Vitamin C and Autism Print E-mail

Written by Lara Pullen, PhD

ImageWhat is it?
Vitamin C (ascorbic acid) is an essential water-soluble vitamin that is found naturally in many foods. Vitamin C is important for many biological processes, including the production of neurotransmitters. Vitamin C also acts as an anti-oxidant, protecting the body against damage from free radicals.

What’s it like?
Vitamin C is found naturally in many foods, particularly citrus fruits such as oranges, tangerines, and grapefruits. Vitamin C can be purchased over-the-counter, online, or at grocery, drug, or health-food stores. It can be taken every day. Unfortunately, it is not clear what the proper dose for children with autism should be. If you choose vitamin C as an alternative therapy, ask your child’s pediatrician what dose is appropriate for your child.

What is the theory behind it?
Some children with autism may have a vitamin C deficiency. One study demonstrated normal vitamin C levels among children with autism , while another reported low levels. Some investigators believe, however, that supplementation with vitamin C can be helpful even for children with normal levels of vitamin C.

Vitamin C has been shown to have a calming effect on behavior in humans. In animals, stereotyped behavior, one of the characteristics of autism, was reduced by treatment with vitamin C. Scientists hypothesize that vitamin C has these effects because it affects the brain signaling system called the glutamatergic system and/or the brain’s response to an important neurotransmitter called dopamine.

Another explanation for the effectiveness of vitamin C is its anti-oxidant properties. Some researchers have theorized that children with autism may have more trouble managing free radicals than other children do. Free radicals are naturally-occurring chemicals that play important roles in normal functions in the body, but also can cause damage in the brain, immune system, and other tissues or organs in the body. The body has systems to protect tissues from free radical damage, and anti-oxidants are important for this protection. Because it is an anti-oxidant, vitamin C can protect the body against the damaging effects of free radicals.

Does it work?
So far, only one controlled study has shown that vitamin C can help treat behavioral problems associated with autism. This double-blind experiment showed that high doses of vitamin C in children with autism had significant positive effects on behavior, compared against their own behavior scores when they were taking a placebo. However, this study was very small (only 18 children), and has not been replicated.

Another research report showed that high doses of vitamin C may help sleep and gastrointestinal problems in children with autism. In this study, vitamin C was taken along with other vitamins, so it’s not clear which vitamin was responsible for the positive outcomes.

Is it harmful?
For most people, vitamin C is thought to be harmless. However, tolerance for vitamin C can vary. Therefore, you should watch your child carefully for signs of an upset stomach or diarrhea. The U.S. FDA Recommended Daily Intakes are 15-75 mg/day for children, and 75-90 mg/day for adults. Check with your child’s pediatrician before starting treatment.

Cost
The cost of vitamin C treatment depends on the dosage selected. A bottle of 100 tablets at 1000 mg (1 g) can cost anywhere from $5-20, depending on the quality of the ingredients and the store. The study showing positive effects on behavior used vitamin C donated from a pharmaceutical supply company (Hoffman-LaRoche). Vitamin C supplements may contain sodium, calcium, magnesium, potassium, or zinc ascorbates (salts) of ascorbic acid; ask your child’s pediatrician which form is best for your child. Vitamin C supplements can also be found online, sometimes at a discount.


Resources
Healing Thresholds: Connecting Community and Science to Heal Autism


Author
Lara Pullen is the CEO of Healing Thresholds (www.healingthresholds.com), a website dedicated to the communication of the science of therapies for autism. She is also the president and founder of Environmental Health Consulting, Chicago, IL, where she manages a team of writers and scientists to produce a comprehensive literature review of childhood exposure to environmental contaminants, and provides expert consultations on human health risks from environmental contaminants. Lara Pullen holds a doctoral degree in microbiology and immunology earned at the Northwestern University Medical School in Chicago, Illinois. She is a freelance medical writer for various clients in the U.S. and Canada and has written on a wide range of topics from Alzheimer's disease to diabetes. She is the mother of three children, the youngest of whom has Prader-Willi Syndrome.




 

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Despicable Me ~ 4 stars

Cats & Dogs: The Revenge of Kitty Galore ~ 2 stars

Toy Story 3 ~ 4 stars

On DVD:
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Furry Vengeance ~ 1 star

Diary of a Wimpy Kid ~ 3 stars

Clash of the Titans ~ 2 stars