Nearly two-fifths of the U.S population may be deficient in Vitamin B12, according to a recent study. Researchers involved in the ongoing Framingham (Massachusetts) Offspring Study found that 39 per cent of volunteers have plasma B12 levels in the "low normal" range - below 258 picomoles per litre (pmol/L). Although well above the currently accepted deficiency level of 148 pmol/L, some people exhibited neurological symptoms at the upper level of the deficiency range. Nearly 9 per cent of the 3,000 study population fell below the current deficiency level. And more than 16 per cent fell below 185 pmol/L. Scientists found that people eating more fortified cereals and dairy products could improve their B12 status to almost the same degree as taking supplements containing the vitamin. Results of the study were published in the August 2000 issue of Agricultural Research magazine.