Scientific evidence for the effects of food on children's health, behaviour and learning


6 Feb 2011 Special diet helps two-thirds of ADHD children stop medicine.

A restrictive diet for children suffering from ADHD can be so beneficial that many of them can stop taking medicine altogether, according to a Dutch study published in The Lancet yesterday. The research involved 100 children aged four to eight. Fifty of them followed an elimination diet – removing all known problem foods until some of them consumed only rice, turkey, pear, vegetables and water. After five weeks, two-thirds of the children on the special diet no longer had any behavioural problems. There was no difference in the behaviour of the control group on a 'healthy' diet. The children were followed for a year, with foodstuffs being added back into their diet to determine what caused the hyperactive reaction. IgG tests (as recommended by some doctors) were found not to be helpful compared to food challenges.

The researchers found 'considerable effects of a restricted elimination diet ... with equal effects on ADHD and oppositional defiant disorder'. They concluded 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.

The Few Foods Diet used by the Dutch study is not new but it is the first time it has been trialled on so many children for such a long time.

In 1985, a similar trial of the RPAH Elimination Diet with 140 behaviourally disturbed children found that nearly two thirds (61%) improved significantly and that a suitable diet could usually be devised for each child within three months. We recommend the RPAH Elimination Diet supervised by an experienced and supportive dietitian to members of the Food Intolerance Network because it is equally effective and much easier to use. 

Further information


2 Feb 2011 Additive-free school trial goes French

After watching the results of our 2007 Nana Glen Primary School NSW additive free trial, seven schools in France are intending to carry out similar trials. See the trial and how we did it: Eating for Success!


19 Jul 2010 Artificial colours pose risks of cancer, hyperactivity in children, and allergies, and should be banned

According to a new report by the Center for Science in the Public Interest, and a top government scientist agrees, and says that food dyes present unnecessary risks to the public. See Food Dyes: A Rainbow of Risks


From July 21st 2010, a warning about artificial colours

"May have an adverse effect on activity and attention in children" must be used on foods in the EU. This warning is not required in Australia where it is still up to parents to read labels.

Further information


May 2009 A study of nearly 3000 teenagers at the Centre for Child Health in WA has found that the Western dietary pattern is significantly associated with poor behaviour.

This study showed that foods such as snacks, takeaway food, confectionery, processed and red meats, and other refined foods were associated with increased depression or aggression and that better behavioural outcomes were associated with a higher intake of fresh fruit and leafy green vegetables. But correlation is not causation.  

What this study did not show is that micronutrients such as folates and other vitamins have anything to do with such behaviours. That is only speculation by the authors who chose to completely ignore the fact that additives in the western diet have been consistently associated with bad behaviours in over thirty years of research. 

See "The Association between dietary patterns and mental health in early adolescence":


The Stevenson University of Southhampton Study

The Lancet 2007 DOI:10.1016/S0140-6736(07)61306-3

Food additives and hyperactive behaviour in 3-year-old and 8/9-year-old children in the community: a randomised, double-blinded, placebo-controlled trial

Donna McCann, Angelina Barrett, Alison Cooper, Debbie Crumpler, Lindy Dalen, Kate Grimshaw, Elizabeth Kitchin, Kris Lok, Lucy Porteous, Emily Prince, Edmund Sonuga-Barke, John O Warner, Jim Stevenson


Background We undertook a randomised, double-blinded, placebo-controlled, crossover trial to test whether intake of artificial food colour and additives (AFCA) affected childhood behaviour.

Methods 153 3-year-old and 144 8/9-year-old children were included in the study. The challenge drink contained sodium benzoate and one of two AFCA mixes (A or B) or a placebo mix. The main outcome measure was a global hyperactivity aggregate (GHA), based on aggregated z-scores of observed behaviours and ratings by teachers and parents, plus, for 8/9-year-old children, a computerised test of attention. This clinical trial is registered with Current Controlled Trials (registration number ISRCTN74481308). Analysis was per protocol.

Findings 16 3-year-old children and 14 8/9-year-old children did not complete the study, for reasons unrelated to childhood behaviour. Mix A had a significantly adverse effect compared with placebo in GHA for all 3-year-old children (effect size 0⋅20 [95% CI 0⋅01–0⋅39], p=0⋅044) but not mix B versus placebo. This result persisted when analysis was restricted to 3-year-old children who consumed more than 85% of juice and had no missing data (0⋅32 [0⋅05–0⋅60], p=0⋅02). 8/9-year-old children showed a significantly adverse effect when given mix A (0⋅12 [0⋅02–0⋅23], p=0⋅023) or mix B (0⋅17 [0⋅07–0⋅28], p=0⋅001) when analysis was restricted to those children consuming at least 85% of drinks with no missing data.

Interpretation Artificial colours or a sodium benzoate preservative (or both) in the diet result in increased hyperactivity in 3-year-old and 8/9-year-old children in the general population.

Stevenson2007   Stevenson2008


Other key scientific references on the effects of food additives on behaviour, health and learning

Abstracts for most of the articles listed below are available on and full details of the references.

In the US in 1999, a quarter century review of 23 controlled studies regarding diet and behaviour concluded that '17 of the studies found evidence that some children's behaviour significantly worsens after they consume artificial colours or certain foods such as wheat or milk' (Jacobson MF and Schardt MS 1999) and  'research with electroencephalography (EEG) indicates that certain foods trigger physiological changes in sensitive individuals' (Uhlig, Merkenschlager et al. 1997). This review can be easily downloaded from or here

A review commissioned by the US National Institutes of Mental Health concluded that success of dietary management depends on the type of diet used (Arnold 1999).

 The Feingold diet introduced in the US in 1970s is a low chemical elimination diet excluding food additives and certain foods containing salicylates (Feingold 1968; Feingold 1977; Feingold 1979).

In Australia, major clinical research concerning the effects of food additives and salicylates led to the development of low chemical elimination diets excluding more additives and more salicylates than the Feingold diet as well as biogenic amines in chocolate and other foods, and natural glutamates. This research was carried out with 20,000 patients over 20 years by the Royal Prince Alfred Hospital Allergy Unit and identified nearly 50 problem-causing food additives (artificial colours, annatto natural colour, sorbates, benzoates, sulphites, nitrates, propionates, gallates, TBHQ, BHA, BHT and MSG). Unfortunately, comparatively little has been published in peer reviewed journals although a wide range of food intolerance symptoms from children's behaviour to asthma, eczema, urticaria, irritable bowel symptoms, migraine and depression have been found to improve on diet. (Loblay RH and Swain AR; Allen DH, Van Nunen S et al. 1984; Swain, Soutter et al. 1985; Clarke L, McQueen J et al. 1996; Hodge, Yan et al. 1996; Parker and Watkins 2002).

Swain et al 1985

Clarke et al 1996

In a trial of the LALS diet (low additive, low salicylate), nearly 80% of 516 children improved significantly(Breakey, Hill et al. 1991) and in an open trial of the Failsafe diet (free of additives, low in salicylates, amines and flavour enhancers), 100% of 27 children who completed 2-3 weeks of their elimination diet improved significantly (Dengate and Ruben 2002).

Other diets that have been used successfully to reveal the effects of food additives and other foods include the Few Foods or oligoantigenic diet, and the ketogenic diet. The Few Foods diet, developed in the UK, involves wholefood exclusion and has been used for children's behaviour, migraine, epilepsy, enuresis and a wide range of other food intolerance symptoms although it is considered by many to be difficult to follow (Bennett CPW, McEwen LM et al. 1998) (Egger, Carter et al. 1983; Carter, Egger et al. 1985; Egger, Carter et al. 1985; Egger, Carter et al. 1989; Egger, Carter et al. 1992; Carter, Urbanowicz et al. 1993; Schulte-Korne, Deimel et al. 1996; Schmidt, Mocks et al. 1997; Pelsser and Buitelaar 2002). 

The ketogenic (low carbohydrate) diet has been used for eight decades to treat children's epilepsy. More recently, behaviour, autism and depression have been found to improve on this diet (Pulsifer, Gordon et al. 2001; Evangeliou, Vlachonikolis et al. 2003; Murphy, Likhodii et al. 2004; Murphy, Likhodii et al. 2005). Since the ketogenic diet excludes many processed foods as well as many fruits and vegetables, in practice it is a low additive, low salicylate diet.

More complete list of scientific references

The information given is not intended as medical advice. Always consult with your doctor for underlying illness. Before beginning dietary investigation, see our list of experienced and supportive dietitians 

© Sue Dengate March 2011