Chapter 3: Health: The Ultimate Treasure

When the common cold virus enters your body, your immune system detects it as a foreign pathogen and activates defense mechanisms. You experience symptoms like a runny nose, sore throat, sneezing, and mild fever — these are actually signs that your body is fighting the infection. The fever helps slow down the virus, while mucus traps and expels it. After a few days, your immune system usually wins and you recover.

Smallpox and polio have been controlled or nearly eradicated through mass vaccination programmes, which trained people's immune systems to fight these diseases before infection. In contrast, diabetes and heart disease are non-communicable diseases linked to modern lifestyle choices such as eating processed food, lack of exercise, obesity, and stress. As living standards change, more people adopt unhealthy habits, making these lifestyle diseases more prevalent. Vaccines cannot prevent lifestyle diseases, so awareness and healthy habits are the only solution.

Yes, climate change can contribute to the rise of new or re-emerging diseases. Rising temperatures and changing rainfall patterns create favourable conditions for disease-carrying vectors like mosquitoes to spread to new regions, increasing diseases like malaria and dengue. Extreme weather events can contaminate water supplies, leading to waterborne diseases. Additionally, melting permafrost could release ancient pathogens that humans have no immunity against, potentially causing new outbreaks.

When we are stressed or worried, our body releases stress hormones like cortisol, which can weaken the immune system over time, making us more vulnerable to infections. Chronic stress can lead to headaches, disturbed sleep, loss of appetite, and high blood pressure. Poor mental health and emotional distress are closely linked to physical health problems like digestive issues and heart disease. This shows that mental and physical health are deeply connected, as the WHO definition of health also includes mental well-being.

Some groups are more vulnerable during disease outbreaks due to factors like weaker immunity (elderly, infants, or those with chronic illnesses), poor nutrition, lack of access to clean water and sanitation, and crowded living conditions. People in poverty may not have access to healthcare, vaccines, or proper hygiene facilities, making them more susceptible. Social factors like lack of education about hygiene and prevention also play a role. This is why community health campaigns targeting vulnerable groups are very important.

The boy's health problems were caused by a combination of loneliness, excessive screen time, and social isolation in his new environment. His habit of spending too much time on his phone to cope with loneliness led to headaches, weight loss, and poor sleep — showing how unhealthy habits can harm physical health. His surroundings (new city, no friends, busy parents) affected his mental and social well-being, which in turn impacted his physical health. This reflects the WHO definition that health includes physical, mental, AND social well-being.

Good habits: Maintaining personal hygiene, eating a balanced diet, exercising regularly, meditating daily, sleeping on time, drinking enough water, and spending time outdoors. Bad habits: Spending too much time on screens, eating junk food daily, sleeping very late, skipping meals (especially breakfast), avoiding physical activity, and consuming tobacco or alcohol. Students should reflect on which good habits they already follow and set a goal to adopt more. Reducing bad habits and replacing them with healthy ones is the key to long-term well-being.