A recent study published in Nature has found that older adults who received the shingles vaccine showed a significantly lower risk of developing dementia compared to those who did not. The research, conducted in Wales, analyzed data from approximately 283,000 individuals and revealed that vaccinated participants were 20% less likely to be diagnosed with dementia over a seven-year period.
The study took advantage of a unique policy in Wales where the shingles vaccine was offered to 79-year-olds but not to those aged 80 or older due to limited supplies. This created a natural experiment, allowing researchers to compare two otherwise similar groups—one that received the vaccine and one that did not. The findings were particularly pronounced among women, though the reasons for this gender difference remain unclear.
The shingles vaccine used in the study was the live-virus version (Zostavax), which has since been replaced in many countries, including the UK, by a newer protein-based vaccine (Shingrix). Both vaccines target the varicella-zoster virus, which causes shingles and is also linked to chickenpox. Previous research, including a 2023 study in Nature Medicine, has similarly suggested that shingles vaccination may help protect against dementia, though the exact mechanisms are still under investigation.
One leading theory is that viral infections like shingles may contribute to neuroinflammation, which could accelerate cognitive decline. By preventing shingles, the vaccine might indirectly reduce this risk. However, researchers caution that more evidence is needed to confirm a causal relationship.
Dr. Pascal Geldsetzer, the study’s senior author and an assistant professor at Stanford University, described the results as "striking," noting that the protective effect held up across multiple analyses. Meanwhile, Dr. Maxime Taquet of the University of Oxford, who led a related study in 2024, highlighted the potential for vaccines to open new avenues in dementia prevention, though he emphasized that much more research is needed.
Pharmaceutical company GSK, which produces Shingrix, is now conducting a larger study involving 1.4 million older adults in the UK to further explore the link between shingles vaccination and dementia risk.
While the findings are promising, experts stress that the primary reason to get vaccinated remains protection against shingles itself—a painful condition that can have serious complications, especially in older adults. The CDC and other health agencies already recommend the shingles vaccine for adults over 50 or 60, depending on the country.
For now, the study adds to growing interest in the potential role of vaccines and immune health in preventing dementia, a field that has seen few breakthroughs in recent decades. As research continues, the shingles vaccine could emerge as an unexpected tool in the fight against cognitive decline.
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