News in brief - Aug. 4, 2003

Accelerated head growth might suggest autism - Vitamins as cancer prevention questioned

Accelerated head growth might suggest autism

A recent study suggesting that abnormally fast head growth can indicate an infant's risk for autism might help physicians better diagnose the disorder.

Increased head growth might mean the brain is making bad connections that will contribute to impaired function, researchers from the University of California at San Diego said in the study, published in the July 16 Journal of the American Medical Association. Researchers used data about birth measurements of 2- to 5-year-old children who were diagnosed with autism spectrum disorder. Although infants with autism often have smaller heads at birth, the study found that they had faster head growth in the first year of life, with heads 84% larger than other healthy infants. In the study, about 59% of infants with autism showed accelerated head growth, compared with 6% of non-affected infants.

Vitamins as cancer prevention questioned

The U.S. Preventive Services Task Force found insufficient scientific evidence to recommend vitamin supplements as a way to prevent cancer or heart disease and recommended against the use of betacarotene supplements in smokers because of a possible increased risk of lung cancer and death.

The task force's conclusions are based on a review of studies on the use of vitamins A, C or E, multivitamins with folic acid or antioxidant combinations to reduce the risk of cancer or cardiovascular disease in adults.

The findings are published in the July 1 Annals of Internal Medicine.

Although most studies reviewed by the task force showed that taking vitamins according to recommended daily allowances does not cause harm, several adverse effects can be caused by taking moderate or excessive doses of certain vitamins. For example, moderate doses of vitamin A may reduce bone mineral density, and high doses may cause liver damage or, in pregnant women, damage to a fetus.