🧬 Vitamins: Essential Micronutrients

Vitamins are organic compounds required in small quantities to support normal growth, metabolism, and overall health. They are classified as essential micronutrients because the human body cannot synthesize them in adequate amounts (with partial exceptions such as Vitamin D and Vitamin K). Therefore, they must be obtained through diet.

#📚 Discovery & Classification

• The term "Vitamine" was coined in 1912 by Casimir Funk, based on earlier work by Sir Frederick Gowland Hopkins.

🔹 Classification Based on Solubility

1. Fat-Soluble Vitamins

• Stored in liver and fatty tissues
• Include: A, D, E, K

2. Water-Soluble Vitamins

• Not stored significantly in the body
• Excess is excreted through urine
• Include: B-complex vitamins and Vitamin C

#🥕 1. Vitamin A (Retinol)

Vitamin A plays a crucial role in vision, immune function, and epithelial tissue maintenance.

🔹 Forms

• $A_1$: Retinol
• $A_2$: Dehydroretinol

🔹 Sources

• Carrots ($\beta$-carotene)
• Dairy products
• Green leafy vegetables

🔹 Deficiency Diseases

#☀️ 2. Vitamin D (Calciferol)

Vitamin D is known as the "Sunshine Vitamin" because it is synthesized in the skin upon exposure to sunlight.

🔹 Synthesis

🔹 Forms

• $D_2$: Ergocalciferol (plant source)
• $D_3$: Cholecalciferol (animal source)

🔹 Sources

• Fish liver oil
• Fortified orange juice
• Mushrooms

🔹 Functions

• Promotes calcium absorption
• Maintains healthy bones and teeth

🔹 Deficiency Diseases

#🌿 3. Vitamin E (Tocopherol)

Vitamin E is widely known for its antioxidant properties and role in maintaining cellular integrity.

🔹 Sources

• Avocado
• Peanuts
• Sunflower seeds
• Green vegetables

🔹 Functions

• Acts as an antioxidant
• Supports reproductive health
• Protects cell membranes from damage

🔹 Deficiency Symptoms

#📌 Summary

• Vitamins are essential micronutrients required for proper body functioning
• Classified into fat-soluble and water-soluble groups
• Vitamin A → Vision and epithelial health
• Vitamin D → Bone health and calcium regulation
• Vitamin E → Antioxidant and cell protection