Fish Consumption Associated with Brain Shrinkage in Newborns

Physicians have known for many years that mercury in the human body is associated with neurological damage. Fish consumption is the main source of mercury in the human body.

Now a new video from my colleague Michael Greger, M.D.(see below) brings together several journal articles which specifically show how methylmercury in fish is damaging the human brain.

We have known for some time that there is a dose‚ a response relationship of prenatal mercury exposure and IQ. Dr. Greger’s video pointed out to me an article that appeared in the medical literature several years ago on the relation of mercury and newborn’s brains. This article specifically shows that there is a direct relationship between prenatal exposure to a low level of mercury in the mother, and the size of a newborn’s cerebellum.

Specifically in this article it was shown that “prenatal exposure to, what we consider to be, low levels of methylmercury does influence fetal brain development detected as decreased size of the newborn cerebellum.” The decreased size of the newborn cerebellum was up to 14% smaller in length.

What is the cerebellum and what does it do? First of all the cerebellum which is known as the “little brain” is the second largest part of the brain and is located near the base of the brain. Although the cerebellum accounts for only about 10% of the brain’s volume, it contains over 50% of the total number of neurons in the brain.


What is so important about this ? Traditionally the cerebellum has been considered a purely motor control device. However this is now appearing to not be true. Specifically as recently reported in Brain:The Journal of Neurology, researchers have found connections between the cerebellum and the hypothalamus in the brain. These pathways connect with neural circuits that govern intellect, emotion and autonomic function as well as sensorimotor control.

There is a condition called Cerebellar Cognitive and Affective Syndrome (CCAS). This condition occurs in adults and children with stroke or tumor involving the cerebellum. It is also seen in children born very preterm who have a small cerebellum.

The neurobehavioral deficits that occur in this condition can occur in the absence of a motor condition. They are characterized by “impairments in executive function, which includes planning, set shifting, verbal fluency, abstract reasoning, and working memory.” In addition, “impairment in spatial cognition and linguistic processing as well as a dysregulation of their affect” is seen in patients with this condition.

These latter symptoms sound very much like the symptoms that children with Autism Spectrum Disorder, and Attention Deficit Disorder (ADHD)have. We now have an epidemic in our country of neurodevelopmental disorders with an estimated one in five children growing up to have such a disorder. Could mercury be part of the cause?

Watch the video now!

So, given this new information on mercury and the fetus, my first question is how much fish, which is loaded with mercury, is good for a woman while she’s pregnant? The second question is how much mercury has been accumulated by the woman before she conceives which then comes out during pregnancy and affects the fetus and its brain?

The other interesting aspect of this research was the amount of mercury the researchers considered “high” in the mother. The so-called “high levels”, were approximately 1/3 of the level of mercury a woman would get if she ate one can of tuna per week. I find young women in my practice eating tuna sushi several times per week.

In the studies I quoted above, researchers used hair mercury, which is one indication of the body load of mercury. However we now know that not all women excrete mercury into their hair even if they have it in their body.

We realize that the best test for body burden of mercury, is a challenged urine, where a woman takes a medication that is known to be able to pull mercury out of her tissues and put it in the urine where it can be measured.

This is the exact protocol that environmental doctors have been using for so many years. And this in part is why I encourage women in my Preconception Pregnancy Planning Program to get as much mercury as possible out of their body before they conceive.

I encourage you to share this information with your friends and family who are of childbearing age. Encourage them to get off fish before and during pregnancy, and encourage them to find a doctor who can measure their body load of mercury and help clean it out, before they conceive. Nobody wants a child with a small cerebellum, now that we are realizing the importance of this major part of our brain.

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About Dr. Soram Khalsa

As an MD, Dr Soram specializes in Integrative Medicine combining diet, nutrition, acupuncture, herbs and nutrition. Visit Dr Soram’s Healthy Living Store where you’ll find high-quality nutritional supplements: