Nutrients• Molecules required in diet for absorption and use by the body.• Healthy diet : balance between different types of nutrients.• Classified according to the recommended daily intake: – Micronutrients – Macronutrients
Micronutrients• Needed in extremely small amounts (less than 0.005% of body mass)• Severe consequences if absence.• Measure in mg or μg per day due to its small quantities.• Essential for the body to produce enzymes, hormones and other substances essential for health.• Vitamins and trace minerals (Fe,Cu,Zn,I and ect.)
Macronutrients• Needed in relatively large amount.• Provide energy in the body.• Build and maintain body structure.• Includes macromolecules : – Carbohydrates – Protein – Lipids – Minerals ( Na, Mg, K,Ca,P, S and Cl )
Vitamins are group of complex organic compounds present in very small quantities in food and absorbed into the body during digestion.(Not synthesized in the body)They have , but are for a healthy body and for maintaining metabolism.
Vitamins are classified into : Generally consumed along with fat-containing foods Stored in the liver and adipose (fat) tissue Not to be consumed every day. Non-polar molecules with long hydrocarbon chain or ring. Eg: Vitamins
Only stored in small amounts inside cells Transported directly into the blood Excess filtered out by kidney and excreted. Must be consumed frequently Have polar bonds and form hydrogen bonds with water. Eg: Vitamins
B.5.2: Compare the structures of (vitamin A, (vitamin D) and (vitamin C).B.5.3: Deduce whether a vitamin is or from its structure.
• Contain a .• Alternate double and single bonds.• One polar hydroxyl group• Vitamin A is , non-polar hydrocarbon chain and ring influence the solubility.• Involved in visual cycle and important for vision at low light intensity.
• A (compare to A and D)• Has fived-membered containing an oxygen.• (C=C) alkene and (C=O) carbonyl group• Contains polar hydroxyl groups that form hydrogen bond with water.• Vitamin C and cannot retained for long by body.• Cofactor in some enzyme reaction.• Important in tissue regeneration• Helps gives resistance to some disease.
hydrocarbon molecules.• Predominantly• 4 non-polar rings• One polar hydroxyl group• Chemically similar to cholesterol.• Vitamin D is , non-polar hydrocarbon chain and ring influence the solubility.• Stimulate uptake of calcium ions by cells.• Important in bones and teeth health.
• Vitamins are easily destroy by most method of food processing and storage due to the several functional group that easily oxidized ( -OH and –C=C- )• Best obtained from fresh fruits and vegetables.