Higher Mercury Level From Eating Fish May Heighten Risk of ADHD in Unborn Babies

Consuming omega 3’s during pregnancy is important for your baby’s health. Not only is it good for your baby’s eyes, but it also helps boost their brain development.  As the main source of Omega 3’s, fish often comes under fire due to its high Mercury content.  The is especially true for larger fishes that have been the water longer and have had more time to absorb the toxic compound.

A new study suggests that mother’s intake of fish during pregnancy may affect the chances of her baby developing Attention Deficit Hyperactivity Disorder (ADHD) later in life. This was mainly due to the higher level of mercury which came from eating bigger fishes. While it is not new that pregnant women should limit their fish intake, the suggestion that this could lead to their child developing ADHD is a fact that will surprise many.

Researchers from the Boston University School of Public Health in Massachusetts found that those who ate at least two servings of fish per week had about 60 percent lower risk of kids developing certain ADHD-like symptoms. But when the fish intake containing mercury was higher, it caused an increase in mercury levels leading to higher chances of developing symptoms like hyperactivity, inattentiveness and impulsiveness.

One in ten children in the United States is affected by ADHD and while the researchers cannot directly link the cause and effect of fish intake and ADHD, the study shows a correlation between the two.

“The really important message is to eat fish. Just stay away from mercury containing fish, because these protective effects are pretty important,” said Sharon Sagiv, the study’s lead author.

She adds that it is best to stay away from big fish like swordfish and tuna that contain higher amounts of mercury. She advises to choose smaller fish varieties like haddock and salmon instead.

For the research they followed 788 children who were born near New Bedford, Massachusetts, between 1993 and 1998. They analyzed hair samples of the mothers taken right after delivery and also looked at the food diary of the mothers to determine their fish intake.

When these children were 8 years old, the researchers asked their teachers to analyze their behavior and check if they ‘exhibited ADHD-like symptoms’.

After compiling the results researchers found that in those moms with 1 micrograms of mercury per gram in their hair there was a 60 percent increase in the risk of their child exhibiting ADHD-like behaviors.

This finding contradict the U.S. government’s recommendation that says pregnant women should eat no more than two six-ounce servings of fish per week to limit their exposure to mercury.

“I think it does call into question those guidelines, but this is only one study and the results should be confirmed,” Sagiv said.

Dr. Bruce P. Lanphear who wrote the editorial accompanying the study agrees that expectant mothers should avoid eating big fishes but he also adds that a long term solution is needed.

“In the long term we have to really find ways to fight contamination levels in fish so years from now we don’t have to give this advice,” he said.

Omega 3’s can also be found in non-fish products such as Flaxseed, Hempseed, walnuts, Tofu, Romaine Lettuce, Brussel Sprouts and Summer Squash.



About the author


Atula is a writer, traveler and a nature-lover. She is also mom to a boy who seems to have inherited all her creative genes. When Atula is not busy making up stories with her son, she writes for numerous magazines, websites and blogs. She is also working on her site on endangered species called

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