Why do Autism behaviors improve with fever?

My little girl has a fever, 103 degrees F. I know fevers serve a purpose, our bodies are trying to kill the germ invaders that are making us sick. But I find myself reaching for medicine from time to time just to make her more comfortable and help her sleep. She’s a cranky mess and just wants to be held. And in my hours of holding her while she slept I got to thinking about something I hadn’t thought of in a while. A phenomenon I had heard about but hadn’t researched – that children with Autism often have improved behaviors when they have a fever. Have you ever noticed this? I asked my Aunt if this was true of her son, Lawrence. The response was one word – “always”. Since the topic is on my mind I wanted to do a little digging and figure out why this happens, see what the research has to say. I’ll break it down for you here, it’s absolutely fascinating.

The first study I found was published in 2017. The researchers gathered data from all the participants (demographic, behavioral and even genetic information) to see if there were any similarities between those that experience a “fever effect” and those that did not. Over 2,000 children participated in the study and of those, 17% noted behavioral improvements with fever. The children who experienced this “fever effect” also had lower non-verbal cognitive skills, less language and more repetitive behaviors than those who did not report behavioral improvements with fever. Very interesting. Another smaller study documented improved behaviors in 25 of the 30 child participants.

The final study I found was published just this year. Essentially what the researchers did was take mice in utero and expose the mother to an infection, which activated the mother’s immune system. This maternal immune activation causes social behavior deficits in the offspring and excessive neuron activity in a portion of the brain. Once born, if the offspring mice experience an inflammatory response, sociability is restored and the neuron activity is reduced. The researchers determined that sociability improved because the inflammation produced an immune system molecule, called interleukin-17a, which communicated with the brain, to directly impact neuronal activity and thus social behavior. Fascinating!

All of this to say that if you notice improved behavior when your child has a fever, you are not alone! Hopefully this sheds a little light on how common the fever effect is and gives us some clues as to why it may happen. So what can you do nutritionally if your child is sick?

  • Support with plenty of fluids and nutritious food. Light, mini meals are key here. Feeding a child with autism can be difficult under ordinary conditions, not to mention when the child is sick, but it can be done and there are ways to pack lots of nutrients into the foods your child likes!
  • Support with vitamins (work with a pro like me to help you figure out what vitamins your child needs to help fill the gaps in their diet and support their immune systems in times of sickness)
  • There is some research to suggest that Tylenol depletes glutathione, an antioxidant needed for detoxification. Additionally, those with autism may have sulfation issues and a reduced ability to detoxify acetaminophin (aka Tylenol), so it may be a good idea to discuss other options for pain killers or fever reducers with your doctor.


Well that’s all for now, better get to bed so I can rest up for tomorrow. Any questions, don’t hesitate to reach out here or on Instagram. All the best!


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