Fish oil supplements might help ADHD children, but only those with omega-3 deficiency, says study
Children who don't get enough omega-3 from fish, nuts and spinach and have Attention deficit hyperactivity disorder (ADHD) may stand to benefit from omega-3 fish oil supplements, finds a new study.
But the supplements hurt children with normal levels of omega-3 in their blood: their symptoms worsened, especially impulsivity, according to results from the study. "The omega-3 supplements only worked in children that had lower levels of EPA [omega-3] in their blood, as if the intervention was replenishing a lack of this important nutrient. For those children with omega-3 deficiency, fish oil supplements could be a preferable option to standard treatments," says Professor Carmine Pariante, senior researcher from the Institute of Psychiatry, Psychology & Neuroscience at King's College London.
"It is possible that EPA [omega-3] deficiency is more common among children with ADHD in countries with less fish consumption, such as in North America and many countries in Europe, and that fish oil supplementation could therefore have more widespread benefits for treating the condition than in our study," says Professor Kuan-Pin Su, co-lead researcher from China Medical University in Taichung, Taiwan.
Children with ADHD show inattention, hyperactivity and impulsivity. The CDC estimates that 6.1 million children were diagnosed with ADHD in 2016.
"Drugs to treat the condition work well for 60-80% of children who take them. But that leaves 20-40% of children who have a poor response to the drugs or who suffer from side-effects," wrote Dr. Jane Chang, Visiting Researcher, Child and Adolescent Psychiatry, King's College London.
It is for these children that omega-3 supplements may offer hope. But so far, studies evaluating the efficacy of the supplement have shown contrasting results: some children get better, others get worse. The mixed results mean that the US Food and Drug Administration (FDA) has not approved the supplement.
The conflicting results, according to the authors, may be due to the fact that omega-3 fatty acids were given to ADHD children without checking if they had a deficiency of omega-3 in the first place. Children with ADHD eat less omega-3-containing food and have less omega-3 in their bodies than children without ADHD, says Dr. Chang.
To test whether children with low omega-3 in their bodies could benefit from the supplement, researchers studied 92 Taiwanese children with ADHD aged between 6 and 18 for 12 weeks. These children were either given high doses of the omega-3 fatty acid or a placebo.
They found that children with the lowest blood levels of omega-3 showed improvements in focused attention and vigilance after taking the supplements. On the other hand, children with normal or high blood-levels of omega-3 showed no such improvements. What is worse, children with high pre-existing blood-levels of omega-3 showed negative effects on impulsivity symptoms.
The researchers caution that parents should consult with medical professionals before opting to give their children omega-3 supplements. "It is possible to have too much of a good thing, and parents should always consult with their children's psychiatrists since our study suggests there could be negative effects for some children," adds Dr Chang.
The study has been published in the Translational Psychiatry.