Health is not just the absence of illness. It is the body, mind and surroundings all working well — and food is where it starts.
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A balanced diet has all the nutrients in the right amounts. Each one does a different job.
🍱 What each nutrient does
| Nutrient | Job | Found in |
|---|---|---|
| Carbohydrates | give energy | rice, wheat, potato, sugar |
| Fats | store energy, keep warm | oil, ghee, nuts |
| Proteins | build and repair the body | dal, milk, eggs, fish, soya |
| Vitamins | protect against disease | fruit and vegetables |
| Minerals | bones, teeth, blood | milk, green leaves, salt |
| Roughage | helps food move through | whole grain, vegetables |
| Water | carries everything around | water, juice, fruit |
Two nutrients give no energy at all — vitamins and minerals. They are still essential, because without them the body cannot use the others properly.
Roughage is not digested, and that is exactly the point. It gives the food bulk so it can move smoothly through the gut, preventing constipation.
Missing one nutrient for long enough causes a specific illness — and each has a specific cure.
🩺 Missing what, and what happens
| Missing | Disease | Sign |
|---|---|---|
| Vitamin A | night blindness | cannot see well in dim light |
| Vitamin B1 | beriberi | weak muscles, poor nerves |
| Vitamin C | scurvy | bleeding gums, slow healing |
| Vitamin D | rickets | soft, bent bones |
| Iron | anaemia | tiredness, pale skin |
| Iodine | goitre | swelling of the thyroid in the neck |
| Calcium | weak bones and teeth | bones break easily |
| Protein | kwashiorkor, marasmus | stunted growth |
Two that are easy to confuse: scurvy comes from a lack of vitamin C (think C for citrus), and rickets from a lack of vitamin D, which your skin makes in sunlight. Iodised salt was introduced in India specifically to prevent goitre.
The body defends itself. Good habits simply give that defence a fair chance.
Two kinds of immunity. Innate immunity you are born with — skin, tears, stomach acid stop most germs. Acquired immunity is built after an infection or a vaccination, when the body learns to make specific antibodies.
🛡️ Habits that actually matter
| Habit | Why |
|---|---|
| Wash hands before eating | most stomach illness travels from hand to mouth |
| Drink safe water | prevents cholera, typhoid and jaundice |
| Sleep 8–9 hours | the body repairs itself during sleep |
| Exercise daily | strengthens heart, lungs and muscles |
| Eat a balanced diet | no single food has everything |
Tobacco and alcohol harm every system they touch — lungs, liver, heart and brain. There is no safe amount for a young person, and the damage builds silently for years before it shows.
12 questions on nutrition, deficiency diseases and immunity. 🍀
