How Your Toddlers Immune System Works And Develops

Dr Ziad El Hachem: General Pediatrician, Pediatric Infectious Diseases, Notre Dame des Secours Hospital, Jbeil – Lebanon

There are more than 1600 genes that are associated with innate and adaptive immune responses. These genes are critical for continuing life in a threatening climate. However, the insusceptible framework is still in its nascent stage when the child is born and is developed as a result of being exposed to unfamiliar situations and difficulties through their adolescence by means of youthful and mature adulthood (counting pregnancy), to the decay of mature age.

The innate immune system:

The innate immune system provides an early first line of defense against invading pathogens. The cells that are involved are neutrophils, monocytes, macrophages and dendritic cells. These act together with the adaptive immune system. These cells develop and mature sporadically. The capabilities of the innate immunity however is weak in newborns compared with later life.

The adaptive immune system:

The adaptive immune system is acquired and it is composed of specific systemic cells and mechanisms that eliminate the pathogens and prevent their growth and development.

The thymus is where the T cells develop, and it is largest at birth and during the first years of life. Mature single CD4+ and CD8+ positive T cells are detected firstly in the thymus at week 15.

During childhood, the immune system progresses at a very impressive rate. It is important to keep it that way because this determines the future health of the child in the later years. The kid’s immune system continues to develop during the first 6 years of life.

Immune System During toddlerhood (Ages 1–3):

  • Microbiota composition is still developing.
  • NK cells are still developing to reach the adult levels.
  • IgG and IgA are still developing.
  • Th1 mediated immunity is still developing up to 2 years age.
  • T cell independent antibody response is immature until 1 year and then continues to develop from 2 to 5 years age.
  • The continuation of breastfeeding during toddlerhood offers ongoing benefits for building your child’s immunity. In case you can’t breastfeed, your doctor will prescribe for you an adapted fortified formula which will include specific oligosaccharides to support the child immune system, these oligosaccharides are also present in breastmilk.
  • Serving plenty of vegetables and fruits for the toddlers is very important for acquiring all the vitamins needed.
  • Be aware that using antibiotics in unnecessary situations – as is the case with most colds that are caused by viruses – may actually hurt immunity. The frequent and repeated usage of antibiotics can emerge antibiotic-resistant bacteria that become more difficult to treat.

Importance of prebiotics:

The digestive system includes 60 to 70% of the body’s immune cells.
Prebiotics help the good bacteria that is naturally present to thrive. Therefore the healthy level of good bacteria helps to fight the harmful bacteria supporting the kid’s immune system.

When supporting the immune system, prebiotic oligosaccharides help in building stronger immunity therefore reducing many types of infections and fever episodes.

Prebiotics occur naturally in tomatoes, artichokes, onions, garlic, chicory, dandelion greens, asparagus, leeks, berries, bananas, flax seed and legumes.

Prebiotics are also present in specific formula milk in the form of Galacto-oligosaccharides (GOS) and Fructo-oligosaccharides (FOS).

Due to the ongoing development of the immune system in the first three years, it is very crucial to take care of the child’s optimal nutrition through food and milk that give the required proteins, carbohydrates, omega-3, vitamins, zinc, iron and prebiotics in order to secure growth and development, cognitive function and building immunity.

Aptamil is not the author of this article, as it has been written by Dr Ziad El Hachem who is the owner of the content




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