Macronutrients and Micronutrients (#1)

Page 1: Macronutrients and Micronutrients

Page 2: Outline

  • Nutrition Labelling of Food Products

  • Define and Classify Nutrients

  • The Difference Between Macronutrients and Micronutrients

  • Fats and the Classes of Fatty Acids

  • Proteins and Carbohydrates

  • Minerals and List the Functions of Different Minerals

  • Classify Vitamins and List the Functions of Important Vitamins

Page 3: Nutrition Labelling

  • Label Information:

    • Serving Size

    • Calories

    • % Daily Value (%DV)

    • Fat, Carbohydrate, and Protein Content

    • Cholesterol

    • Sodium

    • Vitamins and Minerals

  • Label Importance:

    • Determine Caloric Consumption

    • Determine Nutrition Value

    • Special Diets

      • (e.g., Diabetic or Heart Patients)

Page 4: Nutrients

  • Definition of Nutrients:

    • Substances providing nourishment necessary for growth and maintenance of life.

    • Food comprises various nutrients that significantly affect metabolism.

  • Macronutrients:

    • Required in large amounts

      • (e.g., Carbohydrates, Fats, Proteins)

    • Should be consumed in proper proportions;

      • excess can lead to diseases

    • Provide calories for energy;

      • essential for growth and metabolism

  • Micronutrients:

    • Required in small amounts

      • (e.g., Vitamins and Minerals)

    • Deficiencies can lead to critical health problems

    • Essential for enzyme and hormone production necessary for growth & development

Page 5: Broad Classification of Nutrients

  • Macronutrients

    • Carbohydrates

    • Fats

    • Proteins

    • Water

  • Micronutrients

    • Vitamins

      • Water Soluble: B and C

      • Fat Soluble: A, D, E, and K

    • Minerals

      • Macrominerals:

        • Sodium

        • Potassium

        • Calcium

        • Magnesium

        • Phosphorus

        • Chloride

      • Microminerals (Trace Elements):

        • Chromium

        • Copper

        • Fluorine

        • Iodine

        • Iron

        • Manganese

        • Molybdenum

        • Selenium

        • Zinc

Macronutrients

Page 7: Fat/Fatty Acids: Macronutrients

  • Fat (Lipid):

    • Composed of three fatty acids attached to glycerol

      • → (Triglycerides)

  • Classes of Fatty Acids:

    1. Natural Fatty Acids:

      • Saturated (no double bonds), saturated with hydrogen (12-24 carbons)

    2. Monounsaturated:

      • One double bond (cis)

        • e.g., Oleic acid

    3. Polyunsaturated Fatty Acids (PUFA):

      • Multiple double bonds (cis)

        • e.g., Linoleic acid (omega-6) & Linolenic acid (omega-3) → Essential fatty acids

Page 8: Fat/Fatty Acids

  • Hydrogenation:

    • Unsaturated fatty acids can be converted to saturated fatty acids through hydrogenation.

    • Increased unsaturation = decreased melting point.

    • Saturated fatty acids are solid;

      • Saturated = Solid

    • Unsaturated are liquids (e.g., vegetable oil)

      • Unsaturated = Liquid

Page 9: Fat/Fatty Acids

  • Stability and Health Concerns:

    • Saturated fatty acids are more stable at elevated temperatures.

    • PUFAs oxidize easily.

      • ( we can reduce concentration of PUFA’s through partial hydrogenation to improve shelf-life )

    • Partial hydrogenation improves shelf-life but can produce trans fatty acids (TFAs (bad) can increase LDL (bad cholesterol), and reduce HDL (good cholesterol)

      • —potential health risks.

        • TFA take years to be flushed from body

Page 10: Fatty Acids

  • Essential Fatty Acids:

    • Linoleic acid (ω-6, double bond 6th carbons from end of chain) from vegetable oil.

    • Linolenic acid (ω-3) from fish oil.

  • Fatty acids are a major source of stored energy.

    • Metabolized in the mitochondria to generate ATP.

    • Saturated FA contribute to cholesterol production in the liver which is a precursor for steroid hormones and vitamin D.

      • High saturated fat levels elevate LDL → potentially causing atherosclerosis.

    • PUFA help lower blood cholesterol (both LDL and HDL)

    • Unsaturated fats lower LDL without affecting HDL -healthiest fat source in diet

Page 11: Carbohydrates

  • Primary Energy Source:

    • Provides 4 calories/gram.

    • After ingestion, carbohydrates are converted to:

      • Glucose: Readily available for energy in the bloodstream.

      • Glycogen: Stored in the liver and muscle cells for later use.

    • The brain relies entirely on glucose.

  • 3 Chemical Classes of Carbohydrates:

    • Monosaccharides: Glucose, fructose

    • Disaccharides: Sucrose, lactose

    • Polysaccharides: Starch (plants), glycogen (animals), dietary fiber

Page 12: Proteins

  • Function of Proteins:

    • Provide 20 amino acids.

    • When ingested, proteins are broken down into:

      • peptides & amino acids → crucial for health.

    • Last macronutrient used for energy;

      • during starvation, muscles provide energy through muscle wasting.

    • Provide 4 calories/gram.

Page 13: Micronutrients

Page 14: Minerals

  • Definition of Minerals:

    • Inorganic elements from the earth, absorbed via plants consumed by animals and humans.

  • Importance of Minerals:

    • Vital for growth, repair, reproduction, and lactation.

    • Two major groups:

      • Macrominerals: Calcium, Sodium, Potassium, Magnesium, Phosphorus, Chloride

      • Microminerals (Trace Elements): Chromium, Copper, Fluorine, Iodine, Iron, Manganese, Molybdenum, Selenium, Zinc

    • Serve as cofactors necessary for enzyme function in the body.

Page 15: Minerals

  • Specific Mineral Functions:

    • Calcium:

      • Strengthens bones and teeth

      • Supports muscle contraction and nerve signal transmission

    • Iron:

      • Essential for oxygen transport in the body

      • Deficiency can cause fatigue and low RBC count

    • Potassium:

      • Vital for muscle and nervous system function,

      • Electrolyte used to balance fluid and proper heart health

    • Zinc:

      • Crucial for growth and development

      • Required for taste and smell

    • Sodium Chloride (NaCl):

      • Maintains acid-base balance and fluid regulation

      • Muscle and nerve function

    • Cobalt:

      • Necessary for synthesizing vitamin B12

Page 16: Minerals

  • Functions of Additional Minerals:

    • Magnesium: Supports bone health, muscle and nerve function, and immune health.

    • Manganese: Important for enzyme production and healing.

    • Copper: Aids in connective tissue formation and iron metabolism.

    • Iodine: Necessary for thyroid hormone synthesis.

    • Fluoride: Maintains bone and dental health.

    • Selenium: Essential for thyroid function and antioxidant production.

Page 17: Vitamins

  • Definition and Importance of Vitamins:

    • Group of organic compounds essential for normal growth and nutrition, required in small quantities, cannot be synthesized by the body (except for Vitamin D and K).

    • Unlike macronutrients, vitamins do not provide energy (calories).

  • Types of Vitamins:

    1. Fat Soluble: Vitamins A, D, E, K; can be stored in body; risk of hypervitaminosis.

    2. Water Soluble: B complex and vitamin C; cannot be stored; easily excreted in urine; heat labile and may be destroyed during cooking or processing.

Page 18: Vitamin A - Retinol

  • Importance:

    • Essential for vision, immunity, and development.

    • Sources: β-carotene from plants converted to active retinol in the body.

    • Retinol is found in tissues as retinyl ester, and retinal is converted back to retinol as needed.

Page 19: Vitamin A and Vision

  • Mechanism of Vision:

    • In retina, retinal forms rhodopsin with opsin; sensitive to light.

    • Light stimulation converts retinal, triggering signaling to the brain via the optic nerve for vision.

    • All-trans-retinal is converted back to 11-cis-retinal in the visual cycle.

Page 20: Vitamin D – Cholecalciferol

  • Overview:

    • Technically a steroid hormone synthesized in the body but requires sunlight; may need supplements.

    • Synthesis: Provitamin D3 is activated in skin by sunlight and stored in the liver.

    • Active Form: Calcitriol synthesized in the kidneys, vital for bone health and calcium/phosphate metabolism.

    • Extensively bound to plasma proteins, prolonging half-life.

Page 21: Vitamin E - Tocopherols

  • Definition:

    • Group of compounds called tocopherols (α, β, γ, δ)

    • Absorption requires bile acids for micelle formation.

Page 22: Vitamin E - Tocopherols

  • Functions:

    • Excellent antioxidants (especially α-tocopherol).

    • Protects PUFAs in cellular membranes from oxidative damage.

    • Hypervitaminosis is uncommon as vitamin E is excreted as more soluble metabolites.

Page 23: Vitamin K – Phylloquinone, Menaquinone and Menadione

  • Definition:

    • Named for coagulation properties (German: koagulation-vitamin).

    • Natural forms: Vitamin K1 and K2; synthetic form: Vitamin K3.

  • Functions:

    • Catalyzes synthesis of prothrombin in the liver for blood clotting; regulates synthesis of plasma clotting factors (VII, IX, X).

Page 24: Vitamin C - Ascorbic Acid

  • Properties:

    • 6-carbon organic acid, antioxidant that participates in redox reactions.

    • Rich sources: citrus fruits like lemons, oranges.

    • Enhances iron absorption and involves folic acid conversion.

Page 25: Vitamin B1 - Thiamine

  • Function and Importance:

    • Involved in carbohydrate metabolism, forms thiamine pyrophosphate (coenzyme)

    • Essential for growth and nerve health; deficiency leads to Beriberi affecting muscle function.

Page 26: Vitamin B2 (Riboflavin)

  • Function:

    • Precursor for coenzymes FMN and FAD involved in oxidation-reduction processes.

    • Requires active transport for absorption, susceptible to inhibition by certain drugs.

Page 27: Vitamin B3 – Niacin (Nicotinic Acid)

  • Properties:

    • Exists as nicotinamide in tissues, synthesized from tryptophan.

    • Forms coenzymes NAD and NADP, important for dehydrogenase reactions.

Page 28: Vitamin B5 - Pantothenic Acid

  • Function:

    • Precursor to coenzyme A; involved in multiple metabolic reactions.

    • Not absorbed directly; hydrolyzed for absorption and synthesis in cells.

Page 29: Vitamin B6 - Pyridoxine

  • Components and Role:

    • Exists as a mix of three compounds (pyridoxine, pyridoxal, and pyridoxamine).

    • Phosphate form circulates in blood; coenzyme involved in amino acid transformations.

Page 30: Vitamin B - Biotin

  • Function:

    • Acts as a coenzyme in various carboxylation reactions relevant to carbohydrate, fat, and protein metabolism.

Page 31: Vitamin B9 - Folic Acid

  • Metabolism:

    • Absorbed as folate, converted to THFA for one-carbon transfer, crucial for methionine production.

    • Regeneration of THFA depends on vitamin B12.

Page 32: Vitamin B12 - Cobalamins

  • Forms:

    • AdoB12 and MeB12 are biologically active; essential for protein and deoxyribonucleotide biosynthesis.

    • B12 binds to intrinsic factor for absorption in the stomach, enhanced by gastric conditions and pancreatobiliary function.

Page 33: Vitamin B Mnemonic

  • Mnemonic Statement:

    • "The Ronaldo n Paolo played for Biochester Football Club"

Page 34: Summary: Fat Soluble vs. Water Soluble Vitamins

  • Fat Soluble:

    • Vitamins A, D, E, K; hydrophobic; stored in body; toxicity more common; deficiency manifests slowly.

  • Water Soluble:

    • B complex and C; hydrophilic; excreted in urine; toxicity less common; deficiency manifests rapidly.

Page 35: Summary

  • Overview of nutrient types:

    • Macronutrients vs. Micronutrients

    • Classes and properties of fatty acids

    • Information on carbohydrates and proteins

    • Overview of vitamins and minerals.