According to a new study published in the Journal of the American Medical Association, women who consume fish during pregnancy have a higher likelihood of having children with autism.

Researchers from the University of Southern California surveyed mothers and children in Southern California to find out how much fish they ate during pregnancy. The results showed that those who ate a lot of fish were more likely to have autistic children. The association was highest for the consumption of shellfish and large fish such as swordfish and shark.

What is Autism?

Autism, or autism spectrum disorder (ASD), is a developmental disorder that affects communication and behavior. Autism affects an estimated 1% of the population globally, with higher rates among boys than girls.

The exact cause of autism is still unknown, but it is believed to be a combination of genetic and environmental factors.

What is in Fish?

Fish is a high protein food that is low in saturated fat and a good source of omega-3 fatty acids, vitamins D and B2, calcium, phosphorus, and minerals such as iron, zinc, iodine, magnesium, and potassium.

However, some types of fish can contain high levels of mercury due to pollution in the oceans. Mercury is a neurotoxin that can affect the nervous system, brain, and other organs in both adults and children. Fish that are high in mercury include swordfish, shark, king mackerel, and tilefish.

How Much Fish Should Pregnant Women Eat?

The Dietary Guidelines for Americans recommend that pregnant women eat at least 8-12 ounces (2-3 servings) of a variety of fish each week. However, they should avoid fish that are high in mercury.

Pregnant women should also avoid raw or undercooked fish, as well as smoked or refrigerated fish unless it is reheated until steaming hot. They should also avoid fish that are high in environmental contaminants such as polychlorinated biphenyls (PCBs), dioxins, and pesticides.

What did the Study Find?

The study, conducted by researchers from the University of Southern California, analyzed data from a cohort of 1,105 mother-child pairs in the Southern California Children’s Environmental Health Study.

The mothers were surveyed about their fish consumption during pregnancy, and the children were evaluated for autism using the Social Communication Questionnaire (SCQ) and the Autism Diagnostic Observation Schedule (ADOS).

The results showed that the children of the mothers who ate the most fish during pregnancy had a 42% higher risk of autism compared to the children of the mothers who ate the least fish.

The association was stronger for autism with intellectual disability (ID) than for autism without ID. The association was also stronger for fish with high mercury levels, such as swordfish and shark, than for fish with lower mercury levels.

What are the Implications of the Study?

The study suggests that high levels of mercury, rather than omega-3 fatty acids or other nutrients in fish, may be responsible for the association between fish consumption during pregnancy and autism.

Mercury is known to cross the placenta and affect the developing fetal brain. However, the study does not prove causality, and other factors may be involved.

The study has important implications for pregnant women, as well as public health policies. Pregnant women should be informed about the potential risks of fish consumption during pregnancy, especially high-mercury fish.

Public health policies should also consider the potential risks of mercury exposure and the promotion of low-mercury fish consumption.

Conclusion

The study suggests that consuming fish during pregnancy is associated with a higher incidence of autism, especially for mothers who consume fish with high mercury levels.

Pregnant women should be aware of the potential risks of fish consumption during pregnancy and avoid high-mercury fish. Public health policies should also consider the potential risks of mercury exposure and promote low-mercury fish consumption.