To keep a close watch on all parts of the body and keep them from coming under any harm from biological and environmental intruders(1) – that’s the primary function of the immune system, or our body’s defence system. 

We have already explored the importance of the immune system and the types of immunity in a previous piece. In this one, let’s delve into what a weak immune system actually implies and some of the factors that contribute to it.

What is a weak immune system?

When the immune system, which is a complex network of cells and tissues, is in a weakened state, our defence against intruders is lowered. We are not able to effectively fight harmful trespassers and end up being susceptible to health disorders.

A feeble immune system may be caused by several reasons, and it may last for a short time or it may be permanent. 

What are some factors that lead to lowered immune response?

  1. Infections, even minor ones such as influenza, can weaken the immune system. But if the infection targets immune system cells, that may lead to severe immune system suppression, as is the case of human immunodeficiency virus (HIV). In the case of HIV, the focus of attack are the T cells of immune system. As the T cells count decreases, the person becomes increasingly susceptible to infections by other pathogens as well(3).
  2. Smoking cigarettes has a detrimental effect on the innate and adaptive immune systems. It weakens the normal defence function of immune system(4). It may increase autoimmunity and reduces protection against infections.

  3. Genetics plays an important role in how the immune system works, especially adaptive immunity(5). The heritable immune system traits are a large fraction of our immune system, and genetics is a major underlying cause in determining if a person inherits a weak immune system. Primary immune deficiency diseases (PIDDs) are inherited and they are the result of certain genetic disorders; a person with this disorder may be more susceptible to frequent infections(3).

  4. Pregnancy can affect immunity levels as well; when a woman is pregnant, her immune system may be suppressed, which makes her vulnerable to common infections(3). The pregnant woman’s immune system makes certain changes and adapts itself, so that the mother’s body does not reject her own foetus as a foreign intruder(6).
  1. Certain nutrient deficiencies also seem to have an effect on the functioning of immune system. A diet which is not providing adequate amounts protein and micronutrients such as Vitamin A, Vitamin E, zinc and iron will lead to a compromised or a weak immune system(7). A lack of dietary antioxidants also disturbs the delicate balance of free radicals and antioxidants in the body and may lower the immune function. Sufficient amounts of dietary antioxidants help in correcting or preventing the imbalance of free radicals and antioxidants in the immune system cells(8)

Are allergies and autoimmune disorders sign of a weak immune system?

An overactive immune system, as seen in the case of allergies, is also a sign of a dysfunctional or compromised immune system. Allergens or certain substances in the environment elicit an abnormal response from an overactive immune system, which is seen in people who are allergic towards certain foods or substances such as dust or pollen in the air. 

In other words, it can be said that the immune cells in these people are hypersensitive to specific elements. If a person’s immune system is functioning normally, these substances are harmless; the cause of this overactive response is not very clear, but it is generally due to certain genetic traits(9)(3).

Sometimes our immune system recognises our own body cells as antigens and releases antibodies or cells that react against itself; this is termed as an autoimmune disorder. How this phenomenon is initiated is still not clear, but it can also be a kind of weak immune system. Think of it this way – our own immune system is cheated into believing that a few cells in our own body are actually trespassers, and they need to be destroyed. 

Type 1 diabetes, lupus and rheumatoid arthritis are disorders which are the result of the autoimmune response(9). Autoimmunity may be organ-specific, such as with Type 1 diabetes, or it can be systemic – such as with lupus, in which the whole body is involved(3). An autoimmune disorder or hypersensitivity of the immune cells towards a specific substance can also be clubbed under weak immune system.

Simply put-

Just as there are several factors and conditions that may result in a person having a weak immune system or lowered immune response, there are several ways to boost immunity as well.

How to boost your immune system?

Consuming a balanced diet including dietary antioxidants and adaptogens can ward off any nutritional deficiencies which may lead to having a weak immune system. As far as diets go, we’ve highlighted the benefits of low-carb diets here (Link – Nutrition 8) and intermittent fasting and time-restricted eating here (Link – Nutrition 9)

At the same time, quitting smoking is a good idea to bolster the defence mechanism. If you’ve been diagnosed with lifestyle diseases such as diabetes – don’t lose heart! Persevere and work towards keeping the critical parameters under control. 
Now, more than ever – in light of the global spread of the novel coronavirus – it is time to pay attention to our immunity and take measures that would, to a large extent, strengthen one’s immune system.