The importance of Gut Brain Connection for our Children

Food for the Brain

Nutrition & ADHD/Hyperactivity – What Works


Hyperactivity can be due to too much sugar in the diet (and remember that  foods like pasta, bread, crackers, rice all provide glucose to a body). It can also be the form of sugar that is the problem; or that the diet is overbalanced in certain food groups; or abnormal glucose metabolism.

A study of 265 hyperactive children found that more than three­ quarters of them displayed abnormal glucose tolerance– that is, their bodies were less able to handle sugar intake and maintain balanced blood sugar levels.

If the levels of glucose in a child’s blood seesaws continually then it can trigger wild fluctuations in their levels of activity, concentration, focus and behaviour. These, of course, are also the symptoms of ADHD.

Side effects? If sugar consumption is high and it is withdrawn suddenly, withdrawal symptoms such as headaches and irritability may ensue. Better to make gradual reductions to avoid this, without losing sight of the eventual goal of a low sugar diet.


Omega­3s have a clearly calming effect on many children with hyperactivity and ADHD. And many children with ADHD/hyperactivity have visible symptoms of essential fat deficiency such as excessive thirst, dry skin, eczema and asthma.

It is also interesting that boys, whose requirement for essential fats is much higher than girls’, are also much more likely to have ADHD. Researchers have theorised that ADHD children may be deficient in essential fats not just because their dietary intake from foods such as seeds and nuts is inadequate (though this is not uncommon), but also because their need is higher, their absorption is poor, or they are unable to convert these fats well into EPA and DHA, and from DHA into prostaglandins, which are also important for brain function.

It’s also interesting that the conversion of essential fats can be limited by foods that commonly cause symptoms in children with ADHD, such as wheat, dairy and foods containing salicylates. (See below for more on salicylates) This conversion is also hindered by deficiencies of the various vitamins and minerals that help the enzymes making these conversions – vitamins B3 (niacin), B6, C, biotin, zinc and magnesium. Zinc deficiency is common in children with ADHD.


Although it is unlikely, on the basis of the studies to date, that ADHD is purely a deficiency disease, most children with this diagnosis are deficient in certain key nutrients, and do respond very well.

Zinc and magnesium are the most commonly deficient nutrients in people with ADHD. In fact, symptoms of deficiency in these minerals are very similar to the symptoms of ADHD. Low levels of magnesium, for instance, can cause excessive fidgeting, anxious restlessness, insomnia, coordination problems and learning difficulties (if accompanied by a normal IQ).

Polish researchers studying 116 children with ADHD for their levels of magnesium found that 95 per cent of them were deficient in it – a much higher percentage than that among healthy children. The team also noted a correlation between levels of magnesium and severity of symptoms. Supplementing 200mg of magnesium for six months significantly reduced hyperactivity in the children with ADHD, but behaviour in the control group, who received no magnesium, worsened.


Of all the avenues so far explored, the link between hyperactivity and food sensitivity is the most established and worthy of pursuit in any child showing signs of ADHD. Food allergies can be of two types: Type 1 in the classical, severe and immediate allergy most commonly associated with peanuts and shellfish. This allergy involves an antibody called IgE and most people discover if they have this type of allergy early in life since the reaction is so immediate and severe. The second type, which we will call Type 2 involves the IgG antibody which works in quite a different way. Symptoms of these allergies can be many and varied and may take many hours to appear. These allergies often go undetected for this reason and are classified as intolerances.

A study by Dr Joseph Bellanti of Georgetown University in Washington DC found that hyperactive children are 7 times more likely to have food intolerances than other children.

Children with ADHD/hyperactivity may also have a sensitivity to additives and preservatives. A separate investigation by the Hyperactive Children’s Support Group found that:

  • 89% of children with ADHD reacted to food colourings,
  • 72% to flavourings,
  • 60% to MSG,
  • 45% to all synthetic additives/ preservatives,
  • 50% to cow’s milk,
  • 60% to chocolate and
  • 40% to oranges.

Symptoms strongly linked to food intolerances include nasal problems and excessive mucus, ear infections, facial swelling and dark circles under the eyes, tonsillitis, digestive problems, bad breath, eczema, asthma, headaches and bedwetting.

Some parents have also reported success with the Feingold diet, removing not only all artificial additives but also foods that naturally contain compounds called salicylates.

Researchers at the University of Sydney in Australia found that 3/4 of 86 children with ADHD reacted adversely to foods containing salicylates. These include prunes, raisins, raspberries, almonds, apricots, canned cherries, blackcurrants, oranges, strawberries, grapes, tomato sauce, plums, cucumbers and Granny Smith apples. As the list of foods containing salicylates is very long and contains many otherwise nutritious foods, cutting them all out should be considered only as a secondary course of action, and must be carefully planned and monitored by a nutritional therapist.

Understanding how a low ­salicylate diet helps hyperactive children does offer a useful alternative to such a drastic course of action. Salicylates inhibit the conversion and utilisation of essential fats, which we know are often low in hyperactive children. So instead of avoiding salicylates, it may help to simply increase the supply of essential fats.

If you are overwhelmed and in need of support Ruth specialises in working with families with children who have a diagnosis of ADHD as well as those who suffer with hyperactivity and mood disorders.