By Sarah Harris

Sarah Harris N.D.

Specialist Naturopath – Holistic Nutritionist – Herbalist – Homoeopath – Remedial Therapist

Is your child returning to childcare, kindergarten or school?

Find out how you can protect your child’s immunity today; reduce the duration and intensity of infections.

A functionally immature immune system that continues to develop throughout infancy and childhood is present at birth in children.

Although the innate and adaptive immune systems are active in infancy, variations exist between children and adults. For instance, decreased Natural Killer (NK) cell counts are typical of early childhood and peak at adult levels at around five years of age.

Immunoglobulin G (IgG) levels reach adult levels by the age of 12 while Immunoglobulin M (IgM) levels reach adult levels by the age of four. Antibody production is also low in early infancy and rises with age.

Gradual contact with a range of infections helps the adaptive immune response to develop immunological memory of the pathogens and provide a more potent immune response during subsequent encounters, providing protection from the condition.

Children are more susceptible to infectious events from pathogenic exposure until immunological memory is developed because of an immature immune system and decreased pre-existing sensitivity to infections.


The following nutrients and herbs can help support healthy immune function;

  • Astragalus has been proven to increase phagocytic macrophage activity as well as humoral and cellular immunity. [1]
  • Olive leaf was shown to have potent anti-inflammatory properties in addition to broad-spectrum antibacterial activity against several viruses, bacteria, yeasts, and fungi. [2] Olive leaf’s antiviral properties have been proven effective against a variety of influenza and para-influenza virus strains, myxoviruses, Herpes simplex types I and II, Herpes zoster, and rhinoviruses. Additionally, olive leaf is a powerful antibacterial agent that can be used to treat a wide range of pathogens, including Salmonella typhi, Vibrio parahaemolyticus, Staphylococcus aureus (including penicillin-resistant strains), Klebsiella pneumonia, and Escherichia coli, which are the main causes of human intestinal and respiratory tract infections. [3]
  • White blood cell (leukocyte) activity, antimicrobial activity, and NK cell activity are all improved by vitamin C (ascorbic acid). It could help lessen the severity of upper respiratory tract infections and the length and intensity of colds. [4] High vitamin C foods include guavas, capsicum, kiwifruit, strawberries, oranges, papayas, broccoli, tomatoes, kale, and snow peas. 
  • Zinc, a key trace mineral that boosts immunity, supports the healing process, and contributes to the antioxidant defence network. [5] In addition to being abundant in red meat and poultry, oysters are the richest source of zinc. Beans, almonds, crab, lobster, whole grains, cereals, and dairy items are additional excellent sources.
  • By encouraging the activity of immune cells, vitamin D improves the immunological response to both viruses and bacteria. [6] Few foods naturally contain vitamin D, though some foods are fortified with it. For most people, the best way to get enough vitamin D is taking a supplement because it is hard to eat enough through food. Safe exposure to sunlight is important. 
  • In order to stimulate the formation of the gastrointestinal microbiota during childhood, probiotic strains were mixed with the prebiotic oligofructose. This increased gastrointestinal mucosal integrity and promoted resilience against infection.
  • Probiotic strains help enhance gut health, improve immunological function, and safeguard the gastrointestinal microbial ecology of young children to eliminate possible infections and promote resilience against infection
  • Children with Blastocysts hominis infection were used in a trial to illustrate the direct pathogen-displacing abilities of SB. The study’s three treatment arms—metronidazole antibiotic usage, SB intervention, and placebo—were demonstrated to be equally effective at killing B. hominis [7].
  • Omega-3 essential fatty acids (EFAs) promote gut barrier integrity, adaptive and acquired immune function, and control of the inflammatory response. [8] EFAs are both found in herring, salmon, sardines, trout and tuna. Eating a variety of fish at least twice a week supplies an adequate amount. Vegetarian forms include seaweed, chia seeds, flaxseeds, walnuts and beans.

A focus on a wholefood Mediterranean diet inclusive of high intake of fruits and vegetables, lean protein, quality essential fatty acids, and wholegrains (limiting starchy grains and vegetables). Current evidence suggests that the Mediterranean diet provides protection against several diseases associated with inflammation and immune activation. [9]

The Mediterranean diet has also been found to improve disease-related fatigue by lowering the inflammatory load and simultaneously balancing gut microbiota. [10]

Therefore, if your child is returning to childcare, kindergarten or school please consider what strategies best suit you and your family to limit the impact of opportunistic infection to ensure the best start to the learning year.

I would love to discuss these strategies with you further to promote your child’s immunity and reduce the duration and intensity of infections.

Yours in good health,



[1] Bone K. Clinical applications of Ayurvedic and Chinese herbs: monographs for the Western herbal practitioner. Warwick: Phytotherapy Press; 1996. p. 13-20.

[2] Braun L, Cohen M. Herbs and natural supplements: an evidence-based guide. 3rd ed. Sydney (AU): Elsevier/Churchill Livingstone; 2010. p. 711-15.

[3] Khan Y, Panchal S, Vyas N, Butani A. Olea europaea: a phyto-pharmacological review. Pharmacog Rev Jan- May, 2007;1(1):114-118.

[4] Douglas RM, Hemilä H, Chalker E, Treacy B. Vitamin C for preventing and treating the common cold. Cochrane Database Syst Rev. 2007 Jul 18;(3):CD000980.

[5] Zago MP, Oteiza PI. The antioxidant properties of zinc: interactions with iron and antioxidants. Free Radic Biol Med 2001;31(2):266-274.

[6] Klotz LO, Kröncke KD, Buchczyk DP, Sies H. Role of copper, zinc, selenium and  tellurium in the cellular defense against oxidative and nitrosative stress. J Nutr. 2003 May;133(5 Suppl 1):1448S-51S. doi: 10.1093/jn/133.5.1448S.

[7] Dinleyici EC, Eren M, Dogan N, Reyhanioglu S, Yargic ZA, Vandenplas Y. Clinical efficacy of Saccharomyces boulardii or metronidazole in symptomatic children with Blastocystis hominis infection. Parasitol Res. 2011 Mar;108(3):541-5. doi: 10.1007/s00436-010-2095-4.

[8] Singer P, Shapiro H, Theilla M, Anbar R, Singer J, Cohen J. Anti-inflammatory properties of omega-3 fatty acids in critical illness: novel mechanisms and an integrative perspective. Intensive Care Med. 2008;34:1580-1592.

[9] Casas R, Sacanella E, Estruch R. The immune protective effect of the Mediterranean diet against chronic low-grade inflammatory diseases. Endocr Metab Immune Disord Drug Targets. 2014;14(4):245-54. doi:10.2174/1871530314666140922153350.

[10] Haß U, Herpich C, Norman K. Anti-inflammatory diets and fatigue. Nutrients. 2019 Sep 30;11(10):2315. doi:10.3390/nu11102315.

Sarah Harris

Specialist Naturopath, Holistic Nutritionist, Herbalist, Homoeopath

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