Food For Thought


Diets: cave man, paleo, “ape,” low carb, low glycemic, zone, ketogenic, specific carbohydrate, GAPS, “grain brain,” “wheat belly,” mitochondrial diet: why is there so much interest in these diets? What are they targeting? Is it gut dysbiosis/inflammation or food allergies, or insulin dysregulation, or gluten intolerance, the optimal primate food, or what?? Is there perhaps a unifying explanation for their widespread applicability?

Before you read the commentary below, the short answer is that there is good evidence that these diets (one could almost say, “this diet”) present a potent way to help many children with autism. And by looking at what is understood to be the sources of benefit from these different versions, we may come to realize how many good reasons there are to consider adopting a diet low in carbohydrates and high in good fats. In other words, it makes sense to look beyond the common indications: food intolerances and digestive disruptions, in deciding which children can be helped by a change in diet.

One common feature with all of these diets is resistance to their acceptance by organized medicine. Reflecting on their history, this is likely due, in part, to unclear mechanisms of action, collisions with prevailing “wisdom” about healthy eating, and a strong food lobby for processed, sugary foods (take a walk through the middle aisles of the grocery store and make a count of the breakfast cereals, chips and crackers, breads and desserts, sweetened beverages and juices if you doubt the influence of these foods in our personal and national economy). With deeper research into nutritional and digestive physiology, the human microbiome, and neuroimmunoendocrinology, a solid conceptual basis for these similar diets is being established, and their utility is gradually “seeping in” to ordinary medical thinking and therapeutics. A second common feature of these diets is their emphasis on simple unprocessed foods, particularly vegetables and meats. Another common feature is that they are labor intensive, requiring home preparation of most of the foods (thus giving the consumer good knowledge of the actual ingredients, and also the touch and energy of a person known to the one eating). Yet another common feature is that the eater experiences resistance to the changes involved (sometimes including addictive-type withdrawal). After briefly discussing some of these diets, I’ll return to consider the above questions, and some general thoughts about diet and health.

My first experience with these diets was with the cave man diet (and I’ll here include paleo and ape diets as almost identical), taught me by the Society for Clinical Ecology in 1981. This diet was developed as a diagnostic approach to food allergies, aiming to eliminate the most common food allergens: grains, dairy, eggs, legumes, nuts, sugar, potatoes, yeast, food additives. Persuading patients to try this diet for two weeks was not easy; however, I well remember one of my first patients who took on the diet for the recommended trial period. At our two week follow-up, she enthusiastically reported the clearing of all of her symptoms, and asked if she could remain on the diet long term, instead of challenging the foods she’d been avoiding. She received my approval, recognizing that this diet has been well tested over the history of primates and stone age, pre-agricultural man. The general understanding at that time, was that the diet was treating food intolerances, with symptomatic improvement attributed to removal of offending foods.

The low carbohydrate diet, popularized by Robert Atkins, has been followed by millions of people with many different health conditions. I would include the ketogenic diet, zone diet, low glycemic diet as close relatives of the Atkins diet. First recorded publication on this dietary approach was in 1863 (Letter on Corpulence Addressed to the Public), by William Banting, a carpenter and eminent undertaker, who struggled with obesity from a young age. He rigorously followed many different exercise and dietary programs without success. After years of unsuccessful efforts, guided by the best available medical counsel, he encountered William Harvey MD. Inspired by the work of Claude Bernard (one of the fathers of the science of physiology), Dr. Harvey advised him to undertake a low carbohydrate diet (eliminating sweets, potatoes, grains, beer and sweet alcoholic drinks). In six months he lost 25% of his body weight, returning to normal weight, and also found lasting relief of a panoply of chronic symptoms. Despite Banting’s success, the publication of his book and development of a foundation to promote the diet, it was met with huge resistance from the medical profession, and Dr. Harvey was criticized and ostracized. The general failure of acceptance of their findings is perhaps attributable to the lack of an accepted theory on why the diet worked, despite the fact that it did work for many obese people at that time. At this time, the ketogenic diet and the modified Atkins diet are well recognized as effective in control of seizures, and as potentially beneficial in neurodegenerative diseases (and possibly one form of brain tumor, the astrocytoma).

The specific carbohydrate diet (SCD, and GAPS, an updated version) was developed by Sidney V. Haas (author of 1951 textbook: The Management of Celiac Disease), and popularized by Elaine Gottschall, (Food and the Gut Reaction 1987, second edition: Breaking the Vicious Cycle 1994) whose daughter was cured of ulcerative colitis by following Haas’ diet. The SCD was initially directed toward treatment of inflammatory bowel disease (Crohn’s and Ulcerative Colitis) and celiac disease, and have produced remarkable benefit, even clearing of their disease in some IBD patients in my practice, since I met Elaine in the mid 1990’s. The conceptual basis for the diet is that it produces positive changes in gut flora, reduction in fermentation of undigested carbohydrates, and resultant decrease in bowel inflammation. SCD and GAPS approaches have been extended to patients with autism, bringing tremendous benefit to thousands of these children. On the other hand, Wikipedia’s article on SCD concludes: “…however, scientific evidence of the diet’s effectiveness is lacking, and the diet may pose a health risk due to lack of nutritional quality.” We hear these comments, despite seminal work at Harvard Med Center by the GI team, demonstrating loss of intestinal disaccharidase enzyme function in a very substantial portion of children with autism, and several published studies (one from U Mass Med Center, one from Seattle Children’s Hospital) showing clinical improvements in patients with inflammatory bowel disease who have been treated with this diet.

The “wheat belly” and “grain brain” diets are again very similar to the low carb dietary approaches, adding a particular focus on gluten and gliadin constituents of wheat. We have found in autism that many children have an opiate-like response to gluten (and to casein from milk products), with improvements in brain and gut function (and often a painful withdrawal period at first) after removing these foods strictly from their diet. As mainstream medical awareness of gluten intolerance expands, we are learning that many autoimmune diseases are aggravated by gluten intolerance, whether or not the patient has celiac disease. And so, for autoimmune thyroiditis, rheumatoid arthritis, lupus, type 1 diabetes, and even MS, a patient may be encouraged to avoid gluten as a possible trigger. Also, the risk of neurodegenerative diseases such as Alzheimer’s, Parkinson’s Disease, and Amyotrophic Lateral Sclerosis is increased in people with insulin resistance or type diabetes.

Terry Wahls’ mitochondrial diet has demonstrated marvelous healing of her own multiple sclerosis. This diet has been further studied in her medical practice, and has shown promising results thus far in some of her MS patients. Again, this diet is a low carbohydrate diet, which emphasizes large amounts of high antioxidant fruits and vegetables.

These diets are often referred to as anti-inflammatory; how might this be so? There are a number of considerations to explore.

  1. Vegetables and many fruits (especially berries, which are incidentally the lowest carbohydrate fruits) are an excellent source of many phytonutrients, which stimulate our antioxidant defenses and help reduce inflammation. Consuming increased amounts of these foods, versus the nearly empty calories found in processed foods, will enhance many vital functions in the body.
  2. Processed foods commonly contain toxic substances: food additives, hydrogenated fatty acids, amino acids which can be isomerized by processing—these substances and others (such as synthetic vitamins which function poorly or not at all as intended) may contribute to inflammation.
  3. Processed foods also contain large amounts of salt, sugar, other sweeteners, in excess of what we commonly use in home-made food. High fructose intake (found particular in corn syrup and agave syrup) is associated with increase insulin resistance, which contributes to chronic inflammation.
  4. In general, processing of foods removes nutrients found in the whole food—such nutrients as fiber, essential fatty acids, trace minerals and fragile vitamins as folic acid. Fortification of processed foods is incomplete, as we have not yet identified all the required nutrients for human health. Reduced dietary fiber contributes to intestinal disturbances, essential fatty acids are important in regulating inflammation and cellular function, and trace nutrients are involved in many body functions involving immune activities, neurotransmitter function, energy production, and cellular communication.
  5. Processing of foods tends to increase the caloric density, thus increasing the tendency to ingest more calories. This issue, along with the effects of food additives such as MSG, which directly stimulates insulin release, may contribute directly to obesity, and the increased inflammation inherent to obesity.
  6. High glycemic foods (foods which raise the blood sugar quickly and extensively) stimulate insulin release. It is now recognized that insulin is a pro-inflammatory molecule, and that insulin resistance (with higher insulin levels, as is found in most overweight people, in metabolic syndrome, and in type 2 diabetes) is associated with increased risk of dementia and other inflammatory conditions (such as joint disease). Related to these effects is the documented benefit of the diabetic drug Actos in autism, acting as an anti-inflammatory through NFkappaB and PPAR gamma signaling modulation. In essence, diets which reduce the blood sugar rise with meals also reduce insulin levels and thus may reduce inflammation. This is an important consideration in autism, where gut and brain inflammation are strong contributors to the pathology and symptoms children experience.

In summary, it makes sense to explore dietary changes in children with autism and related conditions. Beyond the first common step of eliminating gluten and casein is to begin to focus on reducing carbohydrates, particularly the quick acting and concentrated carbohydrates. These are found in large amounts in all grains and grain substitutes, potatoes, sugars, dried fruits and fruit juices, and in certain fruits (bananas, watermelon, dates, etc.). There is strong convergent evidence supporting the potential value of a diet low in carbohydrates, rich in vegetables and healthy fats (coconut, omega III, olive, nuts and seeds, moderate meats, and clean fish {hard to find}) generous in low carb fruits (berries in particular, in not phenol sensitive), and moderate in protein in children with special needs or chronic illness.

A good way to start would be the low glycemic diet, which aims to avoid foods with a glycemic index above 50 and a glycemic load above 10. Harvard Health Publications presents a table of glycemic index and load values for 100 foods (, which will help you to begin evaluating food choices for your child. A much longer list of over 2400 international foods is provided at (, and can be used to research less common foods your child may be willing to consume. Remember, this diet is very similar to the diet which primates have consumed since time immemorial. There is a reason why we are told not to feed the monkeys at the zoo—our diet can make them sick!

Clearly, modifying the diet of a child with special needs is a daunting and sometimes terrifying proposition. Their eating habits, addictions, sensory issues, and in many cases, poor health and vitality all contribute to immense difficulties in accomplishing desired changes. In addition, it is difficult to help special needs children to understand the reason for removing favorite foods, as they will generally prefer to stay with the status quo. However despite all the challenges, we have seen immense progress in children whose parents succeed at major dietary interventions; it is worth all the effort in order to maximize their chances to make good progress. I have found it often very helpful if the whole family follows a similar program, and all may benefit from doing so, in addition to the support provided to the child of special concern by doing this. May you be rewarded with a healthy happy child and family!