Free fatty acid supplementation produced small but significant reductions in ADHD symptoms even with probably blinded assessment s , although the clinical significance of these effects remains to be determined .
Artificial food color exclusion produced larger effects but often in individuals selected for food sensitivities .
OBJECTIVE Nonpharmacological treatments are available for attention deficit hyperactivity disorder ( ADHD ) , although their efficacy remains uncertain .
The authors undertook meta-analyses of the efficacy of dietary ( restricted elimination diets , artificial food color exclusions , and free fatty acid supplementation ) and psychological ( cognitive training , neurofeedback , and behavioral interventions ) ADHD treatments .
Effects of a restricted elimination diet on the behaviour of children with attention-deficit hyperactivity disorder (INCA study): a randomised controlled trial
BACKGROUND The effects of a restricted elimination diet in children with attention-deficit hyperactivity disorder ( ADHD ) have mainly been investigated in selected subgroups of patients . We aim ed to investigate whether there is a connection between diet and behaviour in an unselected group of children . METHODS The Impact of Nutrition on Children with ADHD ( INCA ) study was a r and omised controlled trial that consisted of an open-label phase with masked measurements followed by a double-blind crossover phase . Patients in the Netherl and s and Belgium were enrolled via announcements in medical health centres and through media announcements . R and omisation in both phases was individually done by r and om sampling . In the open-label phase ( first phase ) , children aged 4 - 8 years who were diagnosed with ADHD were r and omly assigned to 5 weeks of a restricted elimination diet ( diet group ) or to instructions for a healthy diet ( control group ) . Thereafter , the clinical responders ( those with an improvement of at least 40 % on the ADHD rating scale [ ARS ] ) from the diet group proceeded with a 4-week double-blind crossover food challenge phase ( second phase ) , in which high-IgG or low-IgG foods ( classified on the basis of every child 's individual IgG blood test results ) were added to the diet . During the first phase , only the assessing paediatrician was masked to group allocation . During the second phase ( challenge phase ) , all persons involved were masked to challenge allocation . Primary endpoints were the change in ARS score between baseline and the end of the first phase ( masked paediatrician ) and between the end of the first phase and the second phase ( double-blind ) , and the abbreviated Conners ' scale ( ACS ) score ( unmasked ) between the same timepoints . Secondary endpoints included food-specific IgG levels at baseline related to the behaviour of the diet group responders after IgG-based food challenges . The primary analyses were intention to treat for the first phase and per protocol for the second phase . INCA is registered as an International St and ard R and omised Controlled Trial , number IS RCT N 76063113 . FINDINGS Between Nov 4 , 2008 , and Sept 29 , 2009 , 100 children were enrolled and r and omly assigned to the control group ( n=50 ) or the diet group ( n=50 ) . Between baseline and the end of the first phase , the difference between the diet group and the control group in the mean ARS total score was 23·7 ( 95 % CI 18·6 - 28·8 ; p<0·0001 ) according to the masked ratings . The difference between groups in the mean ACS score between the same timepoints was 11·8 ( 95 % CI 9·2 - 14·5 ; p<0·0001 ) . The ARS total score increased in clinical responders after the challenge by 20·8 ( 95 % CI 14·3 - 27·3 ; p<0·0001 ) and the ACS score increased by 11·6 ( 7·7 - 15·4 ; p<0·0001 ) . In the challenge phase , after challenges with either high-IgG or low-IgG foods , relapse of ADHD symptoms occurred in 19 of 30 ( 63 % ) children , independent of the IgG blood levels . There were no harms or adverse events reported in both phases . INTERPRETATION A strictly supervised restricted elimination diet is a valuable instrument to assess whether ADHD is induced by food . The prescription of diets on the basis of IgG blood tests should be discouraged . FUNDING Foundation of Child and Behaviour , Foundation Nuts Ohra , Foundation for Children 's Welfare Stamps Netherl and s , and the KF Hein Foundation
Free fatty acid supplementation produced small but significant reductions in ADHD symptoms even with probably blinded assessment s , although the clinical significance of these effects remains to be determined .
Artificial food color exclusion produced larger effects but often in individuals selected for food sensitivities .
OBJECTIVE Nonpharmacological treatments are available for attention deficit hyperactivity disorder ( ADHD ) , although their efficacy remains uncertain .
The authors undertook meta-analyses of the efficacy of dietary ( restricted elimination diets , artificial food color exclusions , and free fatty acid supplementation ) and psychological ( cognitive training , neurofeedback , and behavioral interventions ) ADHD treatments .