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Why do kids become picky eaters? Some become so picky, they end up on feeding tubes. They simply won’t eat. And if they do, they may stick to milk, dairy food, formulas based on milk or pea protein (think Pediasure, Boost, Orgain, Muscle Milk, Ripple, Kate Farms), or only eat that “white” diet of cheese, pizza, Goldfish crackers, mac and cheese. Presenting other foods often means big tantrums. They become anemic, constipated, pale, unhappy, hyper. They may have extra challenges like autism or ADHD or anxiety. And, they are picky picky picky.

When I meet super picky eaters – the ones who don’t function well, may be underweight or overweight, constipated, unable to sleep normally, don’t speak or socialize typically, may have volatility or combative or defiant demeanors, or have attention/focus issues, I start where I’ve seen this start in hundreds of cases in my pediatric nutrition practice. On the upside, it’s not complicated. Downside? There may be a strict elimination diet in your future, if this is your kiddo. Back to the good news: A correctly implemented elimination diet can bust the picky eating – and improve a lot of other problems too.

What’s happening here is this: Leaky gut + wheat or dairy proteins = opiates. Picky eaters are – quite often – addicted to the opiate-like compounds that form from wheat and dairy proteins. If a child has a leaky gut, this will happen, and while other factors and scenarios can worsen the picture, this addicting opioid effect is often the node of trouble that arrests all progress. I have witnessed even feeding therapy and tube feedings strategies fail, when this is overlooked.

The opiate-like compound that can occur from milk is casomorphin. From wheat, it’s gliadorphin. Notice that these sound like “morphine” – as they should, because the are actually opiate-like, based on the receptors in the brain that they adhere to. Similar compounds have been found to form from soy protein, pea protein and whey protein also. These were first described in 1979. Casomorphins and gliadorphins are naturally occurring compounds derived from the digestion of dairy and wheat proteins. They can have opioid-like effects on the brain. Here’s how they can contribute to picky eating in children:

  1. Casomorphins:
    • Source: Casomorphins are derived from the digestion of casein, a protein found in milk and dairy products.
    • Opioid-like effects: When casein is broken down during digestion, it produces peptides called casomorphins. These peptides can bind to opioid receptors in the brain, leading to a range of effects including feelings of relaxation and pleasure. In older kids, more volatility, inattention, and combative behavior may occur. Sleep cycles may be disrupted too.
    • Preference for dairy products: In kids with a leaky gut scenario, eating dairy products can lead to the release of casomorphins, which can make children more inclined to choose dairy-based options – leading to a preference for them over other types of foods.
  2. Gliadorphins:
    • Source: Gliadorphins are derived from the digestion of gluten, a protein found in wheat, barley, and rye. Gluten is also in oats that are not certified gluten free, and in many processed foods as a flavoring or thickener.
    • Opioid-like effects: Similar to casomorphins, when gluten is digested, it produces peptides known as gliadorphins. A healthy non-leaky gut finishes this to individual amino acids, so there is little gliadorphin left to absorb. These peptides can also bind to opioid receptors in the brain, affecting mood and behavior similarly to how casomorphin does.
    • Preference for gluten-containing foods: Eating gluten may lead to the release of gliadorphins. This could contribute to a preference for gluten-rich foods and potentially make children more resistant to trying non-gluten options.

Impact on Picky Eating:

  1. Reinforcement of Preferences: Eating a steady, narrow diet of wheat and dairy foods in the context of leaky gut will lavish the addictive effects of casomorphins or gliadorphins on a child. This will reinforce their preference for these foods, making them less willing to try new or different foods.
  2. Sensory Preferences: Casomorphins and gliadorphins can alter the sensory experience of eating. Children may become accustomed to the specific textures and flavors associated with dairy or gluten-containing foods, which can make them more resistant to trying foods with different textures or tastes.
  3. Withdrawal Symptoms: When kids release of casomorphins or gliadorphins from the food they eat, once these foods are removed, they can actually experience withdrawal – with irritability, tantrums, and foul mood. They may campaign harder to wait it out for those foods. I have seen uncanny abilities in kids to sniff out foods with even trace amounts of gluten or casein in them, so they can keep getting that little bit of opiate like effect. This can further reinforce their picky eating habits.
  4. Constipation: Like any opiate narcotic, casomorphin and gliadorphin can slow gut motility down and cause constipation. They can also dull sensation for stooling, making it hard for kids to potty train and sense when to go.

The cool part of the story is that this opioid effect from casein is genius for newborns and babies. Since the baby’s gut wall is more permeable at birth, ample casomorphins can be had from breast milk or milk based formula. Great! Babies are happy, they can sleep a lot, and this may also help neurons in the brain grow quickly.

But once a child reaches age 18-24 months, the gut is working toward sealing itself to function as a more discerning interface with the outside world. That means casein (and gluten too) should be more completely digested, and absorbed as individual amino acids, rather than large peptide chunks that look like an opiate molecule. Besides slow or arrested language development, a constipated stool pattern, picky eating, some sensory dysregulation, and some beyond-fierce tantrums when favorite foods aren’t presented, another sign that opiate-like peptides may be affecting the brain is head circumference. The baby’s head may grow, grow and keep growing at the top of the chart, even outpacing the child’s velocity for weight and height.

This is where picky eating can become a more serious problem. It may alter brain structure and function – permanently, if not redirected. There is evidence that diet sourced opiate like peptides change how neurons grow, and how they undergo a process called pruning. Pruning is a process that is essential to normal development and learning. The first phase of neuronal pruning begins shortly after birth and continues into adolescence. During this period, the brain produces an overabundance of synaptic connections. These early connections are initially important for basic functions, but not all of them are necessary for long-term functioning. As a child interacts with their environment, learns new skills, and experiences different stimuli, certain synapses are strengthened through a process known as synaptic potentiation, while others are gradually eliminated through synaptic pruning. This helps to refine and optimize the neural circuits, making them more efficient and specialized.

A second phase of pruning occurs during adolescence and early adulthood. This period is characterized by significant changes in brain structure and function. It is believed that this phase of pruning is associated with the maturation of higher cognitive functions, such as abstract thinking, complex problem-solving, and emotional regulation.

Diet sourced opiate peptides may interfere with the pruning process. Here’s how:

  • Altered Neurotransmitter Levels: Opioid peptides may influence the levels of neurotransmitters involved in neuronal pruning. This could disrupt the signaling pathways responsible for initiating and carrying out the pruning process.
  • Disrupted Synaptic Plasticity: Opioid peptides can affect synaptic plasticity, which is closely tied to processes like neuronal pruning. If the normal balance of excitatory and inhibitory signals in the brain is disrupted by opioid peptide activity, it may interfere with the timing and precision of synaptic pruning.
  • Influence on Neurotrophic Factors: Opioid peptides may also indirectly impact the release or effectiveness of neurotrophic factors, which are molecules that support neuronal survival and development. Changes in the availability or activity of these factors could potentially affect neuronal pruning.

If picky eating is present with developmental delays, and especially with diagnoses of autism, ADHD, or conduct disorders, an elimination diet has potential to turn the tide. I have many clinical anecdotes from families seeing a whole new child emerge once the haze and confusion of opiate like chemistry is peeled away. The most common phrase I hear is “the fog lifted”. I also often hear of abrupt positive changes in children trying new foods and textures, learning to sleep, being more calm and having more self regulation, reduced texture sensitivities, and becoming more capable with peers or at school.

While an elimination diet has great potential, it is challenging, and it is paramount that even more nutritious foods are given in place of the foods withdrawn. For a detailed how-to on making this option work, see my e book on Milk Addicted Kids.The main caveat is this: All gluten, dairy, soy, pea protein concentrates and whey protein must be completely and strictly eliminated for a 4-6 month period before evaluating the diet’s efficacy. Learn why, and how to do this, in my e book. Contact me here if you have more questions, and thanks for stopping by!

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