What is immunity?

What is Immunity?

Jan 01, 2021

If there was one buzzword for 2020, it would probably be immunity. We all want a strong immune system, but have you ever stopped to think what your immune system really is? In order to support something, it is important to understand what it is and how it works. So, we sat down with our education team at Jamieson to learn the ins and outs of what makes up immunity.

Let's understand the immune system’s role.1,2
The immune system protects the body against disease or other potentially damaging foreign bodies. When functioning properly, the immune system identifies and attacks a variety of threats, including viruses, bacteria and parasites, while distinguishing them from the body's own healthy tissue. So essentially the immune system is your very own body-guard ;)

With such an important role, it is no wonder that the immune system is made up of an elaborate integrative network, with all components working together to keep you healthy. The immune system is made up of a group of cells and molecules that protect us from disease by monitoring our body and responding to any foreign (non-self) substances they perceive as threats, particularly infectious microbes3.

Our immune system has co-evolved along with a diverse gut flora, not only to create defenses against pathogens, but also to develop tolerance for beneficial microbes3. 70–80% of the body’s immune cells are found in the gut!4

How does the immune system work?1

Without an immune system, we would have no way to fight harmful things that enter our body from the outside or harmful changes that occur inside our body. The main tasks of the body’s immune system are:

1) To fight disease-like bacteria, viruses causing germs (pathogens), parasites or fungi, and to remove them from the body,

2) To recognize and neutralize harmful substances from the environment, and

3) To fight disease-causing changes in the body, such as cancer cells.

The immune system is divided into two types of coordinated responses5:

  • Innate immunity, and (2) Adaptive immunity.

The innate immune system is our first line of defense. It is the immune system we are born with and provides a general defense against harmful germs and substances.  

The adaptive immune system, also referred to as “acquired” is the part of our immunity that is always learning and expanding to protect us against new pathogens. Since the adaptive immune system is constantly learning and adapting, the body can also fight bacteria or viruses that change over time6.

How to best nourish your immune system7,8,9
Each stage of the immune response requires specific micronutrients, including vitamin C, selenium, and protein (including the amino acid glutamine). Diets that are high in processed foods and that include few fresh foods can have a negative impact on the immune system.

The takeaway here is to support your immune system daily with a whole-foods diet, rich in fresh fruits and vegetables, along with good quality protein sources.  



  • Nicholson L. B. (2016). The immune system. Essays in biochemistry60(3), 275–301. https://doi.org/10.1042/EBC20160017
  • A Brief Overview of the Immune System, Revere Health, 07/18/2017,Accessed Date: 08/25/2020. At https://reverehealth.com/live-better/brief-overview-immune-system/
  • E. Ley, D.A. Peterson, J.I. Gordon, Cell 124 (2006) 837–848.
  • K. Abbas, A.H.H. Lichtman, S. Pillai, Cellular and Molecular Immunology E-Book, Elsevier Health Sciences, 2017.
  • Institute for Quality and Efficiency in Health Care. The innate and adaptive immune systems. Accessed 08/25/2020 At https://www.ncbi.nlm.nih.gov/books/NBK279396/
  • Peter J. Delves , Acquired Immunity, MERCK MANUAL Consumer Version, Accessed 08/25/2020 At https://www.merckmanuals.com/home/immune-disorders/biology-of-the-immune-system/acquired-immunity
  • Kau, A., Ahern, P., Griffin, N. et al. Human nutrition, the gut microbiome and the immune system. Nature 474, 327–336 (2011). https://doi.org/10.1038/nature10213
  • Guillin OM, Vindry C, Ohlmann T, Chavatte L. Selenium, selenoproteins and viral infection. Nutrients. 2019 Sep;11(9):2101.
  • Wessels I, Maywald M, Rink L. Zinc as a gatekeeper of immune function. Nutrients. 2017 Dec;9(12):1286.

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