What Affects Gut Health?
How Dairy, Gluten, and Environmental Factors Affect Gut Health in Pediatric Cancer Patients
The human body is an engineering marvel, with the gastrointestinal tract, or gut, at the heart of many vital processes, especially in children undergoing cancer treatment. A well-functioning gut is key to immune health, digestion, and recovery, but it can be disrupted by dairy, gluten, and environmental toxins. These factors can negatively impact gut health, making it harder for pediatric cancer patients to heal and respond to treatments. Understanding the connection between gut health and cancer recovery can shed light on why careful attention to diet and environmental exposures is crucial in supporting children through their cancer journey. Let’s explore the gut’s intricate role in healing and how to nurture it during the most critical times.
Anatomy of the Gut and Gut Microbiome
The gut is more than just the stomach—it’s an entire system that starts at the mouth and includes the esophagus, stomach, intestines, and colon. Within this system lives a complex community, the gut microbiome, comprised of around 100 trillion microbial cells, including viruses, bacteria, fungi, and parasites. These microbes aren’t just passengers; they play a vital role in maintaining our health by breaking down food, supporting the immune system, and communicating with other organs. Most work harmoniously with our bodies, forming a partnership essential for overall well-being.
“We provide them with food and shelter, and they provide important services for our bodies. These helpful microbes also help to keep potentially harmful ones in check”. (Professional, 2024)
The walls of both the small and large intestine contain four layers:
- Serosa. The thin, outermost layer is made of connective tissue and skin cells.
- Muscularis. Two layers of smooth muscle, one arranged as long fibers and the other as circular fibers.
- Submucosa. A connective layer that includes blood and lymphatic vessels.
- Mucosa. The innermost layer, fingerlike projections increase the surface area for absorption and digestion and secrete mucus that protects the intestine from acid and enzymes. (Tortora & Nielsen, 2020, pp. 670–677)
The microscopic cells of the microbiome reside in the mucosal layer of the intestinal walls and float in the 21 feet of the small intestine and 5 feet of the large intestine that make up our lower digestive tract.
Function of the gut
We think of our intestines as the factory where food is digested and absorbed. Although this is true, there is a world beyond the conveyor belt of food coming in and waste going out.
Seventy percent of our protective immune system cells and antibodies, 500 different species of bacteria, and half of all the nerve cells in our body live in our gut. The nerve cells in our bowels outnumber those in our spine. All these microscopic cells live in harmony with us and carry out innumerable functions. The gut has been called our “second brain,” a term coined by Dr. Michael Gershon, a neuroscientist working with the enteric (small intestinal) nervous system. (Swift & Mullin, 2011, pp. 22–23)
The brain in our guts can manage digestive functions separately from the brain in our skulls. Even though the two brains can work independently, they are also in constant communication via the vagus nerve.
Through this gut-brain communication, gut irritation is thought to trigger mood changes in the central nervous system. Signals from the gut-brain may also affect thinking skills, memory, and metabolism.
Functions of the gut microbiome
The gut microbiome does many things for our bodies, including:
- Helping to maintain the intestinal walls: Bacteria in the gut produce short-chain fatty acids (essential in immune and anti-inflammatory function) as a byproduct of digestion. Short-chain fatty acids help maintain the gut barrier, preventing bacteria and bacterial toxins from escaping into the bloodstream.
- Manufacturing vitamins: The gut manufactures vitamins, including B1, B9, B12, and K.
- Recycling Bile: Bile is broken down in the gut so it can be reabsorbed and recycled in the liver.
- Influencing mood: Neurotransmitters are produced or stimulated and travel to the brain to affect mood.
- Regulating hunger and satiety: Hormones are secreted to regulate blood sugar, hunger, and feeling full.
What can damage the gut?
Numerous factors can harm our gut, including lifestyle choices, environment, and diet.
Lifestyle
- Chronic stress can trigger inflammation of the inner lining of the colon.
- A high-fat diet can disrupt the bacteria, which can cause fatigue, anxiety, and digestive stress.
Environmental Factors
- Antimicrobials (given to animals we eat or prescribed for human illness)
- Pollution. Chemicals in the air, water, and soil can disrupt the gut microbiome
Diet
The foods we eat can positively or negatively impact gut health.
- Artificial sweeteners can increase the risk of developing chronic inflammation.
- Dairy can cause inflammation and digestive discomfort.
- Gluten, a protein found in many grains, can cause inflammation or damage in the intestines.
Dairy
Dairy consumption can affect the gastrointestinal, respiratory, and skin systems, causing symptoms such as bloating, abdominal pain, gas, diarrhea, constipation, nausea, vomiting, occasional blood in the stool, eczema, hives, nasal congestion, or asthma.
What are the substances in dairy products that cause these symptoms?
Contaminants
- Artificial growth hormones are given to cows to prolong milk production. The hormones enter the milk supply and can lead to obesity in those who consume dairy products. The introduction of artificial growth hormones also increases the incidence of mastitis in cows.
- Antibiotics are given to treat chronic mastitis (see above). Overuse of antibiotics in livestock and humans kills beneficial bacteria in the gut. This can lead to antibiotic resistance and chronic gut problems due to decreased bacterial diversity in the gut microbiome.
- Toxins, pesticides, polychlorinated biphenyls (PCBs), and dioxins pass to humans through dairy products. These chemicals build up in our bodies over time and can harm the immune, reproductive, and nervous systems.
Casein
- Casein is the main protein in dairy products. It can cause allergic reactions and gastrointestinal inflammation.
- Casein breaks down into chemicals called casomorphins, which are like opioids and are associated with behavioral and autoimmune problems.
- Casomorphins cause addiction to dairy products.
Gluten
Here’s why gluten may negatively impact a child undergoing cancer treatments
- Inflammation and Gut Health: Cancer treatments like chemotherapy and radiation can already cause inflammation and damage to the gastrointestinal (GI) tract. Gluten can exacerbate this inflammation, leading to further gut irritation, bloating, and discomfort. A compromised gut can make it harder for the child’s body to absorb nutrients, which are crucial for healing and recovery.
- Immune System Overload: Gluten can trigger an immune response, weakening an already compromised immune system. This added strain on the immune system may make it harder for the body to fight cancer and recover from treatments. For children undergoing chemotherapy, a treatment that heavily impacts the immune system, this can be particularly harmful.
- Nutritional Absorption: Damage to the gut lining caused by gluten can impair the absorption of vital nutrients. Malnutrition is a common concern for pediatric cancer patients, and further reducing nutrient absorption can lead to weight loss, weakness, and slower recovery.
- Digestive Discomfort: Cancer treatments can cause nausea, vomiting, and diarrhea, and gluten can worsen these symptoms. Managing these side effects is essential for maintaining quality of life and strength during treatment.
In summary, gluten can contribute to gut inflammation, immune stress, and malnutrition, making it a potential risk during cancer treatments.
What exactly is gluten?
Gluten is a protein found in wheat, barley, and rye. According to Samsel and Seneff, it is estimated that 5% of the population of North America and Europe now have a gluten intolerance severe enough to be classified as an autoimmune disease called Celiac disease (same as celiac sprue). Some of the symptoms include nausea, diarrhea, skin rashes, anemia, and depression.
In his book Brain Maker, David Perlmutter, MD, describes gluten as “among the most inflammatory ingredients of the modern era.” (Loberg et al., 2015, p. 149) He states that even people who don’t know they have a problem with it can suffer lasting effects of the inflammation caused by eating gluten.
Dr. Perlmutter explains that because it is so inflammatory, gluten can damage the intestinal lining and lead to a “leaky gut,” a condition that allows poorly digested food particles and toxic substances into the bloodstream. When this happens, there is a surge in inflammation and irritation of the immune system, which increases the risk of brain ailments, autoimmune diseases, and cancer.
Environmental Factors
An environmental factor that compounds the danger of dietary gluten is that in America, the herbicide glyphosate (the main ingredient in Round Up) is sprayed on many crops to dry them just before harvest. Researchers suspect that glyphosate contributes to obesity, Alzheimer’s disease, Parkinson’s disease, infertility, depression, cancer, and other illnesses. “Glyphosate, patented as an antimicrobial, has been shown to disrupt gut bacteria in animals, killing beneficial forms and causing an overgrowth of pathogens.” (Samsel A, Seneff S., 2013)
Can the Gut Microbiome heal?
The good news is that the gut microbiota can repair itself very rapidly. “The bacteria in the gut divide quickly, capable of doubling in number every thirty to forty minutes”. (Sonnenburg & Sonnenburg, 2016, p. 16)
The goal is to encourage diversity in the gut so that the bacteria that grow and establish themselves are the ones that promote our health. “Each species of microbe within your microbiota has its genetic code. No two gut microbiotas are identical. Therefore, your microbiome is a major contributor to your individuality. You can think of your microbiome as an internal fingerprint of sorts.” (Sonnenburg & Sonnenburg, 2016, pp. 18–20)
Dietary Changes
Dietary changes are the primary way to increase good bacteria and heal our gut microbiomes and ourselves.
Microbes become established according to the food we eat regularly. Most people who follow the Standard American Diet tend to have limited diversity in their microbiomes. This happens largely because they often fill their diet with processed foods, which are typically low in both fiber and essential nutrients. As a result, the lack of these key components leads to a less diverse and less healthy microbiome.
Gut Health: What can you do?
There are some things you can’t control, such as medical therapies deemed necessary by your child’s medical team, but there are things you can do to help your child’s gut.
- Don’t beat yourself up over those impossible-to-control aspects of your child’s illness.
- Don’t be afraid or make fear-based decisions.
- Get excited about nutrition and its power to heal.
- Learn health-promoting habits and be willing to make changes in diet and lifestyle.
- If your infant or toddler is experiencing diarrhea or other gut issues, and you worry about their nutrient intake, try vitamin patches such as PatchAid Kids or PatchMD.
Nutrition and its Power to Heal
- Follow a plant-based, organic diet.
- Learn the foods that act as prebiotics and probiotics (everything the good bacteria love to eat).
- Avoid dairy and gluten.
- Bookmark The Environmental Working Group (EWG.org), as it is a great resource for learning about chemical pollution and how to avoid it as much as possible.
The human gut is a complicated, amazing place. Let yourselves be inspired to learn more about it and its awesome potential to improve the health and well-being of the whole family. Health is pretty essential!
References
Loberg, K., Perlmutter, D., & Perlmutter, D. D. (2015). Brain Maker: The power of gut microbes to heal and protect your brain for life. http://ci.nii.ac.jp/ncid/BB18997387
The Brain-Gut connection. (2024, January 24). Johns Hopkins Medicine. https://www.hopkinsmedicine.org/health/wellness-and-prevention/the-brain-gut-connection
Barnard, N. D., & Burton, D. (2017). The Cheese Trap: How Breaking a Surprising Addiction Will Help You Lose Weight, Gain Energy, and Get Healthy.
Sonnenburg, J., & Sonnenburg, E. (2016). The Good Gut: Taking Control of Your Weight, Your Mood, and Your Long-term Health. Penguin Books.
Samsel A, Seneff S. Glyphosate, pathways to modern diseases II: Celiac sprue and gluten intolerance. Interdiscip Toxicol. 2013 Dec;6(4):159-84. doi: 10.2478/intox-2013-0026. PMID: 24678255; PMCID: PMC3945755.
Professional, C. C. M. (2024b, June 19). Gut microbiome. Cleveland Clinic. https://my.clevelandclinic.org/health/body/25201-gut-microbiome
Physicians Committee for Responsible Medicine. (n.d.). Health concerns about dairy fact sheet. https://www.pcrm.org/node/130516
Swift, K. M., & Mullin, G. E. (2011). The Inside Tract: Your Good Gut Guide to Great Digestive Health. Rodale.
Microbiome. (n.d.). National Institute of Environmental Health Sciences. https://www.niehs.nih.gov/health/topics/science/microbiome
Tortora, G. J., & Nielsen, M. (2020). Principles of Human Anatomy. John Wiley & Sons.

