19
- Influenza (flu)
- Tdap
- Shingles
- Pneumococcus
- RSV (recommended for some adults over 50, but all adults over 75)
“At present, no vaccine should be viewed as a proven therapy to prevent dementia, but vaccination supports the broader principles of healthy aging,” Dr. Katramados says. “My recommendation is that patients follow evidence-based adult vaccination guidelines in consultation with their physicians.”
Reviewed by Angelos Katramados, M.D., a neurologist who sees patients at Henry Ford Hospital in Detroit.
