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Why Do We Fall ill

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Health is one of the most crucial and essential aspects of every individual’s life. Not being fit or healthy enough disables one from carrying out normal day-to-day activities. 


Why do we fall ill? Or Why do you fall ill? Or Why do we fall sick? There are many reasons for these questions. We may fall ill due to various reasons, and a few of them are listed below.

  • We can fall ill if we dwell in a surrounding that has polluted air, water or any harmful insects. For example, Dengue or Malaria.

  • Lack of personal hygiene also causes numerous diseases.

  • Any individual’s economic condition can also be instrumental in determining the person’s well-being

  • We could fall ill because of the compromises in our immune system, which can also give rise to different autoimmune diseases

  • Mental health always has an impact on physical health. For example, clinical depression may cause either weight loss or loss of appetite.


Significance of Health

We should keep hearing how important it is to be healthy and possibly what could be the consequences of avoiding taking care of ourselves, let us understand why it is so important to stay healthy.

  • It is essential to stay healthy because it helps one to carry out all the fundamental activities regularly.

  • Eating proper healthy and right food helps in keeping one fit and aids in combating diseases.

  • The physical environment contributes to a person’s well-being in a greater way. Thus, it becomes very crucial to always stay in a clean and healthy environment.

  • Public cleanliness is an important thing for every individual. Proper treatment of sewage and garbage in our surroundings play a key role in disease prevention.

  • Being fit and happy has a huge impact on one’s development, both personally and professionally as well.

  • Social equality and harmony are important to be healthy.


Immune System

The immune system is the body's protection system. It acts as a deterrent to disease-causing germs. The immune system is made up of a variety of cells and substances. Pathogens are thwarted by these cells and substances. Pathogens include parasites, fungus, bacteria, viruses, and haptens, among other things. When haptens come into touch with a protein, they can trigger an immunological response.

These cells and chemicals may be found in all of the body's tissues, as well as lymphoid organs. Its primary function is to prevent or remove microbial diseases. The most essential cells in the immune system are white blood cells, often known as leukocytes. They're mostly in charge of eliminating disease-causing germs or chemicals. Antibodies from lymphoid organs, tissues, and proteinaceous molecules are also vital in the defence system.

There are two types of immunological responses:

  1. Humoral Immunity: B cells have a role in humoral immunity. Antibodies are soluble molecules secreted by B cells into bodily fluids. Antibodies bind to bacteria and other harmful substances in the bloodstream and destroy them through an antigen-antibody response.

  2. Cell-mediated Immunity: T cells, also known as cytotoxic T cells, play a role in this. These cells are unique to an infected target cell and use a variety of techniques to destroy the infected cell.


Types of Immunity

Innate, adaptive, and passive immunity are the three forms of immunity that humans have:

Innate Immunity: Innate (or natural) immunity is a form of broad protection that everyone is born with. The epidermis, for example, works as a barrier to keep viruses out of the body. In addition, the immune system can tell whether some invaders are alien and potentially harmful.

Adaptive Immunity: Adaptive immunity (also known as active immunity) is a type of immunity that develops over time. When we are exposed to illnesses or are inoculated against them with vaccinations, we acquire adaptive immunity.

Passive Immunity: Passive immunity is "stolen" from another source and only lasts for a brief period of time. Antibodies in a mother's breast milk, for example, provide a newborn with temporary protection against illnesses to which the mother has been exposed.


Any abnormal condition affecting an organism is referred to as a disease. These are the medical conditions that involve a pathological method/process associated with a few specific symptoms.


Every disease has an origin for sure. But some diseases are difficult even to diagnose due to the confusing symptoms. Diseases may be bacterial, autoimmune, cancerous, sexually transmitted, digestive, and many more. They can be cured by following numerous strategies like giving antibiotics, medications, and surgeries if needed.


Antibiotics are the drugs that block the bacteria’s biochemical pathways that cause diseases. These don’t work against viral infections due to the reason the viruses depend upon the biochemical mechanisms of the host.


Types of Diseases

We generally say we have fallen sick or have a disease the time when we feel there is something that went wrong with either one of our organs or organ system. Because of this, our normal body functioning is affected. Our body gives some signs or hints when we have a disease at a starting stage. These signs are nothing but symptoms. Some of the common symptoms include cold, headache, cough, nausea, and so on.


Diseases normally can be of two types, they are:

  • Acute Diseases - Acute diseases are the ones that last for either a short period of time, a day, a week, or a few weeks. For example, typhoid, Chickenpox, a common cold, and so on.

  • Chronic Diseases - Chronic diseases are the ones that last for a longer time or even a complete human life. For example, Cancer, HIV, and more related ones.


There can be Two Types of Immediate Causes of Diseases.

Infectious causes

If microbes happen to be the immediate cause of a disease, then they are listed under infectious causes.


Non-infectious causes

These are not caused by any infectious agents or external factors. Besides, usually, these are caused by internal factors. For example, diabetes, cancer, high/low blood pressure, and other related ones.


Prevention of Diseases

Below are a few tips for disease-free and healthy living.

  • Go for routine/regular checkups. This helps to diagnose the disease at its early stage, and the treatment becomes easier. Thereby, we can make sure to go for health screening tests.

  • Smoking affects the quality and length of a person’s life. Quitting this habit can undoubtedly improve the quality of such a person’s life and prevents their body from any further severe infections occurring.

  • Doing physical exercises daily keeps us active. It also energises our bodies and keeps us healthy.

  • A balanced diet is an essential aspect of the prevention of diseases. Consuming healthy and nutritional food keeps us fit and prevents any diseases.

  • Obesity is one of the greater causes of heart problems and increased cholesterol. Weight reduction can help us get rid of the risks of being ill.


Key Points on Why do We fall Ill

A few cases on why do we fall ill, reasons are listed below:

  • We might fall ill due to the reason we live in polluted surroundings or lack of personal hygiene.

  • It is so necessary to adopt certain strategies to stay healthy and prevent diseases on our own.

  • One should remain active by taking daily exercises.

  • Eating healthy food helps in the prevention of diseases.

  • Smoking and alcohol consumption are the two primary reasons for the deteriorating health of any individual.

  • Physical and mental health are just like two sides of the same coin. Any imbalance in one can immediately affect the other.



Being fit and happy has a huge impact on one's development, both personally and professionally. Eating proper, healthy and right food helps in keeping one fit and aids in combating diseases. Mental health always has an impact on physical health; depression may cause weight loss or loss of appetite.

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FAQs on Why Do We Fall ill

1. Why do we fall ill, despite having a strong immune system?

In general, there are two reasons. The immune system is reactive, so an unrecognised or new pathogen has to get into cells before they sound the alarm, and it takes some time for the trillions of first responders to be recruited from stem cells in our bone marrow. The second reason is, the invaders can quickly multiply, and be hard to defeat, especially if the immune system is weak.


If we have experienced the pathogen earlier, by previously fighting it or by vaccination, our immune system will destroy it on contact by fighting against, in the bloodstream usually, before it can get into a cell.


Because all of us have sitting jobs in the current generation, we don’t use our muscles to enough extent to stretch and maintain them, and as muscle mass declines, immunity might decline.


It completely resides on our end to protect our health, and as we see the chronic diseases of ageing happening at younger ages, we should pay attention. Exercise is not just a good idea; it is also mandatory now, to survive especially from diseases like bone problems, paralysis, and more. Exercise even acts as a drug sometimes.

2. Mention some healthy ways to strengthen the Immune system?

Our first defence line is to choose a healthy lifestyle. Following general good-health guidelines is the single, simple, and best step we can take towards naturally keeping our immune system strong and healthy. Every part of your body, along with the immune system, functions in a better way when it is protected from environmental assaults and bolstered by healthy-living strategies such as the ones listed below.

  • Exercise regularly

  • Do not smoke

  • Maintain a healthy weight

  • Eat a diet high in fruits and vegetables

  • Drink alcohol only moderately

  • Get adequate sleep

  • Try to minimise stress

  • Take proper steps to avoid infection, like washing your hands frequently and cooking meats thoroughly.

By doing the above mentioned do’s, one can question them as, why do fall ill if we maintained all these preventive measures.

3. How Immune system work?

The immune system strives to identify and eliminate the antigens,when the body detects foreign substances (known as antigens).

Antibodies are produced when B cells are activated (also called immunoglobulins). The antigens are binded by these proteins that are particular to them. Antibodies are normally retained in our systems once they're generated so that they can help if we have to battle the same infection again. That's why a person who contracts an illness, such as chickenpox, is unlikely to get it again.

Antibodies can identify and lock onto an antigen, but they can't kill it on their own. T cells are in charge of this. They annihilate antigens that have been tagged by antibodies, as well as contaminated or altered cells. (Some T cells are even referred to be "killer cells.") T cells also assist in the signalling of other cells (such as phagocytes) to perform their functions.

4. What should be the approach to maintain good health?

It is critical to establish healthy behaviours at a young age. Such healthy behaviour will help you to make wise decisions for your family. Because children copy their parents, it is critical to set a positive example for them. The suggestions below can assist you and your family in maintaining a healthy and happy lifestyle.

  • Start your day with a nutritious breakfast. This will give you enough energy to go through the day.

  • Allow your children to assist you in planning and preparing one dinner every week.

  • Always eat meals as a family whenever possible.

  • Chew your food thoroughly by taking out time to eat. To indicate to the body that you are full, the brain takes 20 minutes.

  • Increase your intake of fresh fruits and vegetables. Aim for two cups of fruit and two and a half cups of veggies every day.

  • Increase your intake of whole grains. Oats, brown rice, rye, and whole-wheat pasta are other examples. Every day, consume at least 3 ounces of whole grains.

  • Drink a lot of water. Water, low-fat or nonfat milk, and low-calorie drinks are all good choices.

  • Serve a wide range of dishes.

  • Small servings of food should be served.

5. How do diseases affect our bodies?

Infection does not always imply illness. An infection in your body indicates that virus, bacteria or other organisms entered your body and began multiplying. A Disease occurs when the cells in your body are destroyed as a result of infection and signs and symptoms of sickness arise, which occurs in a tiny percentage of infected people.

When you are infected, your immune system begins to work at a much faster rate. White blood cells, antibodies, and other processes work to eliminate the foreign intruder from your body. Many of the symptoms that cause a person to suffer during an illness—fever, malaise, headache, rash—are caused by the immune system's efforts to rid the body of the infection. You can learn more about the Immune system and Diseases in Vedantu. You will get different study materials on the Vedantu website and app which will help you to understand this topic better. 

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