Research update: Food and children’s behaviour

Whether your child has a diagnosed behavioural disorder or is simply going through a difficult stage, latest research has confirmed that food can be a contributing factor. Nutritionist Tracy Morris reports on the three major links between food and behaviour.

Does your child display these behaviours?

• Inattentivness
• Forgetfulness
• Lack of organisation
• Acting impulsively
• Hyperactivity
• Anxiety or depression
• Aloofness
• Antisocial behaviour
• Unresponsive to others
• Restlessness
• Difficulty completing tasks
• Interrupting others
• Constant fidgeting

These behaviours can all be a normal part of a child’s development – however, research has shown they may be linked to diet.

1.  The basics

We all know that kids need to eat breakfast, eat balanced meals and eat regularly – and research has shown that these three habits can make a big difference to children with behavioural issues.

Breakfast

Several studies have indicated eating breakfast helps children perform better at school. Children are more attentive, less fidgety and recall more information in the classroom when they eat a nutritious breakfast, compared to when they don’t.

Take action

Always encourage your kids to eat breakfast. Any breakfast is better than nothing, however, emerging evidence shows that lower-GI foods may be a better choice.

Great breakfast options

• a boiled egg and toast soldiers
• baked beans served on a grainy bun
• porridge cooked with apple and served with a dollop of yoghurt
• 2 Weet-Bix with milk and sliced strawberries
• a ready-made breakfast drink such as Sanitarium Up&Go with a banana

Eating regularly

Behavioural, emotional and academic problems have been found to be more prevalent in hungry children, and both aggression and anxiety in children are strongly associated with hunger. Studies have also shown that being hungry reduces a young child’s tolerance to frustration and can make them more prone to tantrums and behavioural issues.

Take action

Ensure your kids are offered three main meals and two snacks each day. They may not eat it all but a regular supply of healthy foods is important to ensure stable blood glucose levels.

Great kids’ snack options.

• fresh fruit and yoghurt
• popcorn (air-popped)
• vege sticks with reduced-fat cream cheese
• fruit pottles with purée or jelly
• raisins and nuts

2.  Food intolerances

Covered the basics, but still suspect that your child’s behavioural issues are diet-related? Research shows that food intolerances could be to blame.

Natural food chemicals

For some children, a food intolerance to naturally-occurring food chemicals (salicylates, amines and glutamate) can worsen incidences of bad behaviour or behavioural disorders. When these chemicals are removed from the diets of food-sensitive children, their behaviour may improve significantly.

Take action

Parents who suspect certain foods may be triggering behaviour symptoms, may need to trial an elimination diet. This can be an extremely tricky process and should only be attempted with medical supervision.

Natural food chemicals and where to find them

• Salicylates are found in most fruit, some vegetables, herbs, spices, tea and flavour additives such as mint flavouring.
• Amines are found in cheese, chocolate, wines, beer, yeast extracts and fish products, and certain fruits and vegetables.
• Glutamate is found in most foods, as it acts as a natural flavour enhancer, and added monosodium glutamate (MSG) is often used in soups, sauces, snack foods and Asian cooking.

For more information, visit the Royal Prince Alfred Hospital Allergy Unit website www.sswahs.nsw.gov.au/rpa/allergy). You could also try reading Friendly Food: An Essential Guide to Avoiding Allergies, Additives and Problem Chemicals by Drs. Anne Swain, Velencia Soutter and Robert Loblay.

Food additives

For a small minority of the population, food additives (colours, preservatives and flavour enhancers) may cause adverse reactions, including behavioural issues. Australian research found a preservative commonly used to prevent bread from going mouldy, called calcium propionate (282), can cause irritability, restlessness, inattention and sleep disturbances in children prone to food sensitivities.

The UK has had a voluntary ban on six food colours since 2008, as research funded by the UK Food Standards Agency (FSA) suggested that consuming mixes of these food colours and the preservative sodium benzoate could be linked to increased hyperactivity in some children. The artificial colours implicated were: tartrazine (102), quinoline yellow (104), sunset yellow FCF (110), azorubine or carmoisine (122), ponceau 4R (124) and allura red AC (129). These colours have been used in a wide range of foods that tend to be brightly coloured, including some soft drinks, sweets, cakes and ice cream. The New Zealand Food Safety Authority has not banned these colours here as it does not consider the research to be robust.

It is very difficult to hide food colouring from parents in this type of research, so their expectations and beliefs have the potential to strongly influence how they rate children’s behaviour given different coloured drinks.

Take action

Some food additives help ensure the food is safe to eat, but colours are purely about aesthetics. If you believe your child is affected by food colourings then there’s no harm in avoiding them. Brightly-coloured foods are often high in sugar or fat so they are not ideal for any of us as everyday foods.

Nutrition deficiencies

While balanced, regular meals can help alleviate some behavioural issues, and removing foods that your child is sensitive to can also make a difference, studies have shown that boosting levels of particular minerals and nutrients may, for some children, help to improve behaviour.

Vital micronutrients – iron and zinc

Iron and zinc deficiencies have both been implicated in children’s behaviour. Under two years of age, a period of rapid brain development, iron deficiency appears to be the most serious and can result in long-term problems with attention and mood. Emerging research also shows that many children with ADHD have lower levels of zinc in their blood compared to healthy children. Improving zinc levels in children with ADHD has been shown to reduce symptoms of hyperactivity, impulsivity and impaired socialisation.

Take action

If you are concerned, get your child’s iron and zinc blood levels tested. Low levels can be improved by including rich sources of both minerals in your child’s diet. Supplementation should only take place under the guidance of a health professional, as iron and zinc are toxic in large doses.

Sources of iron and zinc

• lean beef and lamb
• iron-fortified rice cereal with puréed fruit (from six months of age onwards)
• iron-fortified breakfast cereal (eg. Weet-Bix) with fruit
• spaghetti bolognese
• baked beans on soy & linseed bread
• boiled eggs
• green vegetables – seaweed (try baby sushi), peas or spinach
• dairy foods – cheese, yoghurt (source of zinc only, not iron)
• Milo or Ovaltine for older children

Essential fats – omega-3s

Low levels of omega-3 fats have been found in kids with ADHD and autism. In these children, studies have shown improvements in disruptive behaviours, such as inattention, hyperactivity and impulsivity, following omega-3 supplementation. Even in ‘healthy’ children, increasing omega-3 intake may improve concentration and enhance the function of brain regions involved in attention.

Take action

The National Heart Foundation of Australia recommends children consume about 500mg per day of combined long-chain omega-3s (DHA and EPA). This can be achieved through a combination of the following:

• two to three serves of oily fish per week (eg. salmon or mackerel)
• food and drink enriched with marine omega-3s
• fish oil capsules or liquids (aim for a maximum of 500mg/day of DHA and EPA) sources of omega-3
• best source: oily fish (eg. fresh salmon or canned pink/red salmon)
• excellent source: white fish, other seafood
• good source: tuna and frozen fish fillets
• source: eggs, lean red meat or other omega-3-enriched foods (eg. Tip Top Up bread)

Food and autism

Unpublished research from the University of Sydney and the Royal Prince Alfred Hospital Allergy Unit (Sydney) has shown a clear link between diet and autism symptom management. When researchers removed certain foods and food additives from children’s diets, their ‘inner feelings of irritability’ vanished, according to participant and parent responses. Other dietary and complementary therapies include:

Gluten and casein-free diet

Anecdotally, there is some support for a diet that eliminates gluten and casein (a protein found in dairy products), however, this remains controversial. But, new Danish research has found significant improvements in autistic behaviours in some kids following the diet. Diet-sensitive autistic children, who show improvement on a gluten and/or casein-free diet, often react to artificial additives, too. As this diet can be highly restrictive, and may only be beneficial to kids who have an intolerance to gluten and casein, parents should only introduce this diet with the help of a health professional.

Vitamin and mineral supplements

Vitamins and minerals thought to improve autistic behaviour include vitamin B6, vitamin C and magnesium. However, at this stage there is not enough scientific evidence to justify supplementation for children with autism. Take caution as high doses of vitamin B6 can be dangerous.

What about sugar?

While many parents blame sugar for an excitable and hyperactive child, several well-designed studies have failed to prove the link.

The verdict

All children, including those with ADHD and autism, should aim to eat a balanced diet, based on minimally processed whole foods. If your child appears to have behavioural difficulties, research shows that altering their diet may help – but it’s important to seek help from a dietitian, to investigate possible food-related causes.

It is also worth noting that behavioural issues can stem from a variety of non-diet-related factors, so if you are concerned about your child’s behaviour, it is a very good idea before doing anything else to seek assistance from a qualified health professional such as a child psychiatrist