Strokes are serious medical emergencies that happen when blood flow to the brain is suddenly blocked, much like a road being closed off with no warning. This disruption can cause lasting brain damage and even be life-threatening.
The most common kind of stroke is called an ischemic stroke. It occurs when a blood vessel leading to the brain becomes blocked, often due to a clot. Since strokes are one of the top causes of death and disability worldwide, researchers are always looking for new ways to reduce their risk.
One surprising area of interest in recent years has been the flu vaccine. Most people know the flu shot as a yearly jab that helps prevent influenza, especially during the colder months. But some scientists have wondered whether it might do more than just stop the flu. Could it also lower the risk of stroke?
Dr. Francisco J. de Abajo and his team in Spain decided to explore this idea. They were inspired by earlier studies suggesting that getting the flu could raise the risk of having a stroke. So they asked: If catching the flu makes strokes more likely, could getting vaccinated against the flu help protect people?
To find out, the researchers looked at medical records collected over 14 years. They focused on more than 14,000 people who had suffered a stroke and compared them to over 71,000 people of similar age and gender who had not had a stroke. They then checked who had received a flu shot at least two weeks before their stroke or the matching date in the control group.
At first, the numbers didn’t look very different. About 41% of the people who had strokes had received the flu vaccine, compared to just over 40% in the group without strokes. This seemed like only a small difference.
However, the researchers noticed something important—people who got the flu shot were generally older and more likely to have other health conditions like high blood pressure or high cholesterol, both of which are known to raise stroke risk.
When the researchers adjusted the data to take these factors into account, the results became more meaningful. They found that people who had received the flu shot were about 12% less likely to have a stroke than those who hadn’t been vaccinated.
This suggests that getting a flu vaccine might provide some protection against stroke, especially for people who are already at higher risk.
Interestingly, the same study looked at whether getting the pneumonia vaccine had a similar effect, but it didn’t find any clear connection. Only the flu vaccine seemed to have a link to lower stroke risk.
Dr. de Abajo explained that these results give people yet another reason to get their yearly flu shot. While the flu vaccine is mainly meant to protect against influenza, it might also reduce the chances of having a stroke—an unexpected but valuable bonus.
Still, the researchers caution that this was an observational study. That means it showed a link between flu shots and fewer strokes, but it didn’t prove the vaccine directly caused the lower risk. Other factors not included in the study might have played a role. For example, people who get vaccinated regularly may also take better care of their health in other ways.
Even with those uncertainties, the study adds to growing research suggesting that vaccines can have wider benefits beyond just preventing infections. It encourages more research into how flu shots might protect the heart and brain as well.
For people who want to further lower their stroke risk, other steps like eating a healthy diet (such as the MIND diet), drinking tea or coffee in moderation, and getting enough antioxidants from fruits and vegetables can also help.
But this study, published in the journal Neurology, gives one more reason to roll up your sleeve for that flu shot each year—not just to avoid the flu, but possibly to protect your brain as well.
If you care about stroke, please read studies that diets high in flavonoids could help reduce stroke risk, and MIND diet could slow down cognitive decline after stroke.
For more health information, please see recent studies about antioxidants that could help reduce the risk of dementia, and tea and coffee may help lower your risk of stroke, dementia.
Copyright © 2025 Knowridge Science Report. All rights reserved.
