The document discusses the relationship between autism and nutrition from three perspectives: how nutrition may impact autism development, how food issues can manifest as autism symptoms, and how diet can be used as an autism treatment. It explores various dietary approaches used for autism including gluten-free, probiotic, vitamin/mineral supplementation, and metabolic therapies. While research on nutrition and autism is still emerging, dietary changes may help alleviate gastrointestinal and behavioral problems for some people with autism.

1. Autism and Nutritional
Care
Dr. Yousef Elshrek

2. • Autism, or autism spectrum
disorder (ASD), refers to a broad
range of conditions characterized
by challenges with social skills,
repetitive behaviors, speech and
nonverbal communication.
• According to the Centers for
Disease Control, autism affects an
estimated 1 in 59 children in the
United States today

3. Is There A Link Between Diet/Nutrition/GI
Tract/ Feeding And Autism?
• Researches suggests that food plays a
critical role in the development of autism
and in the escalation of ASD symptoms
• Food-related issues, such as selective
eating and nutritional deficiencies, are
often manifestations of ASD
• Of the dietary therapies have been
proposed to prevent or manage ASD

4. • Within both the research and the clinical communities, the relationship
between autism spectrum disorder (ASD) and diet has long been a topic
of discussion.
• However, understanding the complex relationship between autism and
food continues to be an ongoing challenge.
• This is largely because food can play a role in each of three distinct
areas:
1. the development of autism,
2. the manifestation of symptoms, and
3. the treatment of the condition.
• When considering the relationship between autism and food from each
of these perspectives, it is important to examine the existing research and
what it can mean for the future of autism treatment and prevention.

5. • There is broad consensus within the research community that autism is caused
by a wide range of factors, including both genetic characteristics and
environmental influences.
• Most scientists also agree that the pathogenesis of autism begins during
prenatal development.
• This idea has led some researchers to hypothesize that the mother’s nutritional
status may be among the environmental causes of autism that interact with
genetic factors to cause the development of autism.
• Indeed, multiple studies have established strong correlations between diet-
related health conditions in the mother and a higher risk of autism in the
child.
• For instance, both type 2 diabetes and gestational diabetes have been
associated with a higher risk of autism.
• In addition, if the mother meets the standards for obesity, the risk of autism
increases by 21.5%, and if the mother has hypertension, the risk of autism in
the child rises by 14.3%

6. • In 2017, a researcher at UC Davis published a paper proposing a
mechanism through which a mother’s diet-related health conditions
may facilitate the development of autism.
• Based on a review of the latest research in the field, the researcher
suggested that these conditions were associated with a lower intake
of several key micronutrients that may be involved in the etiology of
autism: zinc, copper, iron, and vitamin B9.
• In combination with genetic risk factors, an insufficient intake of
these nutrients may contribute to disruptions in fetal brain
development that lead to autism.
• Although future research is needed to conclusively establish a
causal relationship between maternal nutritional status and autism, it
is clear that the mother’s relationship with food before and during
pregnancy is directly associated with the development of autism

7. • It is important to note that pregnant mothers who have
one of these food-related health conditions can still
take action to reduce the risk of autism for the child.
• By making strategic dietary decisions that target
specific micronutrients, it may be possible to reduce
autism risk.
• Studies in animal models have also shown that taking
supplements of certain micronutrients can effectively
reduce autism risk.
• In the future, clinical trials in humans may make it
possible to identify the most effective food and
nutritional supplement choices for expectant mothers
who are concerned about autism.

8. • FOOD-RELATED ISSUES AS A MANIFESTATION OF
AUTISM
• While the discussion of food as a potential cause of autism remains
primarily within the research community, many patients and
families experience a more concrete connection between food and
autism on a daily basis.
• Put simply, children with autism are significantly more likely to be
“selective” or “picky” eaters.
• According to one estimate, about 25 percent of healthy children are
picky eaters, while about 80 percent of children with autism
demonstrate selective eating tendencies, often refusing to eat (or
even try) whole categories of foods.
• In the most serious cases, a child with autism may limit their diet to
as few as five foods.

9. • One of the proposed explanations for the increased incidence of selective eating
among patients with autism is their heightened sensory sensitivity.
• According to some estimates, about 90% of children with autism process
tactile, olfactory, visual and auditory information differently than normally
developing children.
• Based on these statistics, it should come as no surprise that preferences
regarding the taste, texture, smell, and even appearance of food are evident in
patients with autism.
• Unsurprisingly, studies also show that selective eating issues in patients with
autism can lead to deficiencies in important micronutrients—especially among
the patients with the most restrictive diets.
• While specific nutritional deficiencies are likely to depend largely on a child’s
individual food restrictions, a broad study of over 250 children with autism
from five different US states highlighted insufficient consumption of vitamin A,
vitamin C, zinc, phosphorus, fiber, choline, calcium, vitamin D, and potassium.

10. • Although the commonness of inadequate intake is just as high among
normally-developing children as patients with autism for some of these
nutrients, the effects on patients with autism may be more significant.
• For instance, evidence suggests that certain nutrients are less readily absorbed
by patients with autism.
• As a result, the problem can escalate from inadequate intake to measurable
nutrient deficiency much more quickly.
• A possible explanation for why certain nutrients are less readily absorbed in
patients with autism is the difference between the gut microbiome in patients
with autism and their healthy counterparts.
• Bacteria in the gut play a key role in nutrient absorption, and studies in both
human and animal models suggest that the bacterial composition of the gut is
different for patients with autism.
• Although there are not yet results from clinical trials, modifying the gut
microbiome in patients with autism to optimize absorption and minimize
gastrointestinal issues is being considered as a potential therapy

11. • FOOD AS A CONTRIBUTOR TO THE ESCALATION OF
AUTISM SYMPTOMS
• For patients with autism, food selectivity can also exacerbate other symptoms.
• Deficiencies in multiple nutrients, including methyl B12, vitamin D, and folic acid,
have all been associated with autism etiology and the core symptoms of the disorder.
• Moreover, it is widely recognized within the research and clinical communities that
the gut microbiome is impacted by food choices—and the health of the gut
microbiome is directly related to both gastrointestinal and neurological symptoms of
autism.
• For instance, disruptions in the gut microbiome can affect gut motility, which is a
common symptom of autism.
• Also, in patients with Leaky Gut syndrome (which is also common among patients
with autism), toxins from the microbiome can enter the bloodstream and impact the
brain, potentially contributing to the neurological symptoms of autism.

12. • Because repetitive behaviors—such as selective eating—are among these
neurological symptoms, abnormal food behaviors in patients autism may
even be driving a vicious cycle: the more a patient restricts nutrients, the
more their internal neurological processes will support a tendency toward
restriction.
• There is also preliminary evidence that consuming certain types of foods
may directly exacerbate symptoms of autism.
• For example, some studies indicate that dietary gluten and casein are not
properly digested in the gut of patients with autism.
• Not only can the resulting peptides interfere with regular bowel motility,
but they can also directly affect brain functioning.
• In patients with “leaky gut”—a condition commonly associated with
autism—partially-digested peptides may cross the intestinal barrier and
build up the brain, where they can have an opioid-like effect that is
associated with some of the core symptoms of autism.

13. • When patients are not getting the nutrition they need from food, another option is to
boost micronutrient intake through supplementation.
• Taking supplements optimized for bioavailability can be a particularly effective
strategy for patients who struggle with the sensory processing of a normal, balanced
diet.
• Although research is still in the early stages, studies on supplements like butyric acid,
methyl B12, and folic acid offer preliminary evidence of behavioral improvements in
patients with autism.
• Clearly, the relationship between autism and food is complicated.
• In pregnant mothers, nutritional status can affect a child’s risk for autism.
• During childhood and beyond, abnormal food behaviors can manifest as a symptom
of autism, and they can exacerbate other symptoms by affecting the patient’s
neurological and gastrointestinal functioning.
• At the same time, the relationship between autism and food presents opportunities
for dietary interventions that may prevent or resolve symptoms of autism.
• This possibility is opening up exciting avenues for research into nutritional
supplementation therapies that could improve the lives of people with autism and
their families.

14. • In general, the causes of autism are currently not known, but significant
numbers of studies are underway with a view to learning how it develops.
• Researchers have identified several genes that appear to have connections
to ASD. Sometimes, these genes arise by spontaneously mutate. In other
cases, people may inherit them.
• In studies of twins, autism often has a strong correlation between twins.
• For example, if one twin has autism, the other is likely to have autism an
estimated 36 to 95 percent of the time, according to the NINDS.
• Those with autism may also undergo changes in key areas of their brains
that impact their speech and behavior.
• Environmental factors might also play a role in the development of ASD,
although doctors have not yet confirmed a link.
• However, researchers do know that some rumored causes, such as
parenting practices, do not cause autism.

15. • AUTISM AND THE GUT
• However, multiple reports describe chronic GI
dysfunctions/symptoms in 9% ‐ 84% of children with
Autism Spectrum Disorders (ASD)
• Constipation
• Diarrhea
• Abdominal bloating, discomfort, irritability
• GI reflux or vomiting
• Pathological findings :
inflammation of the GI tract
abnormalities of the enteric nervous system
compromised gut microflora
• Active research currently on‐going
GI issues
Dietary issues
Feeding issues

16. • AUTISM AND THE GUT
• Rationale for looking for “biomedical”, and
specifically dietary, approaches to treatment
for ASD:
• Other disorders suggest a link between brain
development and function, behavior and diet
• Seizure disorders
• Ketogenic diet used in children with
intractable seizures
• Metabolic disorders
• Phenylketonuria (PKU), galactosemia, etc.
where lack of a specific enzyme causes
significant behavioral and cognitive issues
• Behavioral/cognitive issues treatable with
diet

17. • The Gut Microbiota and Autism Spectrum Disorders
• Gastrointestinal (GI) symptoms are a common comorbidity in
patients with autism spectrum disorder (ASD), but the underlying
mechanisms are unknown.
• Many studies have shown alterations in the composition of the fecal
flora and metabolic products of the gut microbiome in patients with
ASD.
• The gut microbiota influences brain development and behaviors
through the neuroendocrine, neuroimmune and autonomic nervous
systems.
• In addition, an abnormal gut microbiota is associated with several
diseases, such as inflammatory bowel disease (IBD), ASD and mood
disorders

18. FIX YOUR GUT, FIX YOUR BRAIN
• The gut microbiota is believed to play a pivotal role in human
health and disease through involvement in physiological
homoeostasis, immunological development, glutathione
metabolism, amino acid metabolism, etc., which in a reasonable
way explain the role of gut-brain axis in autism.
• Branded as a neurodevelopmental disorder with psychiatric
impairment and often misclassified as a mental disorder, many
experts in the field think that a therapeutic solution to autism is
unlikely to emerge.
• As the pathophysiology is still elusive, taking into account of
the various symptoms that are concurrent in autism is important.

19. • Gastrointestinal problems that are seen associated with most of
the autism cases suggest that it is not just a psychiatric disorder
as many claim but have a physiological base, and alleviating the
gastrointestinal problems could help alleviating the symptoms
by bringing out the much needed overall improvement in the
affected victims.
• A gut disorder akin to Crohn's disease is, sometimes, reported
in autistic children, an extremely painful gastrointestinal disease
which is named as autistic enterocolitis.
• This disturbed situation hypothesized to be initiated by
dysbiosis or microbial imbalance could in turn perturb the
coordination of microbiota-gut-brain axis which is important in
human mental health as goes the popular dictum: "fix your gut,
fix your brain."

20. • FOOD REFUSAL IN ASD
• may be secondary to:
• Obsessions
• Perseverative interests
• Sensitivity to taste and/or smell of food
• Sensitivity to food textures
• Food neophobia (fear of new foods)
• Operant behavior
1. learned aversion
2. punishment e.g. pain

21. DIET “THERAPIES”: RATIONALE
• GI: Immune/Inflammation /Food Sensitivities/Allergies
• Gluten‐free, casein‐free diet (GFCF): undigested peptides from these
proteins cross the intestinal wall (“leaky gut”) and disturb brain
neurotransmission causing, or increasing, behavioral
•symptoms.
• Increases in urinary peptides seen in some children with ASD.
• Probiotics: replace harmful gut flora, possibly resulting from over use of
antibiotics , which may secrete neurological toxins and contribute to the
“leaky gut”.
• Stool samples have shown an excess of “bad” bacteria in some children with
ASD
• Survey of 600 primary care physicians indicated that 19% recommended
probiotics for children with ASD; 59% supported families who wanted to use
them. (Golnik & Ireland, 2009)

22. DIET “THERAPIES”: RATIONALE
• Nutrient Deficiencies
• Vitamin B‐6 (and magnesium):
1. B‐6 plays an important role in neurotransmission
2. Relative B‐6 deficiency due to lack of enzyme needed to convert it to it
active form.
• Magnesium given to prevent B‐6‐induced Mg deficiency
• Omega ‐3 fatty acids: essential fatty acids necessary for brain development
1. Low blood levels in some children with ASD
2. Oral supplementation used by ¼ families (Geraghty, 2009)
Reported improvements in behavior following a well designed pilot trial
(Amminger et al, 2007)

23. DIET “THERAPIES”: RATIONALE
• Metabolic Abnormalities/Oxidative Stress /Inflammation
• DMG/TMG (di/trimethylglycine):
1. Dimethylglycine and Trimethylglycine (commonly known as DMG and TMG), are
classified as food substances rather than vitamins.
2. They are found in very small amounts in brown rice and liver. The benefits of
taking DMG or TMG range from behavioral changes, reduction of seizures, and
decreased obsessive-compulsive behaviors to improved language.
3. Methyl donors enhance the immune response and neurotransmitter production
• Vitamin B‐12 and folic acid/glutathione
1. Evidence that methylation pathways may be altered, compromising
anti‐oxidant/detoxification capacity.
2. Single‐nucleotide polymorphisms (small differences in genes) related to these
pathways have been identified in children with ASD and their families.

24. WHY DO PARENTS CHOOSE DIETS/SUPPLEMENT
FOR THEIR CHILD?
• Frustration with the limitations of current therapies; hope for a cure or improvement in
behavior
• Comfort in knowing they have done everything possible for their child; wanting to
have some control over the treatment
• Preference for “harmless” treatments vs. drugs
• Dramatic testimonials abound
1. Active promotion at autism conferences attended by parents
2. Websites
• They may give the therapy credit for changes that may have occurred anyway. The
greater the efforts, the more biased they may be towards seeing them “pay off”

25. DEFEAT AUTISM NOW (DAN!)
• Eliminate dairy products
• Eliminate cereal grains
• Eliminate foods with refined sugars
• Supplement the diet with vitamins and minerals
1. Vitamins: C, B‐6, pantothenic acid
2. Minerals: calcium, magnesium
3. DMG
4. Pycnogenol (“natural” anti‐inflammatory)
5. GABA (gamma amino butyric acid) neurotransmitter
inhibitor

26. GLUTEN
FOODS TO CHECK (MAY CONTAIN GLUTEN)
• Soy sauce
• Energy bars
• Imitation bacon
• Marinades
• Herbal & nutritional supplements
• Drugs & OTC medication
• Play-Doh ©
• Imitation seafood/ fish
• Matzo
• Rice mixes
• Sauces
• Soups
• Self-basting turkey
• Bouillon cubes
• Brown rice syrup
• Candy
• Chips/flavored potato chips/seasoned
tortilla chips
• Cold cuts, hot dogs, salami, sausage
• Communion wafers
• French fries
• Gravy
• Vegetables in sauce
• Breading & coating mixes

27. •OATS
• Need to be certified gluten-
free
• Oats do not contain gluten, but
may be contaminated with
wheat during processing
• Celiac.org no longer strictly
limits oats
S Hyman, 2009

28. CHARACTERISTICS OF THE GFCF DIET
CASEIN
• Foods to Avoid
• Dairy (Milk, yogurt, butter, cheese, cream, cream cheese)
casein, caseinate, lactose, whey
• Foods to Check (may contain casein)
1. Baked goods (bread, pastries, pies)
2. Non dairy creamer (will say “milk” in ingredients)
3. Whipped Topping
4. Soy Cheese
5. Candy
6. Sauce (tomato, pesto)
7. Salad dressing
8. Cereals
• Sounds like Dairy/Milk, but does not contain milk, so OK
• Calcium lactate, calcium/sodium stearoyl lactylate, cocoa butter, cream of tartar, lactic acid, sodium lactate

29. POTENTIAL NUTRITIONAL ISSUES
WITH THE (CFCF+)DIET
• Potential nutrition problems with the DAN! Protocol
1. Lack of dairy –
2. Vitamin D at risk as well as calcium (bone density issues).
3. Often a major source of protein for children
4. Lack of grains – B vitamins, iron
5. Lack of refined sugars
6. Vitamin/mineral supplementation may not be appropriate, sufficient or safe (not
regulated)
Children’s multivitamins lack enough calcium and vitamin D
“Gummy” formulations lack iron
• Recommendations for diet may be influenced by profit or ideology (DAN physicians
often sell the products as well)

30. HELPING FAMILIES DECIDE:
THEY SHOULD KNOW THE RISKS/DIFFICULTIES
1. Discuss with parents
2. Safety of the diet: toxicities; potential deficiencies
3. Efficacy of the diet (based on current evidence)
4. Difficult to follow especially when a child eats outside of the house
5. (school, Grandma’s)
6. Further isolates the child from peers
7. Can be more costly then a traditional diet
8. If the child is a “picky eater” or has feeding problems, these may be
complicating factors when introducing a restrictive diet
9. Can lead to nutritional deficiencies ; the more restrictive the diet the
greater the risk.

31. HELPING FAMILIES DECIDE:
PLANNING TO START THE DIET
• Do they have the necessary resources?
1. Financial
2. Time and effort
3. Availability of acceptable foods
• Are there plans to ensure dietary
• compliance(e.g. lists of safefoods?)
1. At home (other family members?)
2. At school
3. At Grandma’s
• Are there sources of support
to begin/maintain the diet?
1. Clinicians
(physicians/nutritionists/die
titians /nurses)
2. Teachers; day caregivers
3. Other parents/parent
groups

32. IMPROVING THE GFCF DIET
• Concern
• Fiber intake
• Calcium, vitamin D intakes
• Iron/zinc intakes
• Intervention
• Increase fruits & vegetables
• Increase nuts, flaxseed meal
• Use fortified dairy alternatives
• Increase use of non‐dairy calcium
sources
• Increase use of meats, beans,
fortified foods

33. Attention-deficit/hyperactivity disorder (ADHD)
Concerta ↓appetite
Strattera ↓appetite, nausea, vomiting,
constipation, diarrhea
Anticonvulsant
Depakote GI irritation, nausea, vomiting,
diarrhea, ↓serum D and calcium
Keppra
Antipsychotic
Zyprexa
Weight gain, ↑appetite
Risperdal
M. Geraghty et al, 2010
POSSIBLE DRUG‐NUTRIENT INTERACTIONS

34. ARE CHILDREN WITH ASD WHAT THEY EAT?
• Summary
• Children with ASD have an increased incidence of:
1. chronic GI problems
2. selective eating behaviors
• In spite of anecdotal reports suggesting that a subgroup of individuals
with ASD responds to dietary intervention, additional data are needed
before health professionals can recommend specific modifications.
• Current research (ATN/AIR‐P) is focusing on the nutritional status of
children with ASD, both on and off restrictive diets.
• Data will be correlated with other measures of physical health (including
sleep issues) as well as behaviors and will shed light on this controversial
subject.

35. •If parents want to try a diet, knowing the difficulties and
risks,
•they should be supported – preferably by a trained
nutritionist/RD.
•Some children may be unable to communicate genuine GI
pain and behaviors may be improved
•Overall diet may be improved – and there is an established
link between optimal nutritional status and behavioral
health
•Placebo effect is reportedly very strong

36. • References
• Bandini LG, Anderson SE, Curtin CE, Cermak S, Evans EW et al. 2010. Food selectivity in children with
autism spectrum disorders and typically developing children. Journal of Pediatrics. 157(2):259-64.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2936505/
• Cermak SA, Curtin C, Bandini LG. 2010. Food selectivity and sensory sensitivity in children with
autism spectrum disorders. Journal of the American Dietetic Association. 110(2):238-46.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3601920/
• Hyman SL, Stewart PA, Schmidt B, Cain U, Lemcke N et al. 2012 Nutrient intake from food in children
with autism. Pediatrics. 130(Suppl 2): S145-53.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4536585/
• Kawicka A, Requlska-Ilow B. 2013. How nutritional status, diet and dietary supplements can affect
autism: A review. Roczniki Panstwowego Zakladu Higieny. 64(1):1-12.
https://www.ncbi.nlm.nih.gov/pubmed/23789306
• Li YJ, Ou JJ, Li YM, Xiang, DX. 2017. Dietary supplement for core symptoms of Autism Spectrum
Disorder: Where are we now and where should we go? Frontiers in Psychiatry. 8: 155.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5572332/
• Nadon G, Feldman DE, Dunn W, Gisel E. 2011. Association of sensory processing and eating problems
in children with autism spectrum disorders. Autism Research and Treatment. 2011:541926.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3420765/
• Nuttall JR. 2017. The plausibility of maternal toxicant exposure and nutritional status as contributing
factors to the risk of autism spectrum disorders. Nutritional Neuroscience. 20(4):209-18.
https://www.ncbi.nlm.nih.gov/pubmed/26613405