Health: The Ultimate Treasure

Class 08 Science

As per the World Health Organization (WHO), health is defined as a state of complete physical, mental, and social well-being, and not merely the absence of disease.

A healthy person can perform various tasks more efficiently and cope well in different and difficult situations. A healthy person can adjust well with peer groups and other members of society.

How Can We Stay Healthy?

Staying healthy means eating nutritious food, maintaining hygiene, staying in a clean place, exercising regularly, getting proper sleep, spending time with family and friends, and having a positive attitude.

Maintain a Healthy Lifestyle

  • Eat a balanced diet with plenty of fruits, vegetables, and whole grains.
  • Avoid processed, fatty, or sugary food and drinks.
  • Stay physically active by playing outdoors, walking, running, cycling, or exercising.
  • Limit screen time and spend more time in nature.
  • Get enough sleep to help your body and mind rest and recover.
  • Practice yoga or simple breathing exercises like pranayama regularly.
  • Say ‘NO’ to harmful substances things like tobacco, alcohol, and addictive drugs.

How Do We Know That We Are Unwell?

Our body usually works in a certain way to keep us healthy. When we feel unwell, it means something inside us may not be working as it should. We may have symptoms, such as pain, tiredness, or dizziness, and signs like fever, rash, high blood pressure, or swelling that indicate we are unwell.

A symptom is what we feel (like pain), while a sign is something that can be seen or measured (like high body temperature when we have fever). These help doctors understand what might be making us unwell.

Diseases

A disease is a condition that affects the normal working of the body or mind. It can happen when one or more organs or organ systems stop functioning properly.

Some diseases are caused by germs like bacteria, viruses, fungi, worms, or even by protozoa (single-celled organisms). These disease-causing organisms are called pathogens.

Other diseases may result from poor nutrition or an unhealthy lifestyle. Some diseases last for a short time, while others can continue for a long time and need regular treatment or care. Diseases can be grouped into two major types based on their causes and how they spread:

  1. Non-communicable diseases
  2. Communicable diseases

Non-communicable diseases

Some diseases, like cancer, diabetes, or asthma, are not caused by pathogens and do not spread from one person to another. They are usually linked to lifestyle, diet, and environment.

Communicable diseases

Diseases caused by pathogens are called communicable diseases. They can spread from one person to another. Some examples of communicable diseases are typhoid, dengue, flu, chickenpox, and COVID-19.

Communicable Diseases

All communicable diseases are caused by pathogens. These pathogens can enter our body through the air we breathe or by consuming contaminated food or water and more.

These pathogens spread from one person to another through air, when an infected person coughs or sneezes, or through direct contact like shaking hands, or indirectly by sharing personal items of an infected person. Some of the communicable diseases spread through contaminated drinking water or food. Some pathogens are also spread by insects like mosquitoes and houseflies. These insects are called vectors.

Some common communicable diseases:

  • Common cold and influenza
  • Chickenpox
  • Measles
  • Tuberculosis (TB)
  • Hepatitis A
  • Cholera
  • Typhoid
  • Ascariasis (roundworms)
  • Malaria
  • Dengue fever (Break bone fever)

Some infectious diseases are caused by worms that live inside our bodies, especially in the digestive system. They feed on nutrients and live as parasites - organisms that live in or on another living being. These worms usually spread through contaminated food, water, soil, or contact with infected people or animals.

Non-communicable Diseases

Non-communicable diseases like cancer, diabetes, and asthma are linked to lifestyle, diet, and/or environment. Diseases like scurvy, anaemia, and goitre, are caused by a lack of specific nutrients in the diet. These are called deficiency diseases and are also non-communicable.

Diseases such as cancer, diabetes, and asthma may often persist for a long time (more than 3 months) and are referred to as chronic diseases.

Diabetes is a common disease which is becoming more prevalent in adults as well as children. It often develops due to a combination of hormonal imbalances, unhealthy eating habits, lack of physical activity, being overweight or obese, and other reasons.

Non-communicable diseases:

  • Obesity
  • Diabetes
  • High blood pressure

Immunity

The natural ability of our body to fight diseases is known as immunity. Our body has a special system called the immune system that helps fight against diseases.

Vaccines help prevent serious infections caused by viruses and bacteria. A vaccine helps our body fight certain diseases by training the immune system to recognise and attack harmful germs. It provides acquired immunity - protection developed after exposure to a pathogen or a vaccine. Vaccines can be made in different ways - from weakened or dead pathogens (like viruses or bacteria), or from inactive or harmless parts of the pathogen.

Edward Jenner and the smallpox vaccine

Smallpox was a deadly disease that caused blisters and killed millions. A milder disease called cowpox, seen in cows, could also infect humans. In the late 1700s, English doctor Edward Jenner discovered that people who had cowpox did not get smallpox. This led to the invention of the first vaccine and helped protect people from smallpox.

Treatment of Diseases

If our immune system fails to protect us against an infectious disease, we fall ill and need to visit a doctor. The doctor may give us medicines called antibiotics, which kill the bacteria that might have caused the disease. Antibiotics work only against bacterial infections because they target parts of bacterial cells that are different from human or other animal cells. They do not work against viruses or diseases caused by protozoa.

Though antibiotics are effective in protecting us against bacterial infections and have saved millions of lives since their discovery, their indiscriminate use has led to a decline in their effectiveness. Nowadays, there are news headlines about antibiotic resistance, a phenomenon where bacteria that were earlier killed by a given antibiotic are found to survive and multiply despite treatment with that antibiotic. This makes common infections harder to treat and increases the risk of complications, prolonged illness, and even death.

Traditional medicine systems like Ayurveda, Siddha, and Unani have been used in India for many years to manage common health problems. They use natural substances like herbs, oils, and minerals for managing illnesses and promoting recovery, and focus on a healthy lifestyle and balanced diet. While these systems can help with some conditions, and are useful for everyday well-being, they may not be effective for all diseases and at all stages.

Therapies for non-communicable diseases focus on managing symptoms and improving quality of life through medication, lifestyle changes, and rehabilitation. Early diagnosis and continuous care are key to control the disease progression and prevent complications.