In July 2019 researchers from Sweden published the results of their study to assess the association of early nutrition on the later development of juvenile idiopathic arthritis. The researchers followed 15,740 children through childhood and adolescence to determine causes of various autoimmune medical conditions. Information on lifestyle and environmental factors was collected via questionnaires and a detailed diary kept during the first year of life to record nutritional data, including the date different foods were introduced. In addition, the children were monitored by biological samples taken at birth and then at the ages 1, 2.5, 5, 8, 10–12 and 13–16 years. During a period of 16 years, 59 children were diagnosed with juvenile idiopathic arthritis, although only 42 were available for this specific study. The cord blood of all 42 individuals with juvenile idiopathic arthritis was analysed for the presence of heavy metals, as well as the cord blood of 40 additional children, matched for age and sex, who acted as a control group. Results showed that fish consumption of at least once a week during pregnancy and during the first year of life was associated with an increased risk of juvenile idiopathic arthritis. Concentrations of aluminium, cadmium, mercury and lithium in cord blood were significantly higher in the group of children with juvenile idiopathic arthritis than in the control group. The frequency of fish consumption was seen to be directly associated with levels of cadmium, lithium and mercury, but not aluminium. Further research is required to explore whether even moderate exposure to aluminium, cadmium, mercury and lithium during pregnancy and early childhood may cause a negative effect on the immune system of the offspring.
Kindgren E et al. Heavy metals in fish and its association with autoimmunity in the development of juvenile idiopathic arthritis: a prospective birth cohort study. Pediatr Rheumatol Online J. 2019 Jul 2;17(1):33.