Children with Autism Spectrum Disorder (ASD) often experience gastrointestinal issues – approx. 90% and no one understood why. The gut microbiome plays a huge role in the reason why and the connection between their brain and their gut is another factor. Some of the factors that can impact the gut microbiome are diet, stress, geography, the birthing process, medications, and stress. This can also be applied to those with autism.
What is Gut Microbiome?
The gut microbiome consists of trillions of microorganisms, along with their genetic material. These microorganisms live in our intestinal tract and are responsible for helping to absorb and synthesize nutrients and play an important role in how we digest the food we eat. Also, these gut microbiota play roles in many other functions of the body, including metabolism, immune regulation, cognitive function, and mood.
What is “Healthy Gut”?
Everyone has a fingerprint unique to themselves and everyone has a gut microbiome that is a bacterial fingerprint. Scientists are still researching what a healthy gut microbiome is, but they have become aware of that it is a safety net of sorts. When we have a healthy gut, it keeps things that don’t belong in the bloodstream out, such as undigested food particles, toxins, and microbiota. A healthy gut also helps to fight off infection.
What scientists do know is the diversity of bacteria in the gut is good. This allows different types of good bacteria can help to fight off bad bacteria:
- Good bacteria – also known as beneficial bacteria, is any bacteria that enhance overall health. Probiotics are an example of good bacteria
- Bad bacteria – are harmful to our body and usually cause us to be sick. Some bad bacteria can spoil your food or create an unhygienic environment.
However, as with many health functions, balance is key, having about 85% good bacteria and 15% bad bacteria is a good balance for our gut microbiome. Bacteria are needed to break down carbohydrates or sugars, toxins, and help our body absorb fatty acids so our cells can grow.
The Link Between Gut Bacteria and Autism
According to research, children with autism have reduced gut microbiome diversity, which means they have “fewer kinds of intestinal bacteria” than children without autism. Children with autism often have gastrointestinal issues including constipation, diarrhea, flatulence, gassiness, and abdominal pain at the range of 23% to 70%. Some research has indicated higher percentages – up to 90%. These gastrointestinal problems affect their daily life and their families live and nobody understood why.
Research shows that children with ASD have significantly higher numbers of:
- Bacteroides
- Parabacteroides
- Faecalibacterium
- Clostridium
- Phascolarctobacterium.
They also found these in lower numbers:
- Coprococcus
- Bifidobacterium.
The Gut-Brain Connection in Autism
A study reveals a gene mutation in those with autism that affects neuron communication in the brain. This communication is altered in a way that keeps neurons from staying in close contact with one another or “Velcro” of the neurons.
This study also found that the gut mutation affects a range of gastrointestinal functions including:
- gut contractions
- the number of neurons in the small intestine
- the speed that food moves through the small intestine
- responses to a critical neurotransmitter important in autism (well known in the brain but not previously identified to play any major role in the gut).
These genetic mutations occur in both the brain and the gut and it is suspected that it is the main cause of autism. They have found that while they cannot reverse the mutation they can tone down the effects of it.
Gut Microbiome and Autism Symptoms
This imbalance in the gut microbiome can affect a child with autism and play a role in autism symptom development. Gut bacteria may contribute directly to the development of autism-like behaviors. According to The Centers for Disease Control and Prevention (CDC), 1 in 59 children in the U.S. has received a diagnosis of ASD. They also found that it is more common in boys (four times more) and happens across all racial, ethnic, and socioeconomic groups.
Some autism-like behaviors include repetitive behavior, stimming, and social communication and interaction difficulties. There is also a wide range of symptoms, skills, and levels of disability in functioning. Also, they may experience sensory sensitivities. Studies show that a new form of therapy called microbiota transfer therapy has shown to help gastrointestinal issues in children with autism. Researchers Dr. Rosa Krajmalnik-Brown and James Adams ran clinical trials and also found that it is a promising approach for behavioral symptoms of ASD as well.
Diet and Children with Autism Spectrum Disorder
Diet influences environmental factors in the composition of gut microbiota. Children with autism are very often picky eaters that have a low intake of fruits, legumes, nuts, and vegetables, both fiber-rich foods.
There is no recommended diet for children with autism, yet many parents find that removing proteins and putting them on a gluten-free and casein-free – the proteins found in wheat and milk – can alleviate some of the symptoms of gastrointestinal issues. They may also try elimination diets for a month or so to see if there are any allergies to gluten, casein, eggs, seafood, fish, tree nuts, peanuts, or soy.
Some children with autism suffer from a seizure disorder and some parents have tried a high-fat, low-carb, ketogenic diet that can relieve symptoms. However, poor weight gain, poor growth, and high cholesterol levels can ensue.
Some kids with ASD may also lack some digestive enzymes that break down carbohydrates or have low stomach acid (HCI) causing:
- Stomach aches and bloating before and/or after meals
- Floating or fatty stool
- GERD (gastroesophageal reflux disease)
- Acid reflux
- Weight loss
- Weight gain
- Fatigue after meals
- Sleep disturbances.
Many children with ASD have a restrictive diet often due to also having Sensory Processing Disorder (SPD) “a condition in which the brain has trouble receiving and responding to information that comes in through the senses”. Since eating is a sensory experience it can become overwhelming for ASD individuals. 70% of parents with a child with autism report problems with food selectivity and limited intake of foods:
- Hearing the crunch of a food
- Smelling the food
- Seeing the colors or shapes
- Feeling textures of foods
- The temperature of the food.
Children with autism often favor foods such as French fries, chips, crackers, candy, pizza, and chicken nuggets. These processed foods can lead to malnourishment.
Foods that may make autism symptoms worse include:
- Casein – Proteins in dairy, when it mixes with stomach acid produces exorphin. This can cause brain fog, spaciness, concentration issues, and inflammation
- Gluten – A mixture of proteins found in grains like wheat, rye, barley can cause inflammation and decreased functioning of the cerebellum
- Sugar – causes inflammation, increases erratic brain cell firing, and is addictive
- Artificial ingredients such as additives, preservatives, dyes, colors, flavorings, and sweeteners can also potentially increase autism symptoms and doctors often recommend elimination diets to see if they are causing issues.
Dietary Supplements and Autism
Many kids with or without ASD tend to be picky eaters that may not eat a balanced diet and supplements can be a great way to ensure they are getting the nutrients they need each day. A multivitamin with minerals is a good start for many kids. Teens can benefit from a good multivitamin as well.
Studies show that children with autism spectrum disorder do not consume enough of:
- Vitamin A
- Vitamin B12
- Vitamin C
- Vitamin D
- Iron
- Zinc
- Calcium
- Folate
- Magnesium
- Omega-3s.
If your child eats a vegan or vegetarian diet they may be lacking B12 since it is only found in animal products and you should consult your pediatrician.
If your child does not eat any fat, fat-soluble vitamins such as vitamins A, E, D and K cannot be absorbed in their bodies and too much can be dangerous. It is always best to consult your child’s pediatrician.
About 50% of children with autism have sleep issues. Many parents give their children melatonin to regulate their sleep-wake cycle and balance their circadian rhythms. Melatonin is the hormone produced in the brain by the pineal gland and happens naturally. Some fish, eggs, nuts, seeds, and bananas contain melatonin and are good before bedtime snacks. Your pediatrician may also suggest taking it in supplement form.
Because so many children with ASD suffer from gastrointestinal issues caused by gut microbiome many pediatricians recommend taking probiotics. Scientists have found that they ease gastrointestinal symptoms as well as autism-like behaviors in mice with the probiotic strain Lactobacillus reuteri.
There is still much research to be done, however, the links found between autism and the gut microbiome are promising and offer some relief to children with gastrointestinal issues and may help with autism-like behaviors as well helping children to have a better quality of life similar to neurotypical children.
