Getting your flu shot could significantly lower your odds for a heart attack, according to researchers.
Vaccination against influenza is associated with a whopping 18 percent reduction in the odds of the cardiac event compared to people who were unvaccinated, a team from Hanghzou’s Zhejiang Chinese Medical University said last weekend.
The key lies in the vaccine’s ability to alleviate conditions related to heart attacks, the researchers theorized in a review of 15 observational studies that included more than 23 million adults.
The vaccine may help to reduce inflammation and a type of coronary artery disease that narrows the arteries, for example.
“While causal inference cannot be established, these findings support the potential role of influenza vaccination in cardiovascular risk prevention and highlight the need for further well-designed studies to clarify the nature and durability of this association,” the researchers wrote.
Still, “this meta-analysis indicates that influenza vaccination is associated with lower odds of myocardial infarction,” they said.
The researchers said future studies should be conducted to “clarify the underlying mechanisms and to refine the understanding of this association in contemporary populations.”
Not throwing away your shot
The findings come as data shows vaccination rates against respiratory illnesses have dropped in the U.S., with just 34 percent of American adults getting a flu shot by December 2025, according to a survey from the National Foundation for Infectious Diseases.
That marks a six percent reduction in flu shots since 2024, the foundation said.
While experts had initially warned that this year’s shot might not be as effective as those distributed in previous flu seasons, researchers at the University of Pennsylvania said last month that the vaccine may be more effective than previously believed and protect against the most severe effects of infection.
Still, approximately 134 million doses of flu vaccine have been distributed in the U.S. this season, according to data from the Centers for Disease Control and Prevention.
A historic season
This season has been one of the worst for flu in years, resulting in 22 million illnesses, 280,000 hospitalizations and 12,000 deaths.
Child deaths have also started to pick up months into the season, rising to a total of 60 after eight more were reported last week.
“Among children who were eligible for influenza vaccination and with known vaccination status, approximately 90 percent of reported pediatric deaths this season have occurred in children who were not fully vaccinated against influenza,” the CDC said.
Flu infections are more severe in young children, seniors and people with chronic health conditions.
Common side effects of infections include a fever, cough, sore throat, headache, fatigue, muscle or body aches and a runny or stuffy nose.
Supporting data
Heart attacks are a more serious complication of flu, but tend to be more common during flu season.
Previous research shows that people are six times more likely to have a heart attack in the week after diagnosis, and another study found nearly one in eight adult patients hospitalized with flu over flu seasons had an acute cardiac event.
The CDC said there has long been evidence that vaccination against flu can help prevent cardiovascular events.
“Flu vaccination has long been associated with lower rates of some cardiac events among people with heart disease, especially among those who have had a cardiac event in the past year. And that’s supported by data from the latest randomized clinical trials,” the agency wrote.
“A meta-analysis published in November 2023 of studies involving more than 9,000 patients reported a 26 percent decreased risk of heart attacks in people who received a flu vaccine and a 33 percent reduction in cardiovascular deaths.”
