Young kids seem to have boundless energy. The colorings and preservatives in soft drinks, candy, and other foods can boost kids' activity levels higher still, a new study finds. This increase fosters hyperactivity and inattentiveness, potentially diminishing a child's ability to learn, the report's authors argue.
Each day for 7 weeks, nearly 300 youngsters in England—half around 3 years old, the rest around 8—received purple drinks. The drinks' color and taste never varied, but for 2 randomly assigned weeks, each child got drinks with a bonus: Either of two different mixes of food colorings, together with sodium benzoate, a general food preservative. Amounts of the additives were scaled to mirror what is found in a typical child's diet.