In practice, we are seeing more and more kids with high levels of oxalates in the body and the need to be put on a low oxalate diet. This presents often with kids on the spectrum, and is caused by a number of different factors. At Koru Nutrition , we want to help educate you on the basic principles of what oxalates are, and how they can impact our kids with autism.

What are Oxalates?

Oxalate (also called oxalic acid) is a naturally occurring substance found in abundance in plants and humans. The role of oxalates in plants is protective and it’s believed that it acts primarily as an insecticide. Oxalate is not a required nutrient for humans, in fact it is often labeled as an “anti-nutrient”, and too much can lead to kidney stones.

In the gut of a healthy person, oxalate binds with calcium and other minerals and is excreted in the stool before being absorbed. It follows that one of the problems with having too many oxalates is that you run the risk of poor absorption of minerals, in particular, calcium. This can be an issue for growing kids as it can impact quantity and quality of bone growth and density. 

High Oxalate Foods Include: 

It may be surprising that most  high oxalate foods are  foods that most of us consider to be healthy and good for us! And really, these are healthy foods for the average person. But, if someone has problems with processing oxalates and a build-up occurs in the body, then they can be faced with numerous challenges. 

Some foods high in oxalates include:

• Nuts, especially almonds and peanuts
• Most beans
• Beets
• Figs
• Rhubarb, Swiss chard, field greens and spinach
• Amaranth and buckwheat
• Soy
• Sweet potatoes
• Raspberries and blackberries
• Cocoa and dark chocolate
• Tea

This is by no means an exhaustive list, but can provide an idea that basic, everyday, healthy foods may be a problem for our kids with autism.

How can you tell if you, or your child, have high oxalates?

First, you need to determine if you or your child presents with signs of symptoms of high oxalates, which we’ve listed below. Look at the big picture. Does there appear to be consistency within the symptom list below? If so, then you may wish to consider having an organic acid test (OAT) run by a Naturopathic Doctor or other health professional that specializes in autism. 

Symptoms of high oxalates in the body include:

• Headaches, depression, anxiety, brain fog

• Restlessness, moodiness
• Pain (anywhere) – genital, joints, muscles, intestine, eyes
• Cracking in joints
• Low energy and fatigue
• Weakness
• Sleeping challenges
• Burning feet
• Respiratory infections and symptoms
• Gas and bloating
• Bedwetting and incontinence
• Frequent urination
• Urinary pain
• Cloudy urine
• Crystals in urine
• Sandy stools
• Black specs in stools
• Burning in stool
• Yeast overgrowth
• Rashes
• Consuming or craving a high oxalate diet
• Fine or gross motor challenges
• Poor growth in children
• Blood sugar imbalances

Why Does My Child Have High Oxalates?

There are a number of reasons why certain kids (or adults) may have a build-up of oxalates in the body. 

One reason is genetics: Some people are predisposed to high oxalates based on their DNA. So, a diet high in oxalates can contribute to a problem with high oxalates in the body for these individuals.  

Another reason is Vitamin B6 deficiency: B6 is a cofactor for one of the enzymes in the body that helps reduce oxalates (and kidney stones). Additionally, the human body can produce its own oxalate during metabolism, and B6 helps decrease oxalate production.

The last reason we’ll discuss in this post is low levels of beneficial bacteria in the gut: The good bacteria in our gut can help break down oxalates, making it easier to excrete from the body. When the levels of good bacteria in the gut are low (which is frequently the case in kids with autism), higher amounts of oxalate can be absorbed from the digestive system into the body. If your child has been on multiple courses of antibiotics, this can also contribute to high oxalates, as antibiotics are indiscriminate and  will not only kill the target bad bacteria, but also the good bacteria present in the gut. Antibiotics are known to disrupt the gut microbiome, but a specific  bacteria called oxalobacter formigenes, which is a bacteria that specifically helps breakdown and get rid of excess oxalates, is particularly susceptible to antibiotics. 

What Does Oxalates Have To Do With Autism?

Because oxalates in high amounts interfere with certain nutrients and metabolic pathways, it can cause: 

• inflammation;
• leaky gut and yeast overgrowth (candida)
• contribute to nutrient deficiencies with minerals, biotin and glutathione
• can increase histamine (triggering allergic symptoms)
• can contribute to mitochondrial damage (mitochondria are the batteries of our cell so mitochondrial damage contributes to fatigue and weakness)
• seizures
• faulty sulfation (sulfation is an important mode of detoxification in humans)
• oxidative stress and high amounts of free radical damage (oxidative stress is a phenomenon where there is an imbalance in potentially damaging compounds in the body as compared to the protective compounds in the body or the body’s ability to detoxify)

All of the above are potential issues that children on the spectrum may experience. 

So, implementing a low oxalate diet may address many underlying health issues that can be contributing to an autistic child’s symptoms and affecting their quality of life. 

How The Low Oxalate Diet Works?

The low oxalate diet works by reducing oxalates coming into the body from an individual’s diet in order to reduce the total oxalate burden. Further, by reducing the oxalates consumed in the diet, it gives the body more time to release and excrete the stored oxalates in the body as well.

Additionally, implementing a low oxalate diet and incorporating a specific supplement program can help reduce oxalates being generated in the body, balance biochemistry which has been thrown out of whack by the high oxalate levels, and help manage overall symptoms.

How To Implement A Low Oxalate Diet

Warning:  It is important to implement the low oxalate diet slowly. 

Oxalates are often stored up in body tissues. So when you reduce the dietary intake of oxalates, allowing the body a chance to get rid of the stored oxalates, a process called “dumping” can occur. Dumping is when the body’s cells release stored oxalates, which can cause symptoms to get worse, usually occurring in cycles while a person is on a low oxalate diet. To avoid heavy dumping and manage symptom flare ups, it is important to go slow. In fact, done properly, it can take several weeks or months to fully implement the diet.

How Do I Avoid Heavy Oxalate Dumping?

To undertake a low oxalate diet in a way that avoids heavy dumping of stored oxalate, it is recommended to focus on consuming 40-60mg of oxalates in a 2000 calorie diet. In more practical terms, this will mean consuming mostly low oxalate foods with a few medium oxalate foods. 

Specific food preparation techniques can help reduce oxalate content in foods. Specifically, boiling reduces oxalates in beans and vegetables by about 50% (not enough for high oxalate foods) and soaking grains, beans, nuts and seeds will reduce oxalates, but be sure to drain and rinse after soaking. 

We’re here to help!

It can be overwhelming and stressful to undertake a specialized, therapeutic diet; especially if your child is a  picky eater and already has a limited repertoire of foods that they will consume. 

If you or your child would benefit from more support understanding the connection between oxalates and autism, or how to safely implement a low oxalate diet, our clinicians that specialize in autism are ready to help! 

It can be overwhelming and challenging having a child on the Autism Spectrum. As parents it can be hard to see your child struggle with communication and behaviour challenges, difficulties socially interacting with their peers, and/or the ability to concentrate and focus in school. 

Meal times can be especially stressful if your child is picky and refuses to eat; sometimes limiting their foods to just a couple of different items. Then you go and see a health professional, and they may recommend you remove certain triggers, thereby  restricting their food intake even more…aaarrgh!!

So, where do you start? 

First, let’s backtrack a bit and explore what causes Autism…

What Causes Autism?

Autism is a neurological condition where body chemistry influences brain chemistry. Diet and nutrition are the building blocks that affect this biochemistry. 

There is not one single cause of autism. In fact, there are quite a number of different reasons that your child may present with the symptoms or behaviours that they do. 

Autistic people have a higher likelihood of having problems with detoxification in relation to environmental pollutants; artificial colourings, flavourings, and other additives in foods (which are so common in a North American diet); and/or a decreased ability to detoxify the body of these. This can be due to a compromised immune system from gut inflammation, food allergies and intolerances, invading gut pathogens, microflora imbalances, or digestive issues such as “leaky gut”. This could also be due to oxidative stress, or differences in certain chemical pathways in the body, such as methylation and sulfation. 

The above potential variance in detoxification and metabolism in people with autism are just the tip of the iceberg when it comes to innate biochemical differences that may be present. That is one reason why having a key focus on determining which underlying cause or causes (as often it can be more than one) there are for your child’s symptoms and behaviours.

So, where to begin?

Often, the first step is to determine underlying triggers, which may mean having blood work or other laboratory testing completed by a health professional that is specialized in autism.

Laboratory testing done by an autism specialist, such as an experienced Naturopathic Doctor, can provide valuable information including identifying nutrient deficiencies, food allergies and intolerances, gut issues, microbiome imbalances, immune problems and biological differences with certain biochemical pathways. 

As Nutritionists we can then help create strategies for your day-to-day life, in a hands-on way, that assist in the implementation of recommendations made by your Naturopathic Doctor or Functional Medicine Practitioner after testing. We have experience collaborating with other specialists to support the overall treatment plan required. Of course, we’re happy to offer our food or nutrient specific expertise as well!

What happens after lab tests have identified underlying issue(s)?

There are many potential options that would be evaluated on an individual basis including:

• Supplement recommendations, as nutrient deficiencies are common due to several factors including poor diets (from being picky eaters) and imbalanced digestive systems affecting the ability to break down and absorb food. 
• A specialized diet may be recommended for your child. Making dietary changes can promote systemic healing and help improve mood, learning and behaviour. We recognize that dietary changes in itself come with their own set of challenges.

Autism and Special Diets

Gluten and Dairy Free Diets

There is an abundance of diets that have been shown to help children with Autism. The most common and ideal starting point is going gluten and dairy free, as so many children on the spectrum are often sensitive to the proteins gluten and casein. 

In fact, a AIR Survey of parent ratings on treatment success of implementing a gluten and dairy free diet with kids on the spectrum showed that 55% of children experienced improvements on a casein free diet (based on 6950 children), 55% experienced improvements on a wheat free diet (based on 4340 children), and 69% of children experienced improvements on the combined casein and gluten free diet (based on 3593 children). It was also found that children experienced improvements on a casein free diet within a month, and that it took 1-3 months of elimination to see improvements on a gluten free diet. 

Implementing a gluten and dairy free diet can be challenging. But, working with an experienced Nutritionist to help guide you on your child’s journey through these changes can be very helpful. 

Why are gluten and casein so harmful for children with autism?

As mentioned above many children have problems with gluten and casein due to food sensitivities (IgG, IgM, IgA) or food allergies (IgE). They may lack the DPP-IV enzyme (the enzymes that helps to breakdown gluten and casein in the body) or lack digestive abilities to break down the gluten and casein proteins and absorb them. Unfortunately, these proteins can create an opioid-like response in the brain, similar to a drug addiction. If your child craves breads and dairy it may be part of that opioid-like response, where their addiction is so strong they refuse to eat other food groups, resulting in being a very picky eater. 

Gluten can create gastrointestinal inflammation and damage to the intestines resulting in “leaky gut” (or intestinal permeability, if you want to get fancy). Enzymes are diminished and nutrients are not absorbed properly leading to nutrient deficiencies which will affect mood, behaviour and cognition. This process leads to systemic inflammation, which taxes the immune system, and may result in autoimmune responses. Gluten issues and inflammation can cause depression, anxiety, and ADHD symptoms.

It is important to understand that if you implement a gluten-free, casein-free (GF, CF) diet that a child may experience a worsening of symptoms initially, due to the opioid-like withdrawal effect of removing these foods (proteins) from the diet, before they experience improvement.

Food Addictions & Autism

As mentioned above, one of the reasons why so many autistic people are picky eaters is because of food addiction. When the individual gets a “high” from a problematic food (which has shown to be similar to morphine), it can be so strong that they refuse to eat other foods and food groups. This is one reason why you may notice kids on the spectrum gravitating to food such as cheese and bread, but it could be anything. 

Symptoms and signs of a food addiction include:

• Addicted and crave certain foods to the point that they can have temper tantrums if they don’t get it
• High pain tolerance
• Inattention and spacey behaviour
• Aggression (to self and others)
• Stimming
• Mood changes
• Poor eye contact
• Difficulty speaking
• Anxiety, depression and irritability 

Other Special Autism Diets

Although the GF,CF diet is a great starting point, there are many more diets that have been proven to be effective with improving day-to-day life and the health of kids on the spectrum. Based on laboratory test results you might be asked to explore one of the following diets or a combination of them including: 

Specific Carbohydrate Diet (SCD), GAPS Diet, low FODMAP diet, low phenols diet, low oxalate diet, low salicylate diet, ketogenic diet, paleo diet, low carbohydrate diet, candida diet, Failsafe diet, Feingold diet, Body Ecology diet, or a diet to support methylation and sulfation.

Do special diets for autism really work?

It is important to understand the goal of the diet, how to begin, and then progress from there with implementation of the special diet to help ensure the effectiveness of it. And although it might seem intimidating and overwhelming, it can be worth it! 

Based on surveys of parents with children on the spectrum that have implemented a special diet, they have reported the following improvements:

• Gastrointestinal problems relieved
• Diarrhea & constipation lessens/resolves
• Improved language skills and learning
• Greater focus and attention
• Reduced hyperactivity
• Improved eye contact
• More appropriate behaviour
• Aggressive behaviour and tantrums improve
• Better sleeping
• Easier toilet training
• Skin rashes or eczema clear up
• General health & happiness has improved

How to implement a special diet?

We highly recommend being supported by a qualified dietitian or nutritionist with specific experience addressing autism. It is likely they will work together with a Naturopathic Doctor to complete laboratory testing. Having someone to guide the foods to have and avoid in a way that is practical for your family is key. Having someone to turn to for recipes and ideas that are kid friendly, as well as strategies on how to introduce new foods, especially if your child is a picky eater is very important. Having a professional to work with will help take out the guesswork and stress off you to enable a successful outcome for your child. 

Remember you don’t have to do it alone. We know how challenging and overwhelming dietary and lifestyle change can be. But, it’s worth it!