Is there a link between zinc and autism?


Over the last few years different studies have indicated there may be a link between Zinc and autism. Zinc is known to perform a number of important functions in the cell and body – including building proteins and DNA.  While there is a link it has been tough to establish whether Zinc deficiency actually causes autism or whether there is just an association. Now a new study published in Frontiers in Molecular Neuroscience suggests that a zinc deficiency in early childhood may contribute to autism – strengthening the link between the two.


Autism causes difficulties in communication and social interaction. Common symptoms include repetitive actions, reduced eye contact, and trouble recognizing emotions in others. It is fairly common with 1 in 59 children having it and is more common in boys than girls. It is usually diagnosed in the first 3 years of life. To this day researchers are working hard to understand what causes autism to develop.


Many believe the basis for this group of diseases is genetic with the environment providing an important contributing factor as well. Particularly some recent research has focused on autism and synapse formation. Synapses are the communication points between neurons (the cells in our brain). Dr. Sally Kim of Stanford University School of Medicine in California whose research focuses on this, explains: “Autism is associated with specific variants of genes involved in the formation, maturation, and stabilization of synapses during early development. Our findings link zinc levels in neurons — via interactions with the proteins encoded by these genes — to the development of autism.”


The researchers showed that zinc can help speed up the maturation of some of these receptors and aide in the correct formation of synapses. According to co-senior author, Professor John Huguenard “This suggests that a lack of zinc during early development might contribute to autism through impaired synaptic maturation and neuronal circuit formation.”


The big question still remains to be answered – will zinc supplements reduce autism risk?


The quick and dirty – we still do not know!


Professor Craig Garner, of the German Center for Neurodegenerative Diseases in Berlin, spelled it out: “Currently, there are no controlled studies of autism risk with zinc supplementation in pregnant women or babies, so the jury is still out.” Basically – there are no studies yet that compare pregnant women getting zinc supplementation vs those that don’t.


Zinc is an essential mineral (meaning humans can’t survive without it). It is naturally present in some foods, available as a dietary supplement, and also found in many cold lozenges and some over-the-counter drugs sold as cold remedies. It’s involved in a ton of processes including a role in immune function, protein synthesis, wound healing, DNA synthesis, normal growth and development during pregnancy, childhood, and adolescence. It is also required for proper sense of taste and smell. It is important to have a daily intake of zinc also because the body has no specialized zinc storage system. Foods that are high in zinc include oysters (which contain more zinc per serving than any other food), red meat, poultry, beans, nuts, crab, lobster, whole grains, fortified breakfast cereals, and dairy products.

While Zinc deficiency is rare in North America the people most at risk are people with gastrointestinal disease (such as Ulcerative colitis or Crohn’s disease), vegetarians, alcoholics, pregnant women and babies that are exclusively breastfed.


However, before you start taking zinc by the spoonful it’s important to know that too much zinc can also be harmful. Too much can prevent the body from absorbing copper, leading to anemia (low blood levels) and weak bones. It is important to note that a zinc deficiency does not necessarily mean that a person is consuming too little of the mineral. There may be other explanations – for example the gut may not be absorbing the nutrient correctly.


In conclusion there is still much to learn about autism and what causes it. Exploring the interaction between zinc and development of neurons could hold promise for future treatments and, possibly, the prevention of this disease.