Vitamin B6 and Magnesium for treating autism

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Contents 1 History 2 Intervention 3 Reported Outcomes 4 Limitations 5 References

[edit] History

Vitamin B6 (pyridoxine) and magnesium are often thought to be useful for improving outcomes for children with autism. The origin of this treatment is Linus Pauling’s orthomolecular theory of psychiatry, “the treatment of mental disease by the provision of optimum concentrations of substances normally present in the human body” (Pfeiffer, Norton, Nelson, & Shott, 1995). Vitamin B6 is used to promote the development of dopamine and serotonin, which are often thought to be lacking in children with autism (Pfeiffer et al. 1995, Healing Thresholds). Research has also found lower levels of homovanillic acid (HVA) in children with autism. HVA is a metabolite of dopamine so lower levels of HVA suggest lower dopamine levels. The administration of vitamin B6 increases HVA levels in blood and urine (Pfeiffer et al., 1995). Magnesium is also thought to be deficient in children with autism. Magnesium is present in many green vegetables but children with autism do not have enough magnesium in their blood and often need supplemental magnesium (Healing Thresholds). Magnesium has been found to have a calming effect on children with Attention Deficit Hyperactivity Disorder (ADHD).

[edit] Intervention

Most of the studies that have investigated this treatment used 30 mg/kg of vitamin B6. This dosage was used because the maximum daily dose of vitamin B6 should not exceed 1 gram (McLaughlin & Brown, 1995, Healing Thresholds). In combination with the 30 mg/kg of B6 is a 10-20 mg/kg dose of magnesium, although most studies used between 10 and 15 mg/kg of magnesium (Pfeiffer, Norton, Nelson, & Shott, 1995). Vitamin B6 and magnesium are combined to eliminate the negative side effects of B6 administration. High dosages, over 2 grams/day, of B6 can cause nerve damage in adults. B6 also has a bitter taste that can be aversive to children. However, there are a few studies that administered vitamin B6 alone to children with autism and found no negative side effects (Healing Thresholds).

[edit] Reported Outcomes

Pfeiffer, Norton, Nelson, and Shott (1995) summarized the outcomes of 12 studies completed between 1975 and 1995. Many studies report behavioral and laboratory results for participants. Ten of the 12 studies reported an improvement in behavior, although improvements were typically only seen in 1/3 to ½ of the participants. All of the studies found a relative improvement in measures related to dopamine levels, which is thought to be related to improving behavior in children with autism.
In contrast, Findling, Maxwell, Scotese-Wojtila, Huang, Yamashita, & Wiznitzer (1997) found no improvements in children with autism after treatment with vitamin B6 and magnesium. Findling et al. (1997) examined the safety risks of this treatment and did not find an increase in toxicity in the children in the treatment group, which suggests that the treatment is not harmful. There were no significant differences between the treatment group and the placebo group on several behavioral measures. Hyperactivity and impulsivity factors were analyzed.

[edit] Limitations

A group of 4 researchers were all involved in the majority, ranging from 6-11, of the studies included in Pfeiffer et al.’s (1995) summary of the literature on the use of mega-vitamins for treating children with autism. Several of these studies may have included the same participants. The small number of authors and participants suggest a possible confounding of results and a potential bias among the researchers. The only independent study, Findling et al. (1997), is also the only study to report a negative result for the treatment. More independent studies need to be conducted.
The sample size used in many of the studies was too small to allow for accurate statistical analysis of the data. Small sample sizes may have led to exaggerated results or inaccurate portrayal of effect sizes. Small sample sizes may also have produced limited results since not all participants respond to this treatment (Rimland, 1998).
Post- intervention data were frequently taken within 2 weeks of treatment completion, which may not have allowed for the B6 and magnesium to wash out of the child’s body (Rimland, 1998). This may have suggested that treatment effects continued after treatment was stopped.
Researcher bias may also have affected results. Rimland (1998) has written several rebuttals to studies but the rebuttals are frequently based on limitations already described in the studies. The small number of researchers and the limited literature does not allow for an unbiased analysis of the findings. It has also been suggested that studies were designed to produce a pre-determined effect and were not accurate examinations of the treatment.
Overall, the effectiveness of this treatment has not been firmly established. It does show positive results in some participants, although it appears to only be effective in ½ of the participants at best. The results of many studies may also not be accurate due to researcher bias and methodological shortcomings. More research is needed before the effectiveness of this intervention can accurately be evaluated.

[edit] References

Findling, R. L., Maxwell, K., Scotese-Wojtila, L., Huang, J., Yamashita, T., & Wiznitzer, M. (1997). High-dose pyridoxine and magnesium administration in children with autistic disorder: An absence of salutary effects in a double-blind, placebo-controlled study. Journal of Autism and Developmental Disorders, 27, 467-478.
Pfeiffer, S.I., Norton, J., Nelson, L., and Shott, S. (1995). Efficacy of vitamin B6 and magnesium in the treatment of autism: a methodological review and summary of outcomes. Journal of Autism and Developmental Disorders, 25(5), 481-493.
Rimland, B. (1998). Critique of “Efficacy of vitamin B6 and magnesium in the treatment of autism.” Journal of Autism and Developmental Disorders, 28(6), 580.
Rimland, B. (1998). High dosage vitamin B6 and magnesium in treating autism: response to study by Findling et al.. Journal of Autism and Developmental Disorders, 28(6), 581-582.
Healing Thresholds. Retrieved May 27, 2008 from http://autism.healingthresholds.com/therapy/vitamin-b6-and-magnesium.