Strengthen Your Child’s Immunity Before School Starts

As parents, we do everything we can to prepare our children for the school year ahead. But sharpened pencils and fresh notebooks can only do so much when viruses circulate. To keep infections from slowing your student down, you need natural ways to bolster their immunity.  

Here, we’ll discuss how to strengthen your child’s immune system through healthy habits and mindful lifestyle choices.  

Setting Kids Up for a Healthy School Year

As kids dive into another school year, taking a proactive approach to their immunity can prevent sick days for your entire household. Read on to learn more about the factors influencing immunity in childhood.  

Understanding How Immunity Develops in Children

To better understand how to build up the immune system in children, let’s go over how immunity develops in early life.  

The immune system can be categorized into two parts: The innate immune system and the adaptive immune system.   

• The innate immune system develops in the womb, so it’s present at birth. It consists of the skin, cornea, and mucous membranes, which form a barrier to protect you against pathogens, including viruses, bacteria, parasites, and malignant cells. 
• The acquired immune system develops over time as your body is exposed to foreign threats, like viruses. In response to a pathogen or vaccine, it produces antibodies that remain in your body and protect you if you reencounter that threat. In other words, the acquired immune system keeps a record of foreign invaders so that it can attack them more effectively in the future.¹ 

Children’s immune systems don’t reach maturity until age seven to eight.² Before this point, kids are especially susceptible to infections.  

Recommended reading: Read up on the science behind the common cold to better understand how viruses can impact your household this cold and flu season.  

Environmental Factors That Weaken Defense

Our immune systems don’t function in a vacuum; Certain environmental factors can impact your family’s immunity, including air pollutants and heavy metals. 

• Air pollutants travel through the air we breathe. This is particularly dangerous for children’s still-developing lungs and immune systems. Air pollution is known to suppress T cells, a type of immune cell that helps ward off infection, and can worsen asthma in children.³

  • Air pollution particles have also been found to accumulate in immune cells in our lymph nodes, where they may dampen immunity over time.⁴ But these effects typically aren’t seen until older age. 

• Heavy metals (including lead, arsenic, and cadmium) can impact immune cell production and may make you more susceptible to recurrent infections.⁵ Heavy metal exposure can come from:

  • Contaminated food or water (like water from older supply systems)
  • Old paint that contains lead
  • Cigarette smoke
  • Certain batteries
  • Pesticides
  • Seafood with high mercury levels

Nutrition and Vitamins That Support Immunity

Let’s face it: Kids can be picky eaters. But their dislikes shouldn’t hold them back from having a healthy immune system. Understanding the nutrients that support immunity can help you adjust your child’s diet to fight infections during the school year and beyond.  

Best Nutrients for Daily Immune Support

Some of the most important minerals and vitamins for the immune system include:⁶ 

• Vitamin C is found in fruits and veggies, especially citrus fruits, peppers, tomatoes, strawberries, broccoli, kiwi, and brussels sprouts. It provides antioxidant, antimicrobial, and antiviral benefits, making it critical for immune function. 
• Vitamin A is essential to the innate immune system, vision, and growth. It’s naturally found in leafy greens, yellow and orange vegetables, tomatoes, dairy products, eggs, fish, and organ meat. Since vitamin A deficiency is rare in the United States, supplementation isn’t usually required. 
• Vitamin D is found in a few foods, including fatty fish, but primarily comes from the sun’s UVB rays. It supports immunity by reducing inflammation, curbing viral replication rates, and boosting T cell activity. An estimated 41.6% of Americans have a vitamin D deficiency, and rates become higher in the fall and winter, when people tend to spend less time in the sun.⁷ 
• Vitamin E supports antibody production, cell membrane integrity, and lymphocyte proliferation—a key component of the immune response. It’s naturally found in leafy greens, nuts, seeds, and vegetable oils.
• Selenium is a mineral found in many foods, including eggs, dairy products, meat, seafood, poultry, Brazil nuts, and various grain products. It supports immune cell function and may help reduce infections.
• Zinc has natural antiviral and anti-inflammatory properties, and zinc deficiency is known to compromise immune function. It’s found in many foods, including whole grains, nuts, beans, dairy products, poultry, beef, pork, crab, lobster, and oysters. 

Food vs. Supplements

Medical professionals overwhelmingly recommend getting nutrients through food over supplements, whenever possible. This is because whole foods deliver a combination of vitamins, minerals, and other nutrients that work together to support your health. Nutrients are also the most effective when they come from food because your body can better absorb them.  

So while immunity supplements may seem like the quickest fix, tweaking your child’s diet to include more immune-boosting nutrients is a superior option. But if you’re unable to make dietary changes, or your child has a legitimate nutritional deficiency, supplements could be the right choice. Just talk to your child’s pediatrician before starting any new supplement to ensure it’s safe for them to take.⁸  

Choosing the Right Products for Your Child

Dietary supplements are regulated by the FDA, but they don’t undergo the same rigorous testing as prescription medications in the United States. This makes it crucial to thoroughly vet supplements before giving them to your child.⁹  

Before purchasing vitamins to build the immune system, look for: 

• Third-party certifications, like an NSF or USP seal: These confirm that the supplement has been tested for contaminants and was manufactured in a facility that adheres to certain safety standards.¹⁰ 
• A straightforward ingredient list: Make sure you can read and fully understand the supplement’s ingredient list. Keep an eye out for added sugars and any artificial ingredients. 
• Allergen-free: Prioritize supplements that are free of allergens like nuts, soy, gluten, and eggs. 

Everyday Practices That Promote Strong Immunity

They may not be as flashy as vitamins that claim to boost the immune system, but high-quality sleep, nutritious meals, and good hygiene are three of the most effective ways to increase the immune system.  

Consistent Routines for Sleep and Meals

• Sleep is fundamental to immunity, as it gives your body a chance to recharge, manage inflammation, and produce infection-fighting immune cells.¹¹ Maintaining a consistent bedtime and wake-up time, plus good sleep hygiene (limited screen time before bed, a comfortable bedroom temperature, etc.) can help your child get high-quality sleep each night. 
• Meals: Even amidst the hustle and bustle of a hectic school year, consistent, nutritious meals will help keep your household healthy. While fast food can be tempting, cooking with whole foods is the best way to ensure your children consume enough nutrients to support their budding immune systems.  

Hygiene Habits That Make a Difference

Teaching children good hygiene can lighten the load on their immune systems and prevent them from bringing a virus home.  

• Hand washing: Instilling the habit of washing hands for at least 20 seconds (or as long as it takes to sing “Happy Birthday”) in these scenarios helps limit the spread of germs:

• After using the bathroom

• After coughing, sneezing, or blowing your nose

• After touching communal surfaces; and before eating.

• When you don’t have access to a sink, hand sanitizer can help eradicate viruses and bacteria lingering on the skin. 
• Covering coughs and sneezes: Teach your child to cover their mouth with the crook of their elbow or shirt sleeve while coughing or sneezing. This prevents potentially-infected droplets from spreading throughout the air and on surfaces.  

Strengthening your child’s immune system is possible with a well-rounded approach, combining the benefits of good nutrition, consistent sleep, and stellar hygiene to combat illness before it strikes.  

Resources

1. The Immune System. Stanford Medicine Children’s Health. 
2. Kloc, M., Ghobrial, R. M., Kuchar, E., Lewicki, S., & Kubiak, J. Z. (2020). Development of child immunity in the context of COVID-19 pandemic. Clinical Immunology (Orlando, Fla.), 217, 108510. 
3. Nadeau K, McDonald-Hyman C, Noth EM, Pratt B, Hammond SK, Balmes J, Tager I. Ambient air pollution impairs regulatory T-cell function in asthma. J Allergy Clin Immunol. 2010 Oct;126(4):845-852.e10.
4. Air pollution particles appear to weaken lung’s immune defenses over time. National Heart, Lung, and Blood Institute. Published November 21, 2022. 
5. Zhang, H., Wang, J., Zhang, K., Shi, J., Gao, Y., Zheng, J., He, J., Zhang, J., Song, Y., Zhang, R., Shi, X., Jin, L., & Li, H. (2024). Association between heavy metals exposure and persistent infections: The mediating role of immune function. Frontiers in Public Health, 12, 1367644. 
6. Dietary Supplements for Immune Function and Infectious Diseases. National Institutes of Health. Published June 27, 2023. 
7. Forrest KY, Stuhldreher WL. Prevalence and correlates of vitamin D deficiency in US adults. Nutr Res. 2011 Jan;31(1):48-54.
8. Get nutrients from food, not supplements -- Harvard Health. Harvard Health. Published June 1, 2015. 
9. Dietary supplements. Food and Drug Administration. Published March 6, 2023. 
10. Supplement and Vitamin Certification. NSF International. 
11. Besedovsky, L., Lange, T., & Born, J. (2011). Sleep and immune function. Pflugers Archiv, 463(1), 121.