Nutrition is the foundation of good health. A proper diet ensures growth, immunity, energy production, and prevention of diseases. This article covers the basics of nutrition, balanced diet, malnutrition, food safety, nutraceuticals, and important drug–food interactions in simple, student-friendly language.
1. Basics of Nutrition
Nutrients are substances required by the body for energy, growth, repair, and regulation of body processes. They are classified into macronutrients and micronutrients.
Macronutrients
- Carbohydrates: Primary source of energy. Examples: rice, wheat, fruits, sugar.
- Proteins: Required for growth, enzyme formation, and tissue repair. Sources: pulses, milk, eggs, fish.
- Fats: Provide concentrated energy, essential fatty acids, and help absorb fat-soluble vitamins (A, D, E, K). Sources: oils, nuts, butter.
Micronutrients
- Vitamins: Essential for immunity, metabolism, skin and eye health. Example: Vitamin C, B-complex, Vitamin A.
- Minerals: Needed for bones, blood formation, nerve function. Example: calcium, iron, iodine, zinc.
2. Importance of Water and Fibre
Water accounts for 60–70% of body weight and is essential for digestion, temperature regulation, and toxin removal. Fibres help in bowel movements, prevent constipation, control blood sugar, and reduce cholesterol. Good sources include fruits, vegetables, whole grains, and legumes.
3. Balanced Diet
A balanced diet supplies all essential nutrients in correct proportions. It includes cereals, pulses, milk, fruits, vegetables, healthy fats, and adequate water.
Malnutrition and Nutrition Deficiency Diseases
- Protein-energy malnutrition: Kwashiorkor, Marasmus.
- Vitamin A deficiency: Night blindness.
- Iron deficiency: Anemia.
- Iodine deficiency: Goiter, cretinism.
- Vitamin D deficiency: Rickets, osteomalacia.
Ill Effects of Junk Foods
- High in sugar, salt, unhealthy fats, and additives.
- Causes obesity, diabetes, hypertension, and heart diseases.
- Leads to poor concentration and fatigue.
Calorific and Nutritive Values of Foods
Carbohydrates and proteins provide 4 kcal/g, while fats provide 9 kcal/g. Nutritive value depends on vitamin, mineral, and fibre content of food items.
Fortification of Foods
Food fortification means adding essential nutrients to food to prevent deficiencies. Examples include:
- Iodized salt (iodine)
- Fortified milk (vitamin D, calcium)
- Fortified wheat flour (iron, folic acid)
4. Food Safety
Ensuring food is safe, hygienic, and free from harmful chemicals protects public health.
Food Adulteration
Adulteration is the addition of inferior or harmful substances to food. Examples:
- Water in milk
- Artificial colours in sweets
- Chalk powder in flour
It leads to poisoning, nutrient loss, and long-term health issues.
Artificial Ripening
Substances like calcium carbide and ethylene gas are used to ripen fruits quickly. These can cause headaches, vomiting, neurological issues, and nutrient loss.
Use of Pesticides
- Pesticide residues on fruits and vegetables cause cancers, hormonal imbalance, and nerve damage.
- Washing, peeling, and cooking reduce residue levels.
Genetically Modified Foods (GM Foods)
GM foods are produced by modifying genes to improve nutrition, resistance, and yield. Examples: GM cotton, GM soybeans.
Benefits include higher productivity and pest resistance. However, concerns exist about allergies, biodiversity loss, and long-term safety.
5. Dietary Supplements, Nutraceuticals, and Food Supplements
These products support health, especially when dietary intake is insufficient.
Dietary Supplements
Products containing vitamins, minerals, herbs, amino acids, or enzymes. Used for:
- Correcting deficiencies
- Improving immunity
- Enhancing energy and metabolism
Nutraceuticals
Foods or products that provide health benefits beyond basic nutrition. Examples: omega-3 capsules, probiotics, antioxidants, herbal extracts.
Food Supplements
Used for athletes, elderly individuals, pregnant women, and those recovering from illness. They include protein powders, electrolyte solutions, and fortified drinks.
Drug–Food Interactions
Some foods can affect the absorption and action of medicines:
- Grapefruit juice: Interferes with drugs like statins and calcium channel blockers.
- Milk: Reduces absorption of tetracycline antibiotics.
- Green leafy vegetables: Reduce the effect of anticoagulants like warfarin due to high vitamin K.
- Alcohol: Dangerous with sedatives, painkillers, and anti-diabetic medicines.
