The Top 3 Foods That Cause Poor Gut Health in Kids, From a Nutritionist

When parents feed their children a nutritious diet, they can often underestimate the importance of gut health at such a young age.

"Healthy gut microbiota is crucial for supporting overall well-being and optimal growth," licensed functional nutritionist Kourtney Simmang told Newsweek. "Differences between children and adults in terms of gut health can exist. Children have developing immune and digestive systems, which may make them more susceptible to dietary influences on gut health.

"Additionally, certain foods that can be well-tolerated by adults may cause more pronounced effects on children's digestive systems due to their sensitivity."

A child eating healthily
A stock image of a young girl looking happy while eating healthy food. Two nutritionists have given advice about what foods to avoid to prevent poor gut health in children. oksun70/Getty Images

Good gut health is important regardless of age, but when it comes to children it plays a pivotal role in brain development, immune system and growth. A report published in January 2021 in the Gastroenterology journal by the Department of Pediatrics at the University of Chicago explained that the gut microbiome should be thought of as an organ system that affects childhood development.

The microbiome is a complex network of bacteria, fungi, and viruses, most of which are found in the small and large intestines. As detailed by the Harvard School of Public Health, these elements work together to stimulate the immune system, break down toxic food components and synthesize certain vitamins.

A healthy gut helps to absorb the nutrients that the body needs and breaks down compounds before they're digested. This is why gut health shouldn't be overlooked at any age, and Simmang has shared three types of food that can have negative impacts on children.

Avoid Too Many Processed Foods

It's no secret that processed foods aren't necessarily healthy, but the effect they can have on gut health in children shouldn't be dismissed.

Simmang, the founder of Kale Diagnostics, a holistic medicine practice consisting of a naturopathic physician, dietician, and several nutritional therapy practitioners, has explained the negative effect that these can have.

She said: "Highly processed foods, such as sugary snacks, fast food and packaged snacks, can disrupt gut health in children. These foods are typically low in fiber and high in unhealthy fats, sugar, and artificial additives.

"They can disrupt the balance of beneficial bacteria in the gut, leading to inflammation and digestive issues."

Kourtney Simmang, licensed nutritionist
Kourtney Simmang is a licensed functional nutritionist and the founder of Kale Diagnostics. Simmang has shared three key foods that can lead to poor gut health in children. Kourtney Simmang

Too Much Dairy Can Be Harmful

Many might see dairy snacks as a healthy option as it's a known source of calcium to build strong bones, but too much of a good thing can have undesirable effects.

Simmang explained that children shouldn't consume excessive A1 dairy products because of the potentially harmful protein that's found in cow's milk.

"Some children may be sensitive to A1 beta-casein, a protein found in certain cow's milk products. Consumption of excessive A1 dairy products, such as milk and cheese from conventional cow breeds, can potentially lead to gut inflammation and discomfort in susceptible individuals.

"Choosing A2 dairy products or opting for goat milk, or coconut-based dairy alternatives can be a better option for these children."

Regular milk contains both A1 and A2 beta-casein, whereas A2 milk will only contain the A2 beta-casein, which is generally considered the healthier of the two. It's thought that A1 beta-casein can be potentially harmful, so its consumption should be limited. There is however no definitive research on the effects of beta-casein as study results have been mixed.

The presence of A2 beta-casein can often come down to where the cow originates from. Milk that comes from cows in northern Europe is generally high in A1 beta-casein. Cows that originate in the Channel Islands and southern France often have milk that contains A2 beta-casein.

Avoid Excessive Grain Consumption

While processed foods in excess can indeed have a negative impact, that doesn't mean that everything that's natural will be totally healthy. Simmang also highlighted that too many grains can equally lead to bad gut health.

She said: "While grains can be a part of a healthy diet, excessive consumption of refined grain products, especially those containing gluten, may negatively impact gut health in children.

"Gluten, found in wheat, barley and rye can trigger digestive symptoms and inflammation in individuals with celiac disease or non-celiac gluten sensitivity. Additionally, some children may have difficulty digesting large amounts of grains, leading to digestive discomfort.

"One misconception about gut health in children is that all dairy and grain products are universally beneficial. They can be part of a healthy diet, excessive consumption of A1 dairy products and refined grain products, particularly in sensitive individuals, can potentially impact gut health negatively."

After sharing her advice, Simmang added that these aren't hard and fast rules which will have the same effect on every child as every individual is different. She highlighted that it's about "striking a balance" with the child's needs and a varied diet.

Poor gut health, which Simmang once struggled with herself before discovering functional nutrition, can lead to many complications, from stomach pains, illness or even allergies.

She said: "The effects of poor gut health in children can become expressed in various ways. These include digestive issues like constipation, diarrhea, and bloating, as well as an increased risk of allergies, asthma, and even behavioral problems.

"Consulting with a pediatrician or a registered dietitian can provide personalized guidance and recommendations for maintaining a healthy gut, especially when dealing with specific sensitivities or dietary concerns."

Katie McDonald offers advice for children's diet
Katie McDonald a registered dietitian nutritionist. McDonald has offered advice about what foods parents should favor to better their children's gut health. Katie McDonald

What Should Be Included in a Healthy Child's Diet?

Knowing the foods which should be avoided or restricted, there are some key foods which can help improve it even further.

Katie McDonald, registered dietitian nutritionist, told Newsweek: "Recommendations include adding age-appropriate portions of whole fruits and vegetables to fill about half of your child's plate. With beans, lentils, legumes, low-fat protein choices, and low-fat dairy to fill the other half.

"It's important to assess where you and your child are with nutrition and begin with small, achievable steps, to gradually build better eating habits that can be sustained for a lifetime."

McDonald, of Intermountain Primary Children's Hospital in Salt Lake City, Utah, added that the "biggest misconception" she observes is people "not understanding the connection between food and beverage intake and gut health."

"Many parents are surprised that there might be a dietary link to their child's diarrhea, constipation and abdominal pain."

Is there a health issue that's worrying you? Let us know via health@newsweek.com. We can ask experts for advice, and your story could be featured on Newsweek.

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Newsweek is committed to challenging conventional wisdom and finding connections in the search for common ground.

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