Can Diet and Biomedical Approach Really Improve Behavior and Developmental Disorders?


I completely understand the skepticism.

Because I was a skeptic at one point. I had heard “rumors” of diet changes helping kids with SPD/ADHD/Autism/Developmental Delays/Behavioral Disorders but I didn’t truly believe it. I was trained as a conventional medicine Physician Assistant and nowhere in our training did it mention nutrition as it relates to Behavioral disorders or developmental delays in children. I completely wrote off the notion as “crazy” and not “evidence-based medicine”. That is, until I was a parent in the trenches.

We were in survival mode. I had two children who were diagnosed with Sensory Processing Disorder and a newborn and life was HARD!!! We were barely functioning, just maintaining the household while also both working full time (demanding) jobs. I became desperate and thought to myself “what do I have to lose??” And so began our journey in Functional Medicine.


The improvements in our family have been indescribable. We are actually the family I pictured when I was a little girl dreaming of having a family one day. There are hardly any sensory meltdowns. My daughters PANS (more info here) is under control and her rigid/inflexible behavior and thought processes are tamed down dramatically. We are finally sleeping (and pooping). And the list goes on and on… (for more on our story, read here).

Diet Changes and Behavior

One of the most common diet recommendations for children with ADHD, Autism or Sensory Processing Disorder (SPD) is a gluten-free, casein-free diet. This diet often gets a lot of criticism by the mainstream medical community because they report there is not enough evidence to say this diet will lead to health benefits. Here is my thought: What can it hurt? If you are in the trenches and at your wits end like I was, then it is absolutely worth it to try a new diet in hopes that it helps your child function and feel better. And if you can avoid any harmful or unnecessary medication because you decided to remove gluten or dairy from your child’s diet, then I consider that a victory. I linked a case report below to the results of a 3 year old boy with Autism who was placed on a gluten-free, casein-free diet and here is an excerpt of the clinical findings:

After 2.5 months, interpersonal relations including eye to eye contact and verbal communication improved. At 5.5 months the boy was capable of playing and sharing toys with his sibling and other children, behavior noted to be closer to that of an unaffected child. In addition, the decreased frequency of postprandial vomiting led to a significant increment in body weight, body height (from below the third percentile to the tenth percentile) and vitality after 11 months on the diet.

I don’t know about you, but that is pretty impressive improvement for a child {and his parents} who was barely functioning prior to this change in diet.

Another thing I would like to say about diet, is that there are many foods which can trigger or exacerbate asthma, eczema or allergy flares. If your child struggles with any one of these problems, it is important to pay attention to what foods your child is eating prior to symptom flare and which foods seem to make it worse. If this is too difficult, you can perform food allergy and sensitivity testing.

Chronic Infections

When I see kiddos in my clinic with behavioral concerns, I see similar health history patterns. These kids usually have had chronic ear infections treated with antibiotics, strep throat infections, some have eczema or asthma and the vast majority of them either suffer from diarrhea or constipation. When we perform comprehensive stool testing, we find their intestines are chronically inflamed, they have overgrowth of multiple dysbiotic or “bad” bacteria, some have “candida” or yeast overgrowth and the majority of them have parasites. When we begin to treat the intestinal inflammation, remove the overgrowth of “bad” bacteria/parasites/yeast, replace it with healthy bacterial flora, we begin to see huge improvement in behavior, attentiveness, sleep, constipation/diarrhea and sensory issues. Fascinating research is being published on a weekly basis about the gut microbiome as it relates to brain function and chronic disease.

Environmental Toxicities

This is a HUGE problem in the children I see who have developmental and/or behavioral disorders. We are being exposed to countless chemicals in our everyday products and they are damaging our health. The Environmental Working Group collected umbilical cord blood from 10 newborns in 2011 and found 287 toxic chemicals present. Two hundred and twelve of these chemicals had actually been banned 30 years prior. Many of these chemicals cause cancer, birth defects, hormone disruption, immune system dysfunction and are known neurotoxins. When our children are being exposed to so many chemicals on a daily basis, it is no surprise to me that behavioral and developmental disorders are on the rise. In my clinical practice, I see a major correlation between environmental toxicites and speech/developmental delay in children as well as sensory processing difficulties {more info on SPD in this post}. When we can support our children’s bodies and assist them in removing toxic chemicals that are bound in the tissues, not only do they feel and perform better, but we are improving their overall health and reducing the risk of serious diseases.


Hagberg, H., et al.,, “Clinical Symptoms and IgE Responses to Common Food Proteins and Inhalants in the first 7 Years of Life,” Clin Allergy, 1987; 17: 571-78.

Mitchell, E., “The Childhood Food Allergy Mystery,” Newsday, Feb. 21, 2006.

Montague, T., “Environmental Toxicants and Developmental Disabilities,” Rachel’s Environmental Health & News, Jul. 7, 2005; 821

Perry, V. H., “The Influence of Systemic Inflammation on Inflammation in the Brain: Implications for Chronic Neurodegenerative disease,” Brain Behav Immun, 2004; 18: 407-13.

Romagnani, D.S., et al., “Regulatory T-Cells: Which Role in the Pathogenesis and Treatment of Allergic Disorders?” Allergy, 2006; 61: 3-14.

Sarah Campbell