Nutrition for the Immune System and Child Growth
By Dr Tanisa Kwanbunbumpen
Proper nutrition is vital for the development of children's immune systems, gut microbiome health, and overall growth and well-being. A well-balanced diet rich in essential nutrients helps prevent malnutrition, supports the maturation of the immune system, reduces susceptibility to infections and chronic diseases, and promotes healthy growth and development in children.
Macronutrients
Macronutrients are the three main categories of nutrients that provide the body with energy: carbohydrates, proteins, and lipids (fats). These macronutrients play a crucial role in supporting the immune system and in the growth and development of children.
Carbohydrates
Carbohydrates are the primary source of energy for the body and can be classified into two main categories: simple carbohydrates (sugars) and complex carbohydrates (starches and fiber). Certain types of complex carbohydrates, such as dietary prebiotics and fiber, provide additional benefits for child growth and development. Dietary prebiotics are non-digestible carbohydrates that serve as food for the beneficial bacteria in the gut, known as the intestinal microbiota. This helps to increase the number and diversity of good gut bacteria, which are essential for maintaining a healthy immune system. Fiber is another type of complex carbohydrate that provides additional benefits for gut health and immune function.
The Institute of Medicine (IOM) recommends an intake of 14 g of fiber per 1,000 kilocalories (kcal) of energy consumed for people over the age of one. This intake helps to ensure that children are consuming enough fiber and prebiotics to support the development of a healthy gut microbiome and immune system.
Proteins
Proteins play a crucial role in the growth and development of children, including the proper functioning of their immune system. Proteins are made up of amino acids—the building blocks of the body's cells, tissues, and organs. Adequate protein intake is particularly important during periods of rapid growth, such as the first years of life and puberty.
Protein-energy malnutrition can have significant impacts on a child's immune system. It can increase susceptibility to infections by affecting the body's ability to mount an immune response against foreign invaders. Protein deficiency can also lead to an impaired gastrointestinal barrier, which can make children more susceptible to intestinal pathogens. This can lead to more harmful bacteria in the intestine.
Food sources of protein are meat, fish, eggs, dairy products, and nuts. To ensure proper growth and development, as well as a healthy immune system, it is important for children to consume an appropriate amount of protein based on their age and sex.
Lipids
Lipids, also known as fats, provide a concentrated source of energy. Additionally, certain types of lipids, such as omega-3 fatty acids, have anti-inflammatory properties and can help regulate the immune system. The most important omega-3 fatty acid is docosahexaenoic acid (DHA), which is critical for brain and eye development. It is recommended that children consume 100 mg of preformed DHA per day during the first two years of life.
The main dietary sources of DHA are oily fish, such as salmon, mackerel, and sardines, though some fish can be high in mercury and should be limited to one serving per week to avoid poisoning. Other healthy sources of lipids for children include nuts, seeds, avocados, and olive oil, which provide a variety of beneficial fats, including monounsaturated and polyunsaturated fatty acids.
Micronutrients
Micronutrients are essential vitamins and minerals that play a crucial role in supporting a child's immune system and overall health.
Vitamin A: This vitamin helps strengthen the body's natural defenses against infections. Good dietary sources include yellow and orange fruits and vegetables like pumpkin and carrots.
Vitamin B12: This vitamin is important for the immune system's ability to fight off threats. Good sources are meat, fish, eggs, and dairy products. Vegetarian children may need supplements to avoid deficiency.
Vitamin C: This vitamin enhances immune function, antibody production, and the function of the epithelial barrier. It helps prevent the activity of pro-inflammatory cytokines and acts as an antioxidant. Dietary sources of vitamin C include strawberries, kiwi, cantaloupe, and broccoli.
Vitamin D: This vitamin regulates the immune system and has anti-inflammatory effects. Good sources are fatty fish, egg yolks, and fortified foods. Sunlight exposure also helps the body produce vitamin D.
Zinc: Zinc is essential for maintaining a healthy immune system. Zinc deficiency can lead to diarrhea and respiratory infections. Good dietary sources of zinc are red meat, poultry, fish, and eggs, whole grains, legumes, nuts, and seeds.
Selenium: This mineral is required for normal immune function and reducing inflammation. The best sources are organ meats and seafood.
Copper: Copper has antimicrobial properties and helps the body produce specific antibodies. Liver and fish are rich in copper.
By ensuring children get a balanced, nutrient-rich diet with these key vitamins and minerals, parents and caregivers can help shape a robust immune system and promote healthy growth and development in their children.
References
Shils ME, Shike M, Ross AC, Caballero B, Cousins RJ, editors. Modern Nutrition in Health and Disease. 11th edition. Baltimore: Lippincott Williams & Wilkins; 2014.
Verduci E, Köglmeier J. Immunomodulation in Children: The Role of the Diet. J Pediatr Gastroenterol Nutr. 2021 Sep 1;73(3):293-298. doi: 10.1097/MPG.0000000000003152. [Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9770123/]
Munteanu C, Schwartz B. The relationship between nutrition and the immune system. Front Nutr. 2022 Dec 8;9:1082500. doi: 10.3389/fnut.2022.1082500.
Cerullo G, et al. The Long History of Vitamin C: From Prevention of the Common Cold to Potential Aid in the Treatment of COVID-19. Front Immunol. 2020 Oct 28;11:574029. doi: 10.3389/fimmu.2020.574029.
Basnet S, Mathisen M, Strand TA. Oral zinc and common childhood infections – an update. J Trace Elem Med Biol. 2015;31:163–166.
Savarino G, Corsello A, Corsello G. Macronutrient balance and micronutrient amounts through growth and development. Ital J Pediatr. 2021 May 8;47(1):101. doi: 10.1186/s13052-021-01061-0. [Available from: https://ijponline.biomedcentral.com/articles/10.1186/s13052-021-01061-0]
How Much Protein Does My Child Need? CHOC Children's. Available from: https://health.choc.org/how-much-protein-does-my-child-need/
Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. Washington, DC: The National Academies Press; 2005.
About the Author
Dr Tanisa Kwanbunbumpen is a pediatric nutritionist at Samitivej Children's Hospital Srinakarin, Bangkok, Thailand. A distinguished graduate of Srinakharinwirot University with First Class Honors, she has further honed her expertise in pediatric nutrition through specialized fellowship training at King Chulalongkorn Memorial Hospital.