On average, kids experience 6 to 8 colds a year, and they're more than twice as likely to develop symptomatic flu compared to those older. While periodic challenges like these are typical and help your child create a healthy immune response, you probably don’t want them picking up every bug and virus out there. Aside from that, healthy immune system function in childhood can safeguard against chronic diseases and autoimmunity in the adult years. So, what can you do to ensure your child is protected?

Unfortunately, there’s no magic bullet, but evidence-based natural solutions that optimize nutritional status and gut health can be extremely impactful. In this article, we’ll cover how you can use natural immune boosters for children, like wholesome food, nutritional supplements, healthy movement, restful sleep, and stress reduction, to keep your child safe during cold and flu season and in the long run. Before getting into the specifics, let’s review some background on how your child’s immune system develops and why gut health is crucial. 

[signup]

Understanding the Child's Immune System 

The immune system exists to protect you from outside invaders (like bacteria, viruses, fungi, and toxins), as well as your rogue cells that could become cancerous. Your child is born with innate immunity, which exists in the skin, the cornea of the eye, and the mucous membrane of the respiratory, gastrointestinal, and genitourinary tracts. The innate immune system is constantly on surveillance for potential invaders and immediately responds when they’re detected, but its protection is limited, especially early in life.

The adaptive immune system kicks in when the innate immune system can’t neutralize a threat. Your child’s adaptive immunity (made up of T cells, B cells, and antibodies) develops over time in response to their exposure to different microbes and their chemicals, as well as vaccinations. This arm of the immune system responds more slowly but can target a specific threat. In addition, the adaptive immune system can remember previous threats and respond more quickly to the next exposure.  

Healthy child immune system development requires repeated exposure to various pathogens, so the innate and adaptive immune systems aren’t mature right out of the gate. This leaves kids at higher risk of infection. Fortunately, if your child develops a strong immune system, they often only experience specific infections once, and then they’re protected. Even when your child has non-symptomatic infections, the immune system is being trained to protect them as they age.

Amazingly, 70-80% of immune cells reside in the gut, mainly in the small intestine. Poor gut health equates to altered immune system function, so helping your child build strong immunity requires a focus on the gut and its inhabitants.  

The Role of Gut Health 

Gut health and a child’s immunity are intimately connected. One of the ways the gut provides immune system protection is via the physical gut barrier, which helps the body discern what should enter the systemic circulation and what should either remain in the gastrointestinal tract or exit the body in the stool. If the gut barrier becomes compromised, leaky gut can occur. Leaky gut contributes to altered immune system function and chronic inflammation. A balanced gut microbiome protects against leaky gut by secreting a layer of mucin to protect the cells of the intestinal barrier, stimulating the secretion of secretory IgA (an antibody that protects against pathogens), and creating short-chain fatty acids (SCFAs), which provide energy to the cells of the intestine. The gut microbiome also competes with pathogenic microbes for resources and produces antimicrobial substances to inhibit pathogen growth.

In addition to maintaining the physical gut barrier, the gut microbiota also helps to shape and regulate immune responses. When pattern recognition receptors (PRRs) detect a potentially harmful microbe in the gut, immune system mediators are released to quell the threat. This response depends on the composition of the gut microbiota, so if an imbalance exists, immune system function is either less robust or overzealous, both undesirable. You can help your child create and maintain a healthy gut microbiome by incorporating probiotics and prebiotics, either from food sources or supplements.

Probiotics for Kids

Probiotics are live microorganisms that benefit the gut and the entire body. They can bolster the intestinal lining by reinforcing tight junctions and creating mucin, and they inhibit pathogens and maintain gut microbiome diversity. In addition, probiotics regulate the secretion of immune mediators and T cells. Here’s a graphic depicting how probiotics function in the gastrointestinal tract:

Probiotic food sources like yogurt, kimchi, sauerkraut, fermented vegetables, natto, and kefir should be offered daily. If you are a picky eater, high-quality probiotic supplements are an option.

Prebiotics for Kids

Prebiotics are the non-digestible, fibrous parts of plant-based foods that fuel gut microbes, allowing them to thrive and function. Gut microbes ferment prebiotics to create SCFAs, which provide energy to the cells of the colon, maintain a healthy mucus layer in the intestine, and modulate immune system function and inflammation. Prebiotic food sources include legumes (beans and lentils), oats, cooked and cooled potatoes, green bananas, asparagus, dandelion greens, onions, leeks, apples, tomatoes, and green beans. Simple ways to incorporate more prebiotic foods include adding uncooked oatmeal, green bananas, and dandelion greens to a smoothie, adding cooked and cooled potatoes, tomatoes, green beans, and onions to a vegetable soup, or serving apple slices with peanut butter. Prebiotics can also be obtained in supplement form, such as inulin, fructooligosaccharides (FOS), and galactooligosaccharides (GOS).

In addition to incorporating probiotics and prebiotics, the overall nutrition plan is crucial for gut health and for providing your child with the nutrients needed for proper immune system function.

Nutritional Foundations for Immune Health 

Your child’s nutritional status has a significant impact on their immune system development and function. While all nutrients are essential, specific immune-boosting nutrients for kids include vitamin C, vitamin D, zinc, and omega-3 fatty acids. 

Vitamin C

Vitamin C is closely tied to immune system function, and those with vitamin C deficiency tend to have higher infection risk and impaired immunity. Vitamin C supports both innate and adaptive immune cell functions, it protects against pathogens on the skin and aids in killing microbes. Supplemental vitamin C has been found to help prevent and treat upper respiratory tract infections. Excellent food sources of vitamin C are bell peppers, citrus fruits, berries, potatoes, tomatoes, broccoli, Brussels sprouts, and kiwi. 

Vitamin D

Vitamin D, also known as the sunshine vitamin, appears to play an important role in modulating innate and adaptive immune responses. People with vitamin D levels below 30 ng/mL may be at higher risk of developing upper respiratory tract infections and the flu. And low vitamin D is associated with the development and progression of autoimmunity. In addition, vitamin D is involved in gut microbiome composition, antimicrobial peptide creation, and gut barrier health.

There are very few good food sources of vitamin D, so safe sun exposure is crucial for obtaining this valuable nutrient. Of course, access to the sun, latitude, skin color, use of sunscreen, and time of year all impact a person’s ability to create vitamin D from the sun. Parents should request that their child’s vitamin D level be tested, and supplementation should be tailored. 

Zinc

Zinc is a trace mineral that assists the immune system in attacking pathogens. Supplemental zinc has been found to reduce the duration and severity of the common cold, especially when initiated close to symptom onset. Zinc is found naturally in oysters, meat, fish, poultry, beans, nuts, whole grains, eggs, and dairy products. And many breakfast cereals are fortified with zinc.

Omega-3 Fatty acids

Omega-3 fatty acids impact gut health and modulate immune system function. Important gut-related actions include the maintenance of diversity, SCFA production, and reducing inflammatory mediators and lipopolysaccharides (LPS). Omega-3s are also incorporated into immune cell membranes and enhance the activity of T cells, B cells, and macrophages to improve the immune response.

The adequate intake (AI) level of omega-3 fatty acids depends on age. Good food sources of omega-3s include salmon, mackerel, herring, trout, sardines, and tuna. If your child isn’t consuming fish a few times per week, supplementing with a high-quality fish oil may be beneficial. If there’s a sensitivity or allergy to fish, algae oil can help meet their need for these essential fats.

Immune-Focused Meal Planning

Besides providing adequate nutrients for growing bodies and proper immune system function, diet is also a significant contributor to gut microbiome composition and gut barrier integrity. The Western diet, high in ultra-processed foods, inflammatory fats, and sugar, disrupts the delicate gut layer and shifts the microbiome toward dysbiosis. Limiting these types of foods and encouraging a variety of plant-based foods like whole grains, legumes, vegetables, and fruits and fermented foods like yogurt, sauerkraut, pickles, and kefir can help your child maintain a diverse, healthy gut microbiome. 

While there’s no perfect diet for boosting the immune system, the Mediterranean diet has all the ingredients to create and maintain a healthy gut, it’s nutrient-dense, and it’s pretty easy for kids to follow. It’s best to introduce your child to a wide variety of wholesome foods once they start eating solid food. Suppose your child is already accustomed to the standard American diet. In that case, it may be best to ease them into a healthier eating style by offering small amounts of new foods at mealtime, getting them involved in family menu planning and meal preparation, and making mealtime fun. 

Importance of Sleep and Physical Activity 

While nutrition and gut-focused strategies are very impactful, your child’s lifestyle also significantly affects how their immune system matures and functions. Restful sleep and physical activity should be prioritized.

Sleep for Child’s Immunity

Adequate sleep quality and quantity help the immune system to mature and function well. Sleep deprivation increases the levels of pro-inflammatory mediators and reduces immune system function. People who are sleep-deprived have less robust responses to vaccines and are at a higher risk of developing the common cold. Improving your child’s sleep requires creating a consistent bedtime routine that allows for the total hours of sleep for their age:

Once your child reaches the toddler stage, it’s essential to create a consistent sleep routine, be firm about bedtime, and educate your child on why sleep is essential. Additional strategies to improve sleep quality include:

• Helping your child get natural light exposure in the morning.
• Sticking with a wholesome diet.
• Ensuring your child is physically active.
• Limiting screen time during the day.
• Avoiding screens before bed.

Physical Activity and Immune Health in Kids

Exercise substantially impacts immune system function. People who exercise moderately tend to have a more robust immune system response. Part of this may be the positive impact exercise exerts on the health of the gut microbiome. Conversely, those who over-exercise can experience immunosuppression and higher infection risk, so finding balance is essential.

Children of all ages should be encouraged to participate in daily movement. Kids ages 3-5 should move frequently throughout the day. 

Kids 6 and older should aim for at least 60 minutes of physical activity daily. This age group can include exercises that increase their heart rate, like running, swimming, and biking; muscle-strengthening exercises like climbing or pushups; and bone-strengthening exercises like jumping and running. Rather than creating a formal exercise plan for younger children, choose fun activities incorporating movement and discuss why moving their bodies helps keep them healthy.

Reducing Stress and Promoting Mental Well-being 

Mental well-being and a child’s immunity are linked. Chronic stress can impair immune system function by impacting the central nervous and neuroendocrine systems. In addition, stress negatively impacts gut health by altering hypothalamus-pituitary-adrenal and microbiome-gut-brain axis function, which can lead to a leaky gut.

Kids can experience stress on numerous fronts, like school, social media, peer pressure, dysfunctional family dynamics, and lack of structure. Practical ways to incorporate stress reduction in children include:

• Reducing stress at home.
• Encouraging physical activity (especially outdoors) and mindfulness meditation.
• Setting boundaries around social media and screen usage.
• Creating a healthy routine overall.

In addition, kids may not always recognize that they’re dealing with stress, so parents and caregivers should remain engaged and speak with their children about their feelings. If you feel your child needs more formal help, acupuncture, biofeedback, and professional counseling are all safe, effective stress management options. 

Practical Tips for Minimizing Infection Risk 

Providing nourishing foods and fostering healthy lifestyle choices lays the foundation for a healthy immune system, but you can also use practical infection prevention in children. Appropriate age-related vaccinations for your child help train the immune system to protect against serious infectious diseases. Additionally, encouraging simple hygiene practices for kids can effectively prevent and spread infections. 

One of the most impactful strategies is to teach your child how and when to wash their hands. Here are the five essential steps to effective handwashing:

1. Turn on the faucet and wet your hands with warm water; turn off the tap and apply soap.
2. Rub your hands together to lather the soap and rub the back of your hands, between your fingers, and under your nails.
3. Hum the "Happy Birthday" song twice while you lather (roughly 20 seconds).
4. Turn on the faucet and rinse your hands under clean, running water.
5. Dry your hands with a clean towel or an air dryer.

Kids should be encouraged to wash their hands when preparing food, before and after eating, before and after sneezing, blowing their nose, or coughing, before and after playing in a group, and after going to the restroom, touching animals, and handling garbage. Other practical tips include teaching your child to cover their mouth when they cough, to avoid touching their mouth and eyes with unclean hands, to avoid sharing utensils, cups, dishes, and toothbrushes, and to avoid close contact with people who are sick.

Child-Friendly Functional Medicine Lab Tests 

Functional medicine labs for children should evaluate gut health, nutrient status, and cytokine imbalances to help practitioners identify specific areas that may need support to optimize immune system function. It's helpful to use non-invasive immune testing in kids and to work with a pediatric functional medicine or nutrition specialist who can correctly interpret test results to personalize dietary, supplement, and lifestyle interventions for your child. 

Comprehensive Stool Analysis

The GI-MAP + Zonulin test by Diagnostic Solutions can detect microbial imbalances and microbes contributing to disease symptoms and provides indicators of digestion, absorption, inflammation, and immune system function. The add-on zonulin feature can help providers understand if a leaky gut is present. 

Cytokine Response Profile

The CytoDx Panel from Diagnostic Solutions evaluates cytokines, which are essential mediators of the immune system. This test can help practitioners assess the immune system's health and detect imbalances that may contribute to altered immune system function.

SIBO Breath Testing

Small intestinal bacterial overgrowth (SIBO), or an imbalance of microbes in the GI tract, is a reasonably common contributor to leaky gut. The Trio-Smart SIBO Breath test by Gemelli Biotech can detect any of the three types of SIBO (hydrogen, methane, and hydrogen sulfide). If SIBO is present, providers can tailor treatments to restore gut microbiome balance.

FInal Thoughts For Boosting Your Child's Immune System Naturally

The immune system develops over time, so kids are at higher risk for infections. Periodic illnesses, like colds, are routine and help your child develop a healthy immune system function as they age. No single diet or supplement can boost your child's immune system. Instead, you can ensure optimal protection by taking a holistic approach to your child's immune health, focusing on wholesome foods, gut health, sleep, physical activity, and mental well-being. Additionally, you may want to consider age-appropriate vaccinations and educating your child on practical ways to prevent infections, like handwashing.