Bates, Michael N, Fawcett, Jackie, Garrett, Nick et al. · International journal of epidemiology · 2004 · DOI
This study looked at whether mercury in dental fillings causes health problems like chronic fatigue syndrome, multiple sclerosis, or Alzheimer's disease. Researchers tracked 20,000 New Zealand Defence Force members for about 20 years and compared how many dental fillings they received to whether they developed these illnesses. The study found no link between dental fillings and chronic fatigue syndrome, suggesting that amalgam fillings are unlikely to cause ME/CFS.
For ME/CFS patients, this large epidemiological study directly addresses a persistent concern about dental amalgam as a potential trigger or cause of chronic fatigue syndrome. The reassuring null finding (HR = 0.98) helps distinguish amalgam exposure from other investigated risk factors, contributing to evidence-based discussions about ME/CFS etiology.
This study does not prove that amalgam is completely safe universally, nor does it address potential mechanisms in individuals with specific genetic susceptibilities or mercury metabolism differences. It also cannot establish causation in either direction—the absence of association in this military cohort does not rule out amalgam effects in other populations or longer timeframes. Additionally, the study relies on diagnostic coding accuracy and may not capture subclinical disease or mild presentations of ME/CFS.
About the PEM badge: “PEM required” means post-exertional malaise was an explicit required diagnostic criterion for participant inclusion in this study — not that PEM was studied, observed, or discussed. Studies using criteria that do not require PEM (e.g. Fukuda, Oxford) are tagged “PEM not required”. How the atlas works →
Spotted an error in this entry? Report it →