But 0.2% of the children whose mothers did not take folic acid had autism, compared to 0.1% of the children of mothers who took the vitamin in pill form.
On Monday Allergan (nyse: AGN - news - people ) unveiled results showing that a pill derived from vitamin A might be nearly as effective as some of the biotech drugs.
Whether or not Clemens can demonstrate a vitamin B-12 deficiency, he is going to have to contend with questions about why chose injections of a vitamin that is found naturally in meat, fish and dairy products or in commercially-produced and readily-available pill form.