This week, the nutrition blog returns to the subject of restrictive diets, to look at the GAPS diet that has been advocated, although not by any mainstream scientific body or evidence, for children with autism spectrum disorder (ASD).
What is GAPS?
GAPS stands for Gut and Psychology Syndrome. Proponents of the GAPS diet put forward that a wide variety of health problems can be traced solely to an imbalance of gut microbes, and that autism as well as attention deficit hyperactivity disorder (ADHD), schizophrenia, epilepsy, depression are all digestive disorders. The unproven GAPS hypothesis is a single cause explanation that counters the complexity of the development of these conditions. It suggests that factors in the modern world drive the imbalance of gut microbes that leads to toxins being produced, which prevent the processing of sensory information in the brain. Such factors include antibiotics, lack of breastfeeding, processed foods and oral contraceptives. Worryingly, vaccinations in young children are also put forward as harmful.
What foods are restricted?
In brief, the GAPS diet is a phased diet intended to heal the gut in 1-2 years, and that involves the exclusion of a number of foodstuffs. Restricted foods include sugar, tinned food, grains (rice, corn, rye, oats, wheat and anything made of wheat flour, buckwheat, quinoa, millet, couscous, spelt, semolina, tapioca), starchy vegetables, milk, fruit juice, beans, pulses, coffee and soya. It allows certain vegetables and fruits, meats, fats, nuts, along with bone broths, the latter seeming to be having something of a surge in popularity in the media recently. The GAPS diet starts with a very limited introductory phase, and other foods are gradually added, with some interesting additions along the way such as fermented foods, raw organic egg yolks, homemade raw milk yogurt and ghee.
Detoxification (a current buzz word) through juicing or fasting is also encouraged. But it is good to be mindful that detoxification medically speaking is done by the liver – not by a glass of juice.
No published evidence to support GAPS
The relationship between autism, diet and gut flora is a fascinating area. We are increasingly recognising that gut microbiota can have an impact on health. However, there is no published evidence to support GAPS, and, without testing, there is no way to know whether it benefits or harms patients.This diet is targeted at young children, yet the early introductory stages may not provide adequate nutrition.
Behaviour in children with ASD is complex and it is not hard to see that parents faced with conventional medicine that does not meet their expectations look elsewhere for help. We should not forget that dietary changes can help children. There are certain aspects of GAPS that may be appropriate for a child with certain issues such as coeliac disease or cow’s milk allergy. We are in pressing need of more research to really understand what aspects of the diet may underlie anecdotal benefits. We need to be able to define more clearly the prevalence of possible undiagnosed conditions that may respond to diet or medication, but that would not be as restrictive, expensive or inconvenient as the GAPS diet, yet may offer the same improvements.