How Nutrition Affects Autism
Autism is part of a set of disorders called Autism Spectrum Disorders (ASD), which is “a developmental disability that can cause significant social, communication and behavioral challenges.There is often nothing about how people with ASD look that sets them apart from other people, but people with ASD may communicate, interact, behave, and learn in ways that are different from most other people. The learning, thinking, and problem-solving abilities of people with ASD can range from gifted to severely challenged. Some people with ASD need a lot of help in their daily lives; others need less.”
The symptoms of ASD vary from mild to severe can include Attention Deficit Disorder (ADD), seizures, anxiety etc.The causes of autism are unclear, but it seems to affect boys 4.5 times more than girls. A combination of environmental, biological and genetic factors seem to be associated with autism. Studies have shown that symptom development and progression is influenced by changes in metabolism and in gastrointestinal function.
Research shows that children with ASD are 4.5 times more likely to complain of GI symptoms, including diarrhea, constipation, abdominal pain, bloating, limited appetite, inflammation, dysbiosis (disruption in microbial balance), poor enzyme production, and low stomach acid. Studies have also shown that there is a greater risk for gluten sensitivity and lactase deficiency with children with ASD.
The GI tract produces 75% of the body’s neurotransmitters and 80% of its serotonin. Additionally, roughly 80% of the immune system originates in the gut. The gut actually has its own nervous system, called the enteric nervous system, which controls the GI tract. The enteric nervous system is independent of the CNS and is responsible for peristalsis and the secretion of enzymes. However, the gut and brain are still connected and send biochemical signals through neurons, the endocrine system, and the immune system. The gut microbiome, which is the microbes that inhabit the GI tract, is involved in how the brain and gut communicate and can alter mood, anxiety, pain and cognition. Balance and diversity of the gut microbiome is imperative for health since the microbes are responsible for immune modulation, vitamin synthesis, production of SCFA, GI detoxification, and many other functions.
The gut also functions as a barrier from the external environment and the body, and it only allows certain particles to pass into the blood stream. Our first line of defense is the Gut Associated Lymphoid Tissue (GALT), which is the mucosal lining consisting of lymphocytes and other immune supporting cells. The intestinal wall is made up of tight junctions, which allow certain particles to pass through. If the tight junctions open, toxins, undigested food, chemicals and larger food particles may enter the bloodstream and cause an inflammatory response. This is called leaky gut, and it can be caused by stress, NSAIDs, antibiotics, alcohol, toxins, gluten, inflammation, protein malnutrition, and dysbiosis. Leaky gut can also result from candida, which is an overgrowth of yeast caused by antibiotics, toxicity, immune deficiency, etc. When the overgrowth reaches a certain threshold, it causes leaky gut and the yeast enters the blood stream and can cause muscle aches, fatigue, ADHD, sore and stiff joints, and other issues.
The leaky gut triggers an immune response and increases cytokine production, which are small proteins that effect other cells. These cytokines break down the blood brain barrier, which allows changes to neurotransmitters, synapse changes and ultimately mood and behavior changes. Many studies have shown that children with ASD have increased permeability in their gut compared to controls, especially when on an unrestricted diet. This means they have a more compromised immune system and will probably absorb less vitamins and minerals and have a greater chance of illness.
Dietary changes and supplements may help symptoms related to autism. It would beneficial to place those with ASD on an elimination diet to determine if they are sensitive to gluten or dairy. Additionally, dysbiosis and leaky gut can be healed with proper diet and the elimination of additives and unprocessed foods.
It is important to strive for a diet that is comprised mostly of whole foods instead of processed foods. A processed food has been purposely changed from its natural state through cooking, canning, freezing, packaging, fortifying, preserving, preparing, or adding ingredients.Whole foods are in their natural state with little or no processing or artificial ingredients, and they tend to be high in vitamins, minerals, and fiber. Processed food tends to come in packages and can be high in sugar, calories, unhealthy fats, preservatives, and sodium, and research shows these items are correlated with obesity and chronic disease. Processing can be minimal or extreme, so focus on purchasing foods that have been as minimally processed as possible – like prewashed lettuce or cut up vegetables. A good rule of thumb is if the food label has a long list of ingredients, don’t buy it!
Whole foods are also devoid of food additives. Food additives are chemicals added to processed foods to maintain or improve freshness, improve nutritional value (fortifying), and to change taste, texture, and appearance. Some food additives are food dyes and artificial colors, high fructose corn syrup, artificial flavoring, artificial preservatives, and artificial sweeteners. Many food dyes and colors have been associated with hyperactivity, GI symptoms and skin issues, while some preservatives are linked to headaches and behavioral or mood changes. Sweeteners and high fructose corn syrup also have side effects, such as mood changes, nausea, vomiting, diarrhea, headaches and toxic exposure.
Studies show that repairing the gut can improve behaviors. To improve barrier function, supplements such as magnesium, vitamin A, vitamin D and zinc, and omega-3 fatty acids are recommended. Additionally, a multivitamin, phytonutrients, glutamine, amino acids can improve leaky gut and immune function. Digestive enzymes can help break down food and a probiotic can help restore the microbiome after dysbiosis.
Research has also shown a link between autism an environmental toxins. It seems like people with autism are not as adept at eliminating toxic chemicals from their body. These chemicals can effect brain neurological functioning and the physical and psychosocial environment. Therefore, try to purchase organic foods as much as possible and definitely stay away from the dirty dozen, which are the 12 foods know to be highest in pesticides. These include strawberries, spinach, nectarines, apples, grapes, peaches, cherries, pears, tomatoes, celery, potatoes, and sweet bell peppers.
Additionally, toxins increase oxidative stress in the body, and studies demonstrate increased oxidative stress in autism. Oxidative stress is an imbalance between free radicals and the body’s antioxidant system, which causes a derailment in many body processes. Our cells contain organelles called mitochondria, also known as the powerhouse of the cell, which produce energy in the form of ATP. During the process of creating energy, free radicals (reactive oxygen species ROS) are produced, which is a normal part of energy metabolism. However, ROS can increase through inflammation, toxins in the environment, and infections to a point where the body can no longer manage the oxidative stress. This causes damage to cell structures, cell death, mitochondrial dysfunction, and issues with important biochemical processes. Additionally, the blood brain barrier is also sensitive to oxidative damage.
Research show that those with ASD have lower levels of antioxidant enzymes and glutathione. Glutathione is the body’s main antioxidant and is responsible for free radical scavenging and getting rid of metals and pesticides. When there is high levels of oxidative stress, glutathione is depleted so free radicals and toxins are not eliminated and detoxification is impaired. Studies show decreased levels of glutathione in ASD patients. If glutathione is decreased, it is imperative to remove environmental toxins and improve detox pathways, otherwise the oxidative load further increases, glutathione continues to decrease and there are increased metabolic, neurological and immunological dysfunction. Eat a rainbow of colors of fruits and vegetables to increase the antioxidant levels in the body. Additionally, supplements can be taken to improve detoxification pathways. Some important nutrients from detoxification are riboflavin, niacin, B6, folic acid, B12, glutathione, BCAA, flavonoids, phospholipids, glycine, taurine, glutamine, NAC, methionine, selenium, zinc, and coq10.
In addition to supplements to repair the gut, alternative therapies can also be used to treat anxiety, depression and ADD. Vitamin C, carnosine, and carnitine have been shown to improve autistic behaviors while magnesium, vitamin B6, inositol, GABA, 5HTP, tyrosine,and phosphorylated serine have been shown to alleviate anxiety. Additionally, some herbs such as valerian, passionflower, lemon balm and theanine can have calming affects.Every child or adult with autism is unique, so different therapies and programs will be appropriate for different people.
By Denise Groothuis MS RD CFMP
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