For decades, researchers have been trying to find a cure for dementia and age-related loss of memory and cognitive decline. Meanwhile, one potential aid may have been hiding in plain sight. A groundbreaking new study published in the journal Nature has just found that getting the shingles vaccine may reduce your risk of developing dementia by 20%.

A vaccination to prevent horribly painful shingles may offer an extra benefit: New research suggests it might lower the risk of dementia, too.

Several previous studies have suggested that shingles vaccinations might reduce dementia risk, but most could not exclude the possibility that people who get vaccinated might have other dementia-protective characteristics, like healthier lifestyles, better diets or more years of education.