Complete Biology notes on Nutrition and Health for BPSC and Other Competitive Exams in 2025

Complete Biology notes on Nutrition and Health for BPSC and Other Competitive Exams in 2025

General Science- 19 (Biology)

Nutrition and Health

Nutrition and health are intrinsically linked. Proper nutrition is the cornerstone of good health, playing a vital role in growth, development, disease prevention, and overall well-being.

1. Introduction to Nutrition and Health

• Nutrition: The process by which living organisms obtain food and utilize it for growth, energy, repair, and maintenance of life processes It involves ingestion, digestion, absorption, assimilation, and egestion.
• Health: As defined by the World Health Organization (WHO), health is “a state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity.”
• Interrelationship: A balanced diet provides all the essential nutrients in adequate amounts, which is crucial for maintaining good health, strong immunity, and preventing various diseases. Conversely, poor nutrition can lead to malnutrition and a host of health problems.

2. Components of a Balanced Diet / Essential Nutrients

A balanced diet provides all the necessary nutrients in the right proportions to meet the body’s needs. Nutrients are broadly classified into macronutrients (needed in large amounts) and micronutrients (needed in small amounts).

A. Macronutrients:

1. Carbohydrates (Energy-giving food):
   • Sources: Grains (wheat, rice, maize, jowar, bajra), potatoes, fruits (banana, mango), sugar, honey, jaggery.
   • Functions: Primary source of energy for the body’s activities and brain function.
   • Types:
     • Simple Carbohydrates (Sugars): Glucose, fructose, sucrose (quick energy).
     • Complex Carbohydrates (Starches, Fiber): Polysaccharides (provide sustained energy and fiber).
2. Proteins (Body-building food):
   • Sources: Pulses (dal), legumes, nuts, milk, cheese, eggs, meat, fish, poultry, soybeans.
   • Functions: Essential for growth, repair of body tissues, formation of enzymes, hormones, antibodies, and hemoglobin.
   • Amino Acids: Proteins are made of amino acids.
     • Essential Amino Acids: Cannot be synthesized by the body and must be obtained from diet.
     • Non-essential Amino Acids: Can be synthesized by the body.
3. Fats (Lipids – Concentrated energy source):
   • Sources: Oils (vegetable oils, ghee, butter), nuts, seeds, cheese, meat, fatty fish.
   • Functions: Provide concentrated energy, insulate the body, protect organs, transport fat-soluble vitamins (A, D, E, K).
   • Types:
     • Saturated Fats: (Animal fats, butter, coconut oil, palm oil) – generally considered less healthy in excess.
     • Unsaturated Fats: (Vegetable oils like olive oil, sunflower oil, nuts, avocados) – generally considered healthier.
     • Trans Fats: (Processed foods, fried snacks) – harmful to health.

B. Micronutrients:

1. Vitamins (Protective food): Organic compounds required in small quantities for various metabolic functions, growth, and development.
   • Fat-soluble Vitamins: Stored in the body’s fatty tissues.
     • Vitamin A (Retinol):Sources: Carrots, leafy greens, milk, eggs, liver.
     • Functions: Good vision (especially in dim light), healthy skin, immune function.
     • Deficiency: Night blindness, Xerophthalmia.

1. Vitamin D (Calciferol):
   • Sources: Sunlight exposure (synthesized in skin), fatty fish, fortified milk.
   • Functions: Calcium absorption, bone health.
   • Deficiency: Rickets (in children), Osteomalacia (in adults).
2. Vitamin E (Tocopherol):
   • Sources: Vegetable oils, nuts, seeds, leafy greens.
   • Functions: Antioxidant, protects cells from damage.
   • Deficiency: Rare, nerve damage.

1. Vitamin K:
   • Sources: Leafy greens, synthesized by gut bacteria.
   • Functions: Blood clotting.
   • Deficiency: Bleeding disorders.

1. Water-soluble Vitamins: Not stored in the body and need to be regularly supplied.
   • Vitamin B Complex: Group of 8 vitamins (B1, B2, B3, B5, B6, B7, B9, B12).
   • Sources: Whole grains, meat, dairy, leafy greens.
   • Functions: Energy metabolism, nerve function, blood cell formation.
     1. B1 (Thiamine): Deficiency: Beriberi.
     1. B3 (Niacin): Deficiency: Pellagra.
     1. B9 (Folic Acid/Folate): Functions: Cell division, DNA synthesis, crucial during pregnancy.
   • Deficiency: Anemia, neural tube defects.
     1. B12 (Cobalamin):
   • Functions: Red blood cell formation, nerve function.
   • Deficiency: Pernicious anemia.
2. Vitamin C (Ascorbic Acid):
   • Sources: Citrus fruits (orange, lemon), amla, guava, tomatoes.
   • Functions: Antioxidant, collagen formation, immune function, iron absorption.
   • Deficiency: Scurvy (bleeding gums, joint pain).

2. Minerals (Protective food): Inorganic elements required for various body functions, bone and teeth formation, and fluid balance.
   • Calcium (Ca):
   • Sources: Milk, dairy products, leafy greens.
   • Functions: Bone and teeth formation, muscle contraction, nerve function, blood clotting. Deficiency: Osteoporosis, rickets.
   • Iron (Fe):
   • Sources: Red meat, leafy greens, pulses, fortified cereals.
   • Functions: Component of hemoglobin (oxygen transport).
   • Deficiency: Anemia (iron deficiency anemia).
   • Iodine (I):
   • Sources: Iodized salt, seafood.
   • Functions: Thyroid hormone production (regulates metabolism).
   • Deficiency: Goiter, cretinism (in children).
   • Sodium (Na) & Potassium (K):
   • Sources: Salt (sodium), fruits, vegetables (potassium).
   • Functions: Fluid balance, nerve impulses, muscle function.
   • Phosphorus (P):
   • Sources: Dairy, meat, nuts.
   • Functions: Bone and teeth formation, energy metabolism.
   • Zinc (Zn): Sources: Meat, nuts, legumes.
   • Functions: Immune function, wound healing, growth.
3. Water:
   • Functions: Solvent for biochemical reactions, transports nutrients and wastes, regulates body temperature, lubricates joints, aids digestion.
   • Requirement: Essential for survival, humans need to drink adequate water daily.
4. Dietary Fiber (Roughage):
   • Sources: Whole grains, fruits, vegetables, legumes.
   • Functions: Aids digestion, prevents constipation, helps maintain bowel health, helps control blood sugar and cholesterol levels. It is not digested by the human body but provides bulk to food.

3. Malnutrition and Health Issues Related to Nutrition

Malnutrition: Refers to imbalances in a person’s intake of energy and/or nutrients. It includes both under-nutrition and over-nutrition.

A. Under-nutrition:

Results from insufficient intake of energy and/or nutrients.

• Protein-Energy Malnutrition (PEM):
  • Kwashiorkor: Primarily due to protein deficiency, often seen in children after weaning. Symptoms include swollen belly (edema), stunted growth, changes in hair and skin.
  • Marasmus: Severe deficiency of both protein and calories. Symptoms include severe wasting of muscle and fat, extreme thinness, stunted growth, weakened immune system.
• Micronutrient Deficiencies:
  • Anemia (Iron Deficiency Anemia): Lack of sufficient iron leading to reduced oxygen-carrying capacity of blood. Symptoms: fatigue, weakness, pale skin.
  • Vitamin A Deficiency (VAD): Leading cause of preventable childhood blindness (e.g., Night Blindness, Xerophthalmia).
  • Iodine Deficiency Disorders (IDDs): Goiter, and severe mental and physical impairment (cretinism) if deficiency occurs during fetal development.
  • Vitamin D Deficiency: Rickets (soft, weak bones in children), Osteomalacia (in adults).

B. Over-nutrition:

Results from excessive intake of energy and/or nutrients.

• Obesity: Excessive accumulation of body fat, posing health risks.
• Related Health Issues: Over-nutrition significantly increases the risk of Non-Communicable Diseases (NCDs) such as:
  • Type 2 Diabetes: Often linked to obesity and unhealthy diet.
  • Cardiovascular Diseases (CVDs): Hypertension (high blood pressure), heart attacks, strokes, linked to high intake of unhealthy fats, cholesterol, and sodium.
  • Certain Cancers.
  • Joint problems: Due to excessive weight.

4. Government Programs/Initiatives related to Nutrition and Health

The Indian government, including states like Bihar, has implemented various schemes to address nutrition and health challenges.

1. Integrated Child Development Services (ICDS) Scheme (Launched 1975):
   • Purpose: To improve the nutritional and health status of children (0-6 years), pregnant women, and lactating mothers.
   • Services: Supplementary nutrition, pre-school non-formal education, nutrition & health education, immunization, health check-up, referral services. Delivered through Anganwadi Centres.
2. PM POSHAN Scheme (Pradhan Mantri Poshan Shakti Nirman) / Formerly Mid-Day Meal Scheme (MDMS):
   • Purpose: To enhance the nutritional status of schoolchildren (Class I-VIII) and encourage school attendance.
   • Benefit: Provides hot cooked meals to children in government and government-aided schools.
3. National Health Mission (NHM) (Launched 2013, by subsuming NRHM & NUHM):
   • Purpose: To achieve universal access to equitable, affordable, and quality healthcare services.
   • Focus: Strengthening health systems, improving RMNCH+A (Reproductive, Maternal, Newborn, Child, Adolescent Health) services, and controlling communicable and non-communicable diseases.
4. Ayushman Bharat (Pradhan Mantri Jan Arogya Yojana – PMJAY) (Launched 2018):
   • Purpose: Provides health insurance coverage up to ₹5 lakh per family per year for secondary and tertiary care hospitalization to over 10 crore poor and vulnerable families.
5. Janani Shishu Suraksha Karyakram (JSSK) (Launched 2011):
   • Purpose: To eliminate out-of-pocket expenses for pregnant women and sick infants accessing public health institutions for delivery and treatment.
6. Food Safety and Standards Authority of India (FSSAI):
   • Role: An autonomous statutory body established under the Ministry of Health & Family Welfare. Responsible for protecting and promoting public health through the regulation and supervision of food safety.

Practice Questions

1. Which of the following is considered the primary energy-giving nutrient for the human body?
   • A) Proteins
   • B) Fats
   • C) Carbohydrates
   • D) Vitamins
   • Rationale: Carbohydrates are the body’s preferred and most readily available source of energy.
2. Scurvy, a disease characterized by bleeding gums and joint pain, is caused by the deficiency of which vitamin?
   • A) Vitamin A
   • B) Vitamin D
   • C) Vitamin B1
   • D) Vitamin C
   • Rationale: Vitamin C (Ascorbic Acid) deficiency leads to scurvy.
3. Night blindness is a common symptom of the deficiency of which fat-soluble vitamin?
   • A) Vitamin D
   • B) Vitamin E
   • C) Vitamin K
   • D) Vitamin A
   • Rationale: Vitamin A is crucial for good vision, and its deficiency causes night blindness.
4. Goiter is a health condition associated with the deficiency of which mineral?
   • A) Iron
   • B) Calcium
   • C) Zinc
   • D) Iodine
   • Rationale: Insufficient iodine intake can lead to an enlarged thyroid gland (goiter).
5. Which macronutrient is essential for the growth and repair of body tissues and the formation of enzymes and hormones?
   • A) Carbohydrates
   • B) Fats
   • C) Proteins
   • D) Water
   • Rationale: Proteins are often called the “building blocks” of the body due to their role in growth and repair.

6. Kwashiorkor is a form of malnutrition primarily caused by the deficiency of:
   • A) Carbohydrates
   • B) Fats
   • C) Proteins
   • D) Vitamins
   • Rationale: Kwashiorkor is characterized by protein deficiency, leading to edema and growth failure.
7. Excessive body fat accumulation, often a result of over-nutrition, is medically termed as:
   • A) Marasmus
   • B) Anemia
   • C) Goiter
   • D) Obesity
   • Rationale: Obesity is the medical term for excessive body fat accumulation.
8. Which of the following diseases is directly associated with an unhealthy diet rich in saturated fats and high cholesterol?
   • A) Malaria
   • B) Tuberculosis
   • C) Cardiovascular diseases
   • D) Scurvy
   • Rationale: High intake of unhealthy fats and cholesterol significantly contributes to cardiovascular diseases.

9. The Integrated Child Development Services (ICDS) Scheme primarily aims to improve the nutritional and health status of which group?
   • A) Adolescent boys
   • B) Elderly citizens
   • C) Children (0-6 years), pregnant women, and lactating mothers
   • D) Schoolchildren (Class IX-XII)
   • Rationale: ICDS specifically targets the nutritional and health needs of young children and mothers.
10. The PM POSHAN scheme (formerly Mid-Day Meal Scheme) in India is designed to enhance the nutritional status of:
    • A) Pregnant women
    • B) Schoolchildren
    • C) Adult laborers
    • D) Rural women
    • Rationale: PM POSHAN provides cooked meals to schoolchildren to address hunger and improve nutrition.
11. Ayushman Bharat (PMJAY) provides health insurance coverage primarily for:
    • A) Out-patient consultations
    • B) Secondary and tertiary care hospitalization for poor families
    • C) Only communicable disease treatment
    • D) All citizens, regardless of income
    • Rationale: PMJAY is a large-scale health insurance scheme for hospitalization expenses, targeting vulnerable families.