Vitamin supplements could help minimise symptoms of attention deficit hyperactivity disorder (ADHD), according to a New Zealand study.
Researchers from the University of Canterbury in Christchurch recruited 80 adults with ADHD and gave half supplements with a combination of vitamins D and B12, folate, magnesium, ferritin, iron, calcium, zinc and copper. The other half took a placebo.
After eight weeks, the people on the supplements all reported better attention span and had improvements in their hyperactivity and impulsivity, compared with the control group.
ADHD is a behavioural disorder that makes it hard for people to concentrate. They change rapidly from one thing to another without completing tasks, plus get restless and fidget.
ADHD affects as many as one in 20 adults, and is usually treated with medications that stimulate the central nervous system.
The researchers said taking vitamins wasn't more powerful than medication.
"Our study provides preliminary evidence of the effectiveness for micronutrients in the treatment of ADHD symptoms in adults," said study leader Professor Julia Rucklidge.
"This could open up treatment options for people with ADHD who may not tolerate medications, or do not respond to first-line treatments."
Philip Asherson, a professor in molecular psychiatry at London's Institute of Psychiatry in London, told the BBC that further investigation was needed.
"It's a good study, which is very interesting, but really needs replicating," he said.
"The mechanisms behind it remain unclear."
The research was published in the British Journal of Psychiatry.