Chapter 3

Health: The Ultimate Treasure

3.1 Health: Is It More Than Not Falling Sick?

Think about the news items pinned on a bulletin board — soaring diabetes rates, air pollution warnings, obesity figures. They all point to one truth: being healthy is far more than just not falling sick. Health also means feeling physically energetic, staying mentally positive, and enjoying warm social relationships. A truly healthy person takes care of their body, keeps a positive mindset, and remains connected to those around them.

The World Health Organization (WHO) defines health as a 'state of complete physical, mental, and social well-being, and not merely the absence of disease.' This definition captures three inseparable dimensions:

• Physical health — the body functions well, is free from illness, and has enough energy for daily activities.

• Mental health — the mind is calm, positive, and able to cope with stress and difficult situations.

• Social health — a person builds good relationships, adjusts well within peer groups, and contributes to society.

A student who feels lonely, loses sleep, and develops headaches because of isolation is not healthy — even if no germ is involved. This shows that our surroundings and habits are as important as medicines.

3.2 How Can We Stay Healthy?

Our health depends on two broad factors: our lifestyle (how we live) and our environment (our surroundings). Staying healthy means making the right choices in both areas — what to do and what to avoid — every single day.

3.2.1 Maintain a Healthy Lifestyle

Healthy habits are the foundation of a healthy life. Here is what you should practise:

• Eat a balanced diet rich in fruits, vegetables, and whole grains. Avoid processed, fatty, or sugary food and drinks.

• Stay physically active — play outdoors, walk, run, cycle, or exercise regularly.

• Limit screen time and spend more time in nature.

• Get enough sleep so your body and mind can rest and recover.

• Practise yoga or breathing exercises like pranayama regularly.

• Say 'NO' to harmful substances like tobacco, alcohol, and addictive drugs.

• Manage stress — make time every day to relax, reflect, or meditate.

Equally important is knowing what not to do: excessive screen time, skipping meals (especially breakfast), sleeping very late, and eating junk food daily — all of these slowly weaken both the body and the mind.

3.2.2 Keep the Environment Clean

A clean environment directly protects our health. Dirty, polluted areas are breeding grounds for flies and mosquitoes, leading to frequent illness. Clean air and water are non-negotiable basics — air pollution from vehicles and factories can trigger coughing and asthma. The Air Quality Index (AQI) tells us how safe the air around us is; a lower AQI means cleaner, healthier air.

Our feelings and relationships matter too. Even in a spotless home with a nutritious diet, we can feel unwell if we are lonely or upset. Spending time with friends and family, talking, laughing, and having fun are just as essential for keeping our mind healthy.

3.3 How Do We Know That We Are Unwell?

Our body constantly works to maintain balance. When something goes wrong inside, it sends us signals in two forms:

• Symptoms — what we feel, such as pain, tiredness, or dizziness. Only the person experiencing them can report a symptom.

• Signs — what can be seen or measured by others, such as fever, rash, high blood pressure, or swelling.

Together, symptoms and signs help doctors figure out what is making us unwell and decide on the right treatment. A simple example: feeling pain is a symptom; a thermometer reading of 39°C is a sign. Never ignore these signals — they are your body asking for help.

3.4 Diseases: What Are the Causes and Types?

A disease is a condition that disrupts the normal working of the body or mind. It occurs when one or more organs or organ systems stop functioning properly. Disease-causing organisms — bacteria, viruses, fungi, worms, and protozoa — are called pathogens. But not all diseases are caused by pathogens; some arise from poor nutrition, unhealthy lifestyles, or environmental factors.

All diseases fall into two broad categories:

• Non-Communicable Diseases (NCDs) — diseases like cancer, diabetes, and asthma that are not caused by pathogens and do not spread from person to person. They are usually linked to lifestyle, diet, and/or environment.

• Communicable Diseases — diseases caused by pathogens that can spread from one person to another. Examples: typhoid, dengue, flu, chickenpox, and COVID-19.

In recent years, NCDs like diabetes, heart disease, and cancer have become the most common cause of death in India — driven by changes in lifestyle such as eating more processed food, getting less exercise, and living longer lives. Understanding the difference between the two types helps us know how diseases spread and how to prevent them.

3.4.1 How Are Communicable Diseases Caused and Spread?

All communicable diseases are caused by pathogens that enter our bodies through various routes. The main modes of transmission are:

• By air: An infected person coughs or sneezes, releasing droplets carrying pathogens — others breathe them in. Example: common cold, TB, measles.

• By direct contact: Touching an infected person directly — shaking hands, touching infected skin. Example: chickenpox, ringworm.

• By indirect contact: Sharing personal items like towels, handkerchiefs, or utensils of an infected person.

• Through contaminated food and water: Eating or drinking food and water that contain pathogens. Example: cholera, typhoid, hepatitis A.

• Through vectors: Insects like mosquitoes and houseflies carry pathogens from one host to another. These disease-transmitting insects are called vectors. Example: malaria (mosquito), dengue (mosquito).

• Through parasites: Worms that live inside the body (especially the digestive system) feed on nutrients from the host and live as parasites. They spread through contaminated food, water, soil, or contact with infected animals. Example: Ascariasis (roundworm).

Table 3.1: Common Communicable Diseases — At a Glance

By studying how these diseases spread, we can protect ourselves with these simple but powerful steps:

• Keep yourself and your surroundings clean at all times.

• Practise basic hygiene every day.

• Wash hands thoroughly with soap and water to remove pathogens.

• Cover your mouth and nose while coughing or sneezing.

• Wear a mask in crowded places.

• Avoid sharing personal items like towels and handkerchiefs.

• Keep your home, food, and drinking water clean.

• Stay home and rest when you are unwell — this helps you recover faster and prevents spreading the disease to others.

3.4.2 How Are Non-Communicable Diseases Caused?

NCDs like cancer, diabetes, and asthma are not caused by pathogens. Instead, they result from a combination of lifestyle choices, dietary habits, and environmental exposure. They are the leading cause of death in India today.

A special group within NCDs is deficiency diseases — caused by a lack of specific nutrients in the diet. Examples you may recall from Grade 6: scurvy (Vitamin C deficiency), anaemia (iron deficiency), and goitre (iodine deficiency). These diseases do not involve any pathogen and cannot spread from person to person.

Diseases like cancer, diabetes, and asthma may last for more than three months — they are therefore called chronic diseases. Diabetes is particularly alarming: India now has one of the highest numbers of people with diabetes in the world, driven by hormonal imbalances, unhealthy eating, lack of physical activity, and obesity.

Common lifestyle-related NCDs and suggested changes include:

• Obesity: Caused by excess calorie intake and lack of exercise. Managed by eating a balanced diet and exercising regularly.

• Diabetes: Signs include frequent urination, excessive thirst, weight loss, tiredness, and slow healing of wounds. Managed through diet, exercise, and medication.

• High blood pressure: Often called the 'silent killer' as it shows no obvious symptoms. Managed by reducing salt intake, managing stress, exercising, and avoiding tobacco and alcohol.

• Asthma: Triggered by air pollution, allergens, or stress. Managed with inhalers, avoiding triggers, and maintaining clean indoor air.

• Cancer: Linked to tobacco use, poor diet, radiation, and certain infections. Early detection through screening is crucial for effective treatment.

3.5 How to Prevent and Control Diseases?

'Prevention is better than cure' — this holds true for both communicable and non-communicable diseases. The most powerful tools we have are cleanliness, immunity, and vaccination.

Case Study — Odisha Community Sanitation Campaign: In Bhadrak district, Odisha, a community-led campaign helped more people build and use toilets, drastically reducing open defecation. The result: improved child health and far fewer cases of diarrhoea and infections. The lesson is clear — simple sanitation measures can save lives.

Ability of the Body to Fight Diseases

Some people fall sick more often than others, even in the same environment. The reason is immunity — the natural ability of our body to fight diseases. Our immune system is a remarkable defence network that identifies and destroys harmful pathogens before they can cause serious harm.

We can boost and train our immune system using vaccines. A vaccine introduces the immune system to a weakened, dead, or harmless part of a pathogen, teaching it to fight that germ without causing the actual disease. The protection built this way is called acquired immunity.

Vaccines can be made from:

• Weakened or dead pathogens (e.g., viruses or bacteria)

• Inactive or harmless parts of a pathogen

• Instructions that teach body cells to make a harmless part of the germ (e.g., newer mRNA-type vaccines)

Example: A tetanus shot — given after an injury — contains an inactivated bacterial toxin. The immune system learns to recognise it and builds protection without experiencing the disease itself.

Vaccines protect people of all ages — from infants to the elderly. They are preventive, not curative: they stop a disease before it happens but cannot treat you once you are already sick. Every vaccine is carefully tested for safety. Getting vaccinated protects not just you, but everyone around you.

3.5.1 Treatment of Diseases

When our immune system fails to stop a bacterial infection, we need medical help. Doctors prescribe antibiotics — medicines that kill bacteria by targeting parts of bacterial cells that differ from human cells. Antibiotics work only against bacterial infections; they are completely ineffective against viruses or diseases caused by protozoa.

Despite their life-saving power, antibiotics are now under threat from antibiotic resistance — a phenomenon where bacteria that were once killed by an antibiotic survive and multiply despite treatment. This happens through overuse, incomplete dosing, and using antibiotics for viral infections or in livestock. Resistant bacteria spread through hospitals, communities, food, and soil — making infections increasingly difficult and sometimes impossible to treat.

To combat antibiotic resistance, always remember:

• Use antibiotics only when prescribed by a doctor. Never self-medicate.

• Complete the full prescribed course, even if you feel better midway.

• Never use antibiotics for viral infections like a cold, cough, or flu.

• Do not pressure pharmacists for antibiotics without a prescription.

• Avoid giving antibiotics to livestock without veterinary guidance.

Traditional medicine systems — Ayurveda, Siddha, and Unani — use herbs, oils, and minerals to manage common health issues and promote recovery. While they are valuable for everyday wellness and some conditions, they may not be effective for all diseases or at all stages of illness.

For non-communicable diseases, treatment focuses on managing symptoms and improving quality of life through medication, lifestyle changes, and rehabilitation. Early diagnosis and continuous care are critical to slow disease progression and prevent complications.