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What is a Healthy Immune System?

This article is for educational purposes only.  It does not reflect the opinion of Glanbia Performance Nutrition, nor is it intended for product marketing purposes.


The human body has many physical barriers and defense mechanisms to help protect the body, but one system of monumental importance is the immune system. The innate immune system is composed mainly of physical barriers, such as skin and mucous membranes and chemical barriers. 


Every healthy adult is born with an immune system unique to their own body as it is defined by genetics. It is a highly complex system found all throughout the human body. The immune system is made up of a network of special cells, tissues and organs. Approximately 70% of the body’s immune cells are actually found in the gut.3 Additional organs of the immune system include: tonsils, adenoids, lymph nodes, spleen, bone marrow, thymus and appendix.


The digestive system contains microbes that are called the gut microbiome, which are vital to the immune system. The human stomach has about 38 trillion live micro-organisms and the microbiome is responsible for balancing ‘good’ and ‘bad’ bacteria. The balance between the immune system and the microbiome is crucial and they are continually interacting.


Prebiotics and probiotics have different functions, but work synergistically. Prebiotics feed probiotics by acting as food to help fuel and nourish the ‘good’ bacteria that naturally exists in the gut. Prebiotics include any substrate that is selectively utilized by host microorganisms conferring a health benefit and can be BANANAS • BERRIES • CHICORY • GARLIC LEEKS • ASPARAGUS • ARTICHOKES • TOMATOES • SOYBEANS WHOLE-WHEAT FOODS. Probiotics live microorganisms that, when administered in adequate amounts, confer a health benefit on the host; and are considered the ‘good’ bacteria naturally found in the gut. Probiotics are typically found in fermented foods such as • YOGURT • KEFIR • COTTAGE CHEESE • AGED CHEESE • KIMCHI • SAUERKRAUT • MISO • TEMPEH • CULTURED NON-DAIRY YOGURTS