THURSDAY, May 7, 2026 (HealthDay News) -- No causal association appears to exist between aluminum-adjuvanted vaccines and serious or long-term health outcomes, according to research published online May 6 in The BMJ.Pamela Doyon-Plourde, from the Public Health Agency of Canada in Ottawa, and colleagues conducted a systematic review of human evidence on potential health effects of aluminum-adjuvanted vaccines. Fifty-nine studies were included in the review: 37 case series, 11 randomized controlled trials, nine cohort studies, and two ecological studies.The researchers consistently found no association between aluminum-adjuvanted vaccines and serious or long-term health outcomes, including asthma, autism spectrum disorder, or other chronic conditions, based on high-quality evidence from randomized controlled trials and large cohorts. With respect to macrophagic myofasciitis, studies were generally small and methodologically limited, with no credible evidence of a causal association. After diphtheria-tetanus-pertussis vaccines, localized persistent nodules or granulomas were observed infrequently, consistent with delayed type hypersensitivity. High-certainty randomized controlled trials revealed no consistent increase in risk with aluminum-adjuvanted formulations for common adverse events such as headache and myalgia. When observed, differences were small and mainly mild to moderate in severity. The studies were often methodologically limited, with serious or critical risk for bias for most case series and ecological studies."These findings are consistent with the broader postlicensure safety evidence base, which supports continued use of aluminum-adjuvanted vaccines in immunization programs," the authors write.Abstract/Full Text.Sign up for our weekly HealthDay newsletter