AUTISM RATES ASSOCIATED WITH NUTRITION AND THE WIC PROGRAM

Emma Frandsen

Nutrition 190

BACKGROUND INFORMATION

Autism or autism spectrum disorder (ASD) is the term for a group of complex disorders of brain development

ASD includes autism, Asperger disorder, and pervasive developmental disorder

Characterized by: difficulties in social interaction, verbal and nonverbal communication and repetitive behaviors 

BACKGROUND INFORMATION

No confirmed cause of autism

Undiagnosed until age 3 Increasing at a rate of

14-20% per year in the US and Canada

The same diagnostic techniques have been used for 20 years; increase due to environmental factors

STUDY PURPOSE AND HYPOTHESIS

Purpose: compare the rates of autism for the 50 States of America with the published measures of infant nutrition (duration of exclusive breastfeeding, WIC program participation, etc.) to link the possible cause of autism to nutrition

Hypothesis: Better nutrition practices (WHO recommendations) during infant feeding and development associated with lower rates of autism

METHOD: ECOLOGICAL STUDY DESIGN

Ecological study: study that averages the impact of risk-modifying factors on health outcomes for populations defined either geographically or temporally

Population: 50 states Risk-modifying factors: possible

environmental/nutritional causes of autism (thiamine, vitamin D, MMR shot)

METHODS AND DATA: AUTISM RATES

For comparison among states, rates needed to be established

2000 US census; number of autism cases divided by the number of individuals age 3-21 living in a particular state at the time of the 2000

AUTISM RATES COMPARED WITH…

Per capita income WIC program participation percentage Percentage of breastfeeding Solar irradiation (vitamin D exposure) Average of children receiving their measles,

mumps, and rubella (MMR) shots from 2001-2004

DATA: WIC PROGRAM AND BREASTFEEDING

WIC program participation listed by state by the US Department of Agriculture

Program helps women make nutritious choices; breastfeeding women can stay in program longer than non-breastfeeding mothers

CDC lists breastfeeding by state; categorized into 1)ever breastfeeding 2) 6 mo exclusive 3) 12 mo exclusive

RESULTS

Per-capita income correlated to autism (r=-0.54 p<0.001)

Greater income = ability to afford more nutritious food and health care

WIC children considerably less likely to have autism than non-WIC children

CASES OF AUTISM VS.WIC PARTICIPATION

The autism rate from 2000–2003 and the percentage of WIC participation in 50 states in 2004. The correlation is −0.37 with a probability of <0.02.

EXCLUSIVE BREASTFEEDING AND AUTISM

Positive correlation found between 6 months exclusive breastfeeding and the autism rates for 2000-2003

Infants exclusively breastfed for 1 year also had higher correlation

No significant correlation for 3 months exclusive breastfeeding

THE TOTAL AUTISM CASES AND THE AVERAGE PERCENTAGE OF EXCLUSIVE 6-MONTH BREAST-FEEDING IN THE UNITED STATES FROM 2000–2004

BREAST MILK VS. COWS’ MILK

Ecological link of breastfeeding to autism observed

Compared levels of thiamine, riboflavin, and vitamin D in breast milk with cows’ milk (derived from National Dairy Council)

Breast milk had markedly lower amounts of the 3 vitamins

Different study (Lonsdale and Shamberger) found an improvement in older autistic children treated with a thiamine derivative

DISCUSSION

Results show ecological statistical links between autism and infant nutrition

WIC provides low-income mothers with important vitamin source for infants

Breast milk in combination with nutritious food lowers autism risk

DISCUSSION

Correlation between solar energy exposure and autism not significant; study concluded vitamin D not a factor in autism

No correlation between MMR shots and autism rates

DISCUSSION

Longer the duration of exclusive breastfeeding, the greater the correlation with autism

A lack of thiamine or riboflavin could result in autism

Mothers who breastfeed should take prenatal vitamins and eat a diet high in B-vitamin-rich food

STUDY LIMITATIONS

Little control in an ecological study design Does not account for many other possible

variables Future observational or interventional study

to confirm link between thiamine or riboflavin deficiency and autism