För första gången ställer sig denna väletablerade skolmedicinska skrift bakom den kontroversiella uppfattningen att adhd har samband med vad vi äter. Det är åsikter som hittills enbart hävdats inom den alternativa medicinen utan stöd från etablerade experter.
– Av de 41 barn som fullföljde kostomläggningen kunde vi påvisa märkbara förbättringar hos 32, det vill säga 64 procent, säger professor Jan Buitelaar från Radboud-universitet i Nijmegen som lett studien.
– Vi såg också att dessa barn försämrades när de började äta normalt igen. Det innebär att så mycket som mer än vartannat fall av adhd skulle kunna ha kostanknytning, slår han fast.
I Lancet pläderar nu forskarna för att alla med adhd borde få genomgå ett liknande kosttest för att fastställa eventuella samband med maten och på så sätt skräddarsy en kost för varje individ.
– En sådan insats kräver resurser och inte minst utbildning framför allt av läkare och dietister. Men det skulle innebära ett viktigt framsteg. Vi skulle till exempel kunna begränsa behandling med läkemedel till enbart adhd-drabbade som inte är kostkänsliga, säger Jan Buitelaar.
Han avråder dock bestämt från alla försök att testa denna kostomläggning på egen hand. Det måste ske under ledning av läkare och specialister.
RESTRICTING the diets of children with attention deficit hyperactivity disorder to omit allergy-causing foods can improve symptoms substantially in about two-thirds of cases. Researchers compared the effects on behaviour of giving 50 children aged four to eight a restricted diet, against another 50 eating normal healthy fare, and reported parents and teachers found significant improvements in behaviour in 64 per cent of the restricted diet group.
The findings reinforce theories that food may play a role in triggering ADHD in some children – but they also debunk some current methods that claim to detect which foods may be troublesome.
Of the 50 children given the restricted diet – comprising rice, meat, vegetables, pears and water, plus potatoes, fruits and wheat if they could tolerate them – 41 completed the five-week course.
None of the 100 children in the trial were being treated with ADHD drugs, and the study did not select children previously diagnosed with food allergies. Those already on a restricted diet were excluded.
No significant improvements in behaviour were seen in the children given the normal diet, whereas 32 of the 41 on the restricted diet did improve.
Of these 32, 30 were then subjected to a ”challenge”, which involved them having three foods reintroduced into their diets.
These three foods – which were different for each child – had been previously been shown to trigger either a high or a low increase in blood levels of an immune system antibody called immunoglobulin G (IgG).
In half the 30 cases, the children were first given three foods that triggered a big rise in IgG levels, followed by three foods that triggered a small IgG increase.
In the other children, low IgG foods were given first, followed by the foods that caused a bigger effect.
The researchers found 19 of the 30 children experienced an increase in their ADHD symptoms after the foods were reintroduced – but that there was no significant difference between the groups given high-IgG or low-IgG foods first.
The Dutch authors of the research, whose study was published yesterday by the British-based medical journal The Lancet, said this suggested there was little validity to the practice of eliminating foods purely on the basis of IgG blood tests, which they said was common among some complementary medicine practitioners.
The authors said their findings showed ”considerable effects of a restricted elimination diet in an unselected group of children with ADHD, with equal effects on ADHD and oppositional defiant disorder”.
”Therefore, we think that dietary intervention should be considered in all children with ADHD, provided parents are willing to follow a diagnostic restricted elimination diet for a five-week period, and provided expert supervision is available,” they wrote.
”Children who react favourably on this diet should be diagnosed with food-induced ADHD and should enter a challenge procedure, to define which foods each child reacts to, and to increase the feasibility and to minimise the burden of the diet.
”In children who do not show behavioural improvements after following the diet, standard treatments such as drugs, behavioural treatments, or both should be considered.”
In an accompanying comment in the journal, US child and adolescent psychiatrist Jaswinder Ghuman, of the University of Arizona, wrote the study was ”well-designed and carefully done… and provides an additional treatment option for some young children with ADHD”.
However, Associate Professor Ghuman said 36 per cent of the children either did not respond to the elimination diet, or their parents did not comply with the diet.
In addition, there were also other factors that could have coloured the findings, such as the fact that parents and teachers were aware of whether children were on the elimination diet or not.
”Therefore, in both the control and elimination diet groups, the beliefs and expectations of parents and teachers about changes in ADHD symptoms could have been influenced by this knowledge,” she wrote.
Läs studiesammanfattningen här: http://www.thelancet.com/journals/lancet/article/PIIS0140-6736%2810%2962227-1/abstract
