What is immunity?We are all surrounded by numerous microorganisms such as viruses, bacteria, fungi, and protozoa. We are exposed to them through the food we eat, the air we breathe, or the water we drink. While most of these microorganisms are harmless, some cause diseases. These infection and disease-causing microbes are known as pathogens. Every living organism has a mechanism designed to defend itself against these unwanted pathogens. This mechanism either kills these harmful microbes from entering the body or prevents them from entering the body in the first place. This defence mechanism is known as immunity.
Among human beings, a structure known as the immune system (made up of a complex network of cells, tissues, chemicals, proteins, and organs) confers immunity. The primary functions of an immune system are as follows:
● Protect the body: The immune system defends the body against harmful and infectious pathogens, viruses, and bacteria, thereby safeguarding the body's integrity. The immune system also designs an immune response that deactivates or eliminates germs.
● Differentiate between self and non-self: A good and healthy immune system also can tell the self from non-self. This is a critical function, for if it fails to do so, it will end up attacking itself and cause auto-immune diseases.
● Discard the unwanted cells: The immune system helps to clear up and discard the body’s own infected or dead cells and the resultant malfunctioning.
Types of ImmunityThe body’s immunity can be classified into different types depending on how it has developed. Let’s look at them in detail below.
● Innate immunity: This form of immunity is inherent in all of us. To put it simply, it is the immunity that we are born with, and there’s a substantial genetic influence on the same.It’s function is therefore quite generic, which is that it attacks any germs or pathogens that threaten the body. This innate component of the immune system immediately triggers an immune response once the pathogen enters the body. Furthermore, it informs the acquired or adaptive immune system about the pathogen’s entry to be better prepared should the pathogen invade the body again in the future.
Innate immunity has two essential components, which are as below:
● The external component: This is an essential part as it is the first line of defence. It acts as a protective barrier against harmful pathogens, disallowing them from entering the body. This includes organs like the skin, stomach acid, and mucous membranes.
● The internal component: Once the pathogens enter the body, this component of your innate immunity gets activated. This component includes mechanisms like inflammatory response, fever, and phagocytosis, which is a process by which natural killer cells or macrophages of our body can circle the germs and kill them one by one.
● Adaptive or acquired immunity: If your innate immunity fails to evade the pathogens, that’s when the adaptive or acquired immunity gets activated. The name of this immunity is relatively self-explanatory. Adaptive immunity develops over a period of time as the body is exposed to more and more pathogens. This form of immunity takes time to develop and targets only specific pathogens. Suppose a particular pathogen manages to get past the innate immunity and enter the body. In that case, the adaptive or acquired immunity starts working, whereby the body then remembers the pathogen through immunological memory. This way, it provides long-term immunity.
This form of immunity can further be differentiated into the following types:
● Active immunity: As your body gets exposed to different pathogens, it automatically develops immunity cells like B-cells and T-cells. The role of these cells is to clear and discard the live germs by creating antibodies, also known as humoral immunity or cell-mediated immunity. Simultaneously, they also trigger the immunological memory versions of these cells that help the body respond to future infections caused by a similar pathogen. The active acquired immunity can further be classified into two different types - natural and artificial.
1. Natural active acquired immunity: This form of active acquired immunity is activated when the body is naturally exposed to pathogens due to infection. Through exposure, the body automatically produces antibodies that fight off the pathogen. At the same time, the memory cells are created that help the body with a more prompt and efficient immune response the next time the same type of pathogen attacks the body.
2. Artificial active acquired immunity: Anything that’s not naturally created,is referred to as artificial. When the infection occurs in a controlled manner, such as in the case of a vaccination, the resultant acquired immunity is artificial in nature. During vaccination or immunization, an inactivated or dead germ, antigens, or toxins are injected into the body. While this does not trigger a severe infection or disease, it aids the body in developing the right kind of antibodies to fight the pathogen. In this way, too, memory cells are created to help the body fight the pathogens if there is ever a re-infection in the future. Examples of this are vaccinations against COVID-19, tetanus, whooping cough, diphtheria, etc.
● Passive immunity: This is another form of acquired immunity. Passive acquired immunity gets activated when the body is provided with readymade antibodies to fight a particular infection. This form of immunity is provided to high-risk patients or those with immunodeficiencies. Those with immunodeficiencies are not able to create antibodies on their own. An example of this would be when a patient is given intravenous immune proteins prepared out of sterile blood plasma, which contains antibodies for a particular disease. This will automatically provide quick but temporary protection against the disease. However, given there is no exposure to the germ, the body cannot develop immunological memory, and that’s why it won’t be able to defend the body against the occurrence of future infections. The protection that one receives from this is thus short-lived.
Like active immunity, even passive immunity is further categorized as natural and artificial immunity.
1. Natural passive acquired immunity: This form of immunity can be best explained with an example of a new-born baby. For the initial years, a new-born baby’s immunity is dependent on the mother’s immunity. Before the baby is born, the foetus gets certain specific antibodies from the mother through the placenta. These antibodies protect the baby till the time its immune system gets fully developed. Once it is born, it receives the same immunity through the mother’s milk. This form of passive immunity protects the baby in the initial stages of infancy.
2. Artificial passive acquired immunity: This form of immunity is developed in a controlled environment by introducing readymade antibodies, particular to a disease in question. This is given to an immunologically deficient person to help him fight the infection. For instance, the blood plasma of a COVID survivor is intravenously given to another person with a weakened immune system to fight the disease.
● Herd immunity This is an indirect form of developing immunity. For this type of immunity to get activated, many people need to develop antibodies against a particular infection, either through vaccination or prior illness. Once that happens, the remaining people automatically get protected. This takes a lot of time, as the infectious/contagious disease chain needs to break, thereby stopping the virus from spreading any further. Having said that, it’s always best to stay protected from potent pathogens by getting vaccinated.
Your immune system is perhaps the most essential system in your body that keeps it healthy and running. To fight any infection and protect yourself from falling sick, you need to have a robust immune system. That is when immune booster foods and supplements come into the picture. Ensure that you have a healthy diet comprising essential nutrients like vitamin C,D,E, zinc, selenium, iron, calcium, magnesium, folate, antioxidants. If your food doesn’t provide you with sufficient nutrients, don’t shy away from including dietary supplements in your daily routine.
Wellbeing Nutrition offers a wide range of immunity-boosting products that cater to the body's specific needs. These supplements include Daily Greens, Grandma’s Kadha, Probiotics + Prebiotics, and Apple Cider Vinegar,with 2x the mother. At the same time, if you are looking for something for your skin or any other specific ailment or deficiency, then Wellbeing Nutrition’s Skin Fuel or their most recent series of Melts, (which are thin oral strips for throat, D3, B12, sleep, and hair) are the right immunity booster products for you!
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