Objectives: Autism rates in the United States are increasing at a rate of 15% per year. Autistic children are diagnosed by age 3 when they have problems communicating and interacting socially. This study uses nutritional epidemiology and an ecologic study design to link the possible cause of autism to nutrition by creating autism rates for the 50 states of America and comparing them with published measures of infant nutrition such as duration of exclusive breast-feeding and participation in the Women, Infants, and Children (WIC) program. The percentage of infants with measles, mumps, and rubella (MMR) inoculations was also compared with the autism rates. Study
Design: Autism rates for each state were established. The percentage of infants who participate in the WIC program for low-income families was calculated for each of the 50 states as well as 21 New Jersey and 30 Oregon counties and compared with their autism rates. An ecologic study design with correlation coefficients is limited, but it is useful for generating hypotheses to be tested.
Results: The states with the highest WIC participation have significantly lower autism rates (p < 0.02). A similar pattern was observed in 21 New Jersey counties (p < 0.02) and 30 Oregon counties (p < 0.05). In contrast, there was a direct correlation with the increasing percentage of women exclusively breast-feeding from 2000-2004 (p < 0.001). Infants who were solely breast-fed had diets that contained less thiamine, riboflavin, and vitamin D than the minimal daily requirements (MDR). There was no correlation of MMR inoculations with the autism rate.
Conclusion: The mothers who are exclusively breast-feeding should also continue their prenatal vitamins or their equivalent and make better dietary choices. These results suggest that autism may be nutritionally related to a possible deficiency of riboflavin or the cognitive vitamins such as thiamine or vitamin D. However, due to an ecologic study design there is a potential for fallacy because individuals were not examined. The results suggest the need for a robust observational study in advance of, and to confirm the need for, an intervention study.