A double-blind, placebo-controlled, crossover pilot trial of low dose dimethylglycine in patients with autistic disorder.
Low-dose DMG did nothing for autism in a blinded trial, so skip it and demand the same proof for the next supplement.
01Research in Context
What this study did
Researchers gave eight boys with autism a low-dose DMG pill for a few weeks. Then they gave the boys a look-alike placebo for the same time.
No one knew which pill was which. The team used rating scales to track behavior in each period.
What they found
DMG did not beat the placebo on any scale. Scores bounced around, but the pill made no real difference.
How this fits with other research
Carey et al. (2002) ran the same double-blind setup with secretin and also saw zero benefit. Two null pills, two null results — the pattern strengthens the need for blinded tests.
Tonnsen et al. (2016) and Elder et al. (2006) tried gluten-free, casein-free diets under blind conditions. Again, no group-level gains. Together these studies show that popular autism supplements rarely pass a placebo check.
Hsieh et al. (2014) looked promising: an open-label pregnenolone trial reported small irritability drops. But without a placebo arm, those gains could be wishful thinking. The DMG paper reminds us to trust controlled data, not open labels.
Why it matters
Families often ask about DMG, secretin, or special diets. You can now say, “We have blinded trials showing no benefit.” Save them money and time. When the next miracle pill trends, insist on placebo proof before you sign on.
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02At a glance
03Original abstract
As the treatability of the syndrome of autism becomes more possible there is a great deal more interest in the effectiveness of various therapies. Although the very influential nonmedical literature cited in the Autism Research Review International Newsletter finds that dimethylglycine (DMG) is regarded as more effective than the usual psychopharmacologic drugs, there have been no studies of DMG using the currently accepted research methodology. We report a double-blind, placebo-controlled, crossover pilot study of low dose DMG and placebo in a sample of eight autistic males ranging in age from 4 years 5 months to 30 years 8 months, who completed the full 3 1/2-month study consisting of drug-free baseline periods at the beginning, end, and in-between two, 1-month double-blind trials in which DMG or placebo was given. Measures included the Campbell-NIMH rating scale, an experimental rating scale, and an individualized scale created for each child. Analysis of all three scales revealed no statistically significant differences, and parent reports were equally distributed. The major methodologic weaknesses of the study are thought to be the low dosage of DMG and the small sample size.
Journal of autism and developmental disorders, 1999 · doi:10.1023/a:1023023820671