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Questions and Answers
What is a consequence of prolonged excessive intake of vitamin D?
Which vitamin is primarily acquired from plant sources and is known as an antioxidant?
Which of the following is a vitamin K-dependent clotting factor?
What condition is primarily associated with vitamin D deficiency in children?
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What type of vitamin K is synthesized by intestinal flora?
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Which of the following foods is a rich source of vitamin E?
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How does vitamin K function in the body?
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What characteristic of vitamins indicates that they do not provide energy?
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Vitamin D is crucial for the metabolism of which of the following minerals?
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Which of the following is a major function of Vitamin D?
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What consequence is directly linked to a deficiency in Vitamin A?
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In what form can Vitamin D be synthesized in the body?
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What is true about fat-soluble vitamins?
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Which vitamin is primarily responsible for blood clotting?
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What impact does heat have on the nutritional value of vitamins?
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What is a primary source of carotenoids, which are major sources of Vitamin A?
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Which reaction involves the reduction of NAD+ to NADH?
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Which condition is associated with niacin deficiency?
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What is a function of NADP+/NADPH?
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What are the symptoms of niacin deficiency collectively known as?
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What components make up pantothenic acid?
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What role does Vitamin K primarily serve in the body?
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Which condition is NOT a reason for Vitamin K supplementation?
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Which vitamin is involved in the conversion of pyruvate to Acetyl-CoA?
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What deficiency condition is associated with a lack of Thiamine?
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Which of the following best describes the role of Vitamin B2 (Riboflavin) in the body?
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What is one common cause of Thiamine deficiency?
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Which food source is the least likely to be high in Vitamin B2 (Riboflavin)?
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What term is used to describe the condition resulting from Thiamine deficiency characterized by neurological issues?
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What is the central atom in the corrin nucleus of B12/Cobalamin?
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What role does methylcobalamin play in methionine synthesis?
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What does the methyl-folate trap hypothesis describe?
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Which vitamin B12-dependent reaction is catalyzed by methylmalonyl CoA mutase?
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What is a common deficiency disorder associated with vitamin B12 deficiency?
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Which condition can lead to vitamin B12 deficiency due to malabsorption?
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Why is the synthesis of vitamin C significant in humans?
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Which symptom is associated with vitamin B12 deficiency?
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Which animals are known to be unable to synthesize vitamin C?
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What is one key role of vitamin C in the body?
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Which reaction does vitamin C NOT participate in?
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What condition arises from a deficiency in vitamin C?
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Which of the following is an antioxidant property of vitamin C?
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How does vitamin C aid in iron absorption?
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What is the significance of hydroxylation reactions involving vitamin C?
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Which of the following statements accurately describes vitamin C's antioxidant activity?
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Study Notes
Micronutrients (Vitamins & Minerals)
- Micronutrients are organic (carbon) compounds needed for normal function, growth, and maintenance.
- Vitamins act as coenzymes, meaning they don't do anything on their own.
- Vitamins are not a source of calories.
- Nutritional value can be lost due to light, heat, oxidation, bacteria, enzymes, and insects.
The Nature of Vitamins
- Various factors affect the nutritional value of vitamins, including light, heat, oxidation, bacteria, enzymes, and insects.
- The effect of packaging on nutrient loss in milk is illustrated by a graph.
Fat Soluble Vitamins
- Fat-soluble vitamins are stored in the liver and fatty tissues.
- Daily intake is not required.
- Deficiency occurs only after prolonged deprivation.
- Excessive intake can be toxic.
Fat Soluble Vitamins (Specific types)
- Vitamin A: involved in reproduction, mucosal integrity, vision, and antioxidant roles.
- Vitamin D: obtained from diet or synthesized on the skin (by using sunlight) from cholesterol, regulating Ca:P ratios in the body.
- Vitamin E: involved as antioxidant roles.
- Vitamin K: contributes to blood clotting.
Vitamin A
- Carotinoids are major sources of Vitamin A, and it's stored in the liver.
- Has antioxidant roles, involved in cell division, mucosal integrity, and vision/sight.
- Deficiency states are characterized by hyperkeratosis of the skin and night blindness.
Vitamin D
- Also known as calciferol/calcitriol, playing a role in calcium absorption/reabsorption.
- Stored in the body.
- Synthesized in the body (with sunlight from cholesterol).
- Sources include plant-and animal-based foods like fish oils, salmon, animal livers, eggs, butter, cereals, and fortified milk.
- Its main function is maintaining Ca+2 and P- levels (normal calcification of bones & teeth) in the body.
Vitamin D Synthesis
- Shows the process of Vitamin D synthesis in the body, with different enzymes involved in different stages.
Vit.D/Calcitriol and Ca+2/P metabolism
- Diagram showing the metabolism of calcium and vitamin D.
- Shows how PTH and calcitriol influence calcium levels in the body and in different organs.
Vit. D Deficiency
- Children and elderly are at risk for issues like osteomalacia/osteoporosis due to lack of enough sunlight.
- 'Rickets' is caused by a lack of sunlight or vitamin D, also linked to calcium intake problems in children.
- Vitamin D is also linked to extraskeletal roles.
Vitamin D: Toxicity
- Long-term consumption of excessive amounts causes toxicity.
- Symptoms include hypertension, weakness, fatigue, headaches, and GI tract effects and CNS effects.
Vitamin E (α-tocopherol)
- A fat-soluble vitamin.
- Sources include dietary plant sources (fruits, grains, cereals, vegetables, oils, wheat germ) and animal sources (eggs, chicken, meats, fish).
- Believed to act as an antioxidant.
Vitamin K
- A fat-soluble vitamin with three types (K1, K2, K3).
- Dietary sources include green leafy vegetables (cabbage, spinach), meats, and milk.
- Vitamin K2 is synthesized by intestinal flora.
- Essential for the synthesis of blood clotting factors (II, VII, IX, X).
Vitamin K in Blood Clotting
- Vitamin K is involved in the carboxylation of glutamyl residues that creates y-carboxyglutamate (by y-glutamyl carboxylase) on 4 major proteins.
- This is required for blood coagulation (factor II or prothrombin, VII, IX, and X are examples.)
Vitamin K Indications
- Dietary supplementation for deficiency states (rare).
- Treatment during antibiotic therapy.
- Necessary for newborns.
- Conditions with malabsorption.
- Often used to reverse the effects of anticoagulants (such as warfarin, heparin).
Water Soluble Vitamins
- Can dissolve in water.
- Excessive amounts are excreted in the urine, not stored in the body.
- Most (except Vitamin C) are B-complex vitamins, acting as co-enzymes.
- Includes Vitamins B1 through B12.
Vitamin B1-Thiamine
- Involved in carbohydrate metabolism in metabolic pathways including Kreb cycle as TPP; pyruvate conversion to Acetyl-CoA.
- Functions in energy transformation (TDP/TPP).
- Plays a role in the pyruvate dehydrogenase (PPD), the a-ketoglutarate dehydrogenase complex, and the branched chain a-keto acid dehydrogenase complex.
- Maintains integrity of peripheral nervous system, CVS and GI tracts.
Deficiency of Thiamine
- Deficiency causes a disease called beri-beri.
- Characterized by brain lesions, polyneuropathy of peripheral nerves, serous effusions, and cardiac anatomic changes.
Causes of Thiamine Deficiencies
- Poor diet; extended fever, hyperthyroidism, liver diseases, and alcoholism.
- Malabsorption conditions.
- Pregnancy and breast-feeding.
Vit B2 - Riboflavin
- Water soluble vitamin.
- Food sources include leafy green vegetables, eggs, nuts, and meat.
Vit B2 - Riboflavin (function)
- Two co-enzyme forms: FMN & FAD.
- Involved in energy metabolism (various oxidation-reduction reactions).
Functions of Vitamins B2
- Involved in oxidative decarboxylation of pyruvate & alpha-ketoglutarate.
- Succinate dehydrogenase is a FAD flavoprotein.
- In fatty acid oxidation [fatty acyl CoA dehydrogenase].
- A coenzyme for an oxidase such as xanthine oxidase.
- Vit. B6 metabolism: pyridoxine phosphate oxidase converts pyridoxamine phosphate and pyridoxine phosphate to pyridoxal phosphate.
B2 Deficiency
- Alcoholism is a major cause.
- Other conditions include intestinal malabsorption, long-term infections, liver disease, and malignancy/probenecid therapy.
VIT B2 Indications
- Dietary supplement.
- Treatment of B2 deficiency.
- Microcytic anemia; Acne and migraine headaches.
- Other uses.
Niacin (B3)
- Obtained from meats, beans, liver, yeast, and wheat.
- The body can create niacin from tryptophan, an amino acid.
- Roles include energy metabolism (glycogenolysis, lipid/protein metabolism, tissue respiration), and purine metabolism.
- Supports nervous and digestive system health and promotes healthy skin.
Niacin (B3) Coenzyme forms
- Two coenzyme forms: NAD+ and NADP+.
- Important for energy metabolism.
Niacin (B3) Functions
- About 200 enzymes, primarily dehydrogenases, require either NAD+ or NADP+.
- Involved in various oxidative reactions, including glycolysis, oxidative decarboxylation of pyruvate, oxidation of acetyl CoA in the TCA cycle, beta-oxidation of fatty acids, and oxidation of ethanol.
- Involved in reductive biosyntheses like fatty acid synthesis, and cholesterol and steroid hormone synthesis.
Niacin (B3) Deficiency
- Mental symptoms (various psychotic symptoms).
- Neurologic symptoms (neurasthenic syndrome).
- Cutaneous effects (crusting, erythema).
- Mucous membrane lesions (oral, vaginal, and urethral).
- GI-tract issues (diarrhea or bloody diarrhea).
Niacin (B3) Deficiency Disorder/States
- Like thiamine, deficiency was discovered through the condition pellagra in humans and a similar condition "black tongue" in dogs.
- Characterized by dermatitis, dementia, and diarrhea (Three Ds). Death (4th D).
Pantothenic acid-VitB5 (Part of CoA)
- Consists of beta-alanine and pantoic acid linked by a peptide bond/amide linkage.
- Part of a coenzyme (CoA) essential for various cellular reactions.
CoA Structure
- Contains phosphopantetheine, beta-alanine, pantoic acid, and 3',5'-bisphosphate, serving various cellular functions.
CoA functions
- Forms thio esters with carboxylic acids.
- Involved in transferring acetyl or acyl groups (typically 2-13 carbons).
- Involved in carbohydrate metabolism.
- Involved in fatty acid synthesis, ketone body synthesis, and other cellular reactions.
Vit B6 (Pyridoxine)
- Sources include whole grains, wheat germ, nuts, yeast, and fish/organ meats.
- Coenzyme form is PLP (pyridoxal phosphate).
- Involved in >100 reactions related to amino acid metabolism (transamination reactions) and fatty acid metabolism.
- Involved in nerve, skin, and mucous membrane integrity.
- Essential for many metabolic functions.
Biotin - Vit B7
- Involved in energy metabolism (carboxylation reactions).
- Synthesized by bacteria in the GI tract.
- Plays a crucial role in gluconeogenesis, fatty acid metabolism, and the breakdown of amino acids.
Biotin-dependent Enzymes
- Enzyme examples include pyruvate carboxylase, acetyl-CoA carboxylase, propionyl-CoA carboxylase, and beta-methylcrotonyl CoA carboxylase, all vital in several biochemical processes.
Folate - Folic acid - Vit B9
- Composed of three distinct parts.
- Coenzyme form is THF
- Crucial for metabolism and DNA synthesis.
- Discovered in connection with megaloblastic anemia.
Folate Functions and Mechanism of Action (MoA)
- Functions as a coenzyme in both mitochondria and cytoplasm.
- Accepts one-carbon groups in amino acid synthesis, DNA synthesis, and purine/pyrimidine synthesis.
- Derivatives participate in various reactions, most oxidized are formyls and most reduced is 5-methyl THF.
Folate in DNA (Purine & Pyrimidine) Synthesis
- Needed in purine synthesis (adenine and guanine ring formation).
- Involved in Pyrimidine synthesis, converting dUMP to dTMP with thymidylate synthetase using 5,10-methylene THF.
- Important for regenerating 5,10-methylene THF and using dihydrofolate reductase (DHFR) with NADPH.
Folate Deficiency
- Causes megaloblastic anemia, characterized by increased mean cell volume (MCV) of white blood cells (neutrophils) and hypersegmentation with abnormal cell division.
Vitamin B12 - Cyanocobalamine
- Contains the corrin nucleus (macrocyclic ring of 4 reduced pyrrole rings).
- Has a cobalt (Co) atom in the center.
- Nucleotide 5,6-dimethylbenzimidazole attached to Co.
Vitamin B12 Functions and Mechanism of Action
- Needed in methionine synthesis/regeneration, with coenzyme methylcobalamin.
- Cobalamin bound to the methionine synthase picks up the methyl group from 5-methyl tetrahydrofolate (THF).
- Forming methylcobalamin bound to methionine synthase & THF
Vitamin B12 MoA
- Formation of 5-methyl THF is irreversible, therefore, vitamin B12 deficiency traps body folate in the 5-methyl form (methyl-folate trap hypothesis).
- Explains synergism between folate and vitamin B12.
- Crucial in the synthesis of DNA, RNA, and important for nerve fiber maintenance and growth.
Vitamin B12 (Coenzyme) Deficiency
- May cause issues with neurologic, hematologic organs, resulting from malabsorption.
- Potential causes include Pernicious anemia.
- Issues with the formation of red blood cells.
- Potential related causes including Atrophic gastritis and gasterectomy.
- Increased use of medications for GERD.
Vitamin C (Ascorbic Acid)
- Humans cannot synthesize it.
- Other animals like primates, guinea pigs, and some birds lack the ability to make it.
- Lack of gulonolactone oxidase prevents its synthesis.
Vitamin C Functions and Mechanism of Action
- Important in oxidation-reduction reactions (antioxidant activity).
- Required in various metabolic activities and can help in collagen synthesis, maintenance of bone, teeth, capillaries, and connective tissue.
- Involved in carnitine and tyrosine synthesis.
- Helps in folic acid metabolism and erythropoiesis.
- Enhances iron (Fe+2) absorption; helps with lipid synthesis and synthesis of proteins, steroids.
- Essential in resistance to infections.
Vitamin C Deficiency
- Leads to scurvy (vitamin C concentration drops low).
- Symptoms include bleeding gums, skin discolorations, sublingual hemorrhages, easy bruising (petechiae, ecchymoses, purpurae).
- Impaired wound/fracture healing, joint pain, and decaying teeth.
- Hyperkeratosis of hair follicles.
- Often due to impaired hydroxyproline & hydroxylysine synthesis.
Minerals
- Are inorganic elements or salts, acting as cofactors for enzymes and other organic molecules.
- Crucial in body functions, including regulating bodily functions and supporting many body structures.
- Electrolytes help maintain fluid balance.
Macrominerals
- Include sodium (Na+), Potassium (K+), Chloride (Cl-), Calcium (Ca+2), and Phosphorus (P), Magnesium (Mg+2).
Microminerals/Trace elements
- Include iron (Fe+2), iodine (I), manganese (Mn+2), zinc (Zn+2), copper (Cu+2), cobalt (Co+2), selenium (Se), and others.
Calcium (Ca+2)
- Most abundant mineral in the body.
- Major components in bones and teeth, usually at 99%.
- Important for various bodily functions and processes, including maintaining intra-/extracellular fluids.
- Sources include dairy products (especially cheese and yogurt), selected seafoods (salmon and sardines), some vegetables (broccoli, cauliflower, kale), legumes (tofu and dried fruits), but some meats, grain, nuts, and vegetables are poor sources because they contain high amounts of oxalic acids.
Calcium Absorption & Transport
- Shows the process of calcium absorption and transport into and out of cells.
- Shows how electrolytes, phytate, and oxalates influence calcium absorption; various substances that either enhance or inhibit absorption and excretion.
Calcium Regulation
- Diagram showing how calcium levels in the blood are tightly regulated both intracellularly and extracellularly.
- Shows how hormones like PTH and calcitriol are important.
Calcium Flow Regulation
- Diagram showing the flow of calcium and its regulation by various organs such as the bone, intestines, and kidneys.
Calcium Function
- Essential for structure; helps form the body's mineralized bone in structural support for nearly 99% of total body calcium content.
- Crucial in nervous system maintenance and muscular functionality.
- Catalyst in various enzymatic functions.
Calcium Deficiency
- Called hypocalcemia.
- Factors include inadequate calcium intake, poor absorption, excessive losses, and combinations.
- Symptoms can include tetany (intermittent muscle contractions) especially in the arms and legs.
- In adults, it can lead to osteoporosis (loss of bone mass, protein matrix, and bone minerals).
- In children, it causes rickets.
Phosphorus (P)
- Second most plentiful mineral in the body.
- Most of the phosphorus is stored in skeletal tissue, with the rest in the blood and fluids and in soft tissues like muscle.
Phosphorus Functions & Mechanisms of Action
- Important in bone mineralization (calcium phosphate).
- Involved in energy transfer and storage (ATP, creatinine, UDP-glucose).
- Vital for nucleic acid formation (DNA and RNA).
- Involved in cell membrane structure (phospholipids) and acid-base balance (intracellular phosphate buffer).
- Important in O2 Availability (synthesis of 2,3-diphosphoglycerate).
Magnesium (Mg+2)
- 4th most abundant cation in the body.
- Intracellularly, it's only second in abundance to potassium.
- About 55-60% is associated with bone.
- About 20-25% is in soft tissues, and 1% is in extracellular fluids.
Magnesium Sources
- Foods including nuts, legumes, sunflower seeds, flax seeds, whole-grain cereals (oats and barley), and beverages like coffee, tea, and cocoa.
- Also from spices, seafoods, and green leafy vegetables (spinach).
- Milk and yogurt provide Mg (30-40 mg/cup).
- Minor sources include chocolate, molasses, corn, peas, carrots, brown rice, and parsley.
Magnesium Absorption & Transport
- Shows process of how Mg+2 is absorbed and transported across a cell's membrane showing the role of various proteins and factors
Factors Influencing Magnesium Absorption
- Listing various substances that can either enhance or inhibit magnesium absorption.
Magnesium Functions & MoA
- Roughly 55-60% of magnesium is found with bone, often as magnesium hydroxide and magnesium-phosphate.
- Rest is in organs including the liver and kidneys; about 25% of Mg+2 is found in muscle.
- Important for over 300 enzyme reactions as a structural cofactor or allosteric activator of enzyme activity.
Protein Kinases
- Involved in transferring y-phosphate from ATP to substrates (E.g., HK, PFK) using Magnesium (Mg+2)
Magnesium's Role in the Body
- Involved in processes like glycolysis and the TCA cycle, and in the generation of hexose monophosphate shunt, synthesis of creatine phosphate, beta-oxidation, etc.
Magnesium Deficiency
- Hypomagnesemia.
- Can lead to numerous biochemical and symptomatic issues.
- Symptoms can involve nerve and muscle function changes (weakness, spasms, tremors).
- Leads to hyper excitability.
- May result in damages in brain.
Sodium (Na+)
- Most abundant cation, often found on the surface of bone crystals (30%).
- Found in excess in extracellular fluid (ECF).
- Mostly found in plasma, nerve, and muscle cells.
Sodium Sources
- Primary source is through salt (sodium chloride/NaCl).
- Approximately 2300 mg/2.3 grams of sodium chloride per teaspoon.
Sodium Intake & Assessment
- The National Research Council recommends an adequate intake of 2300 mg (65 mmol) of chloride daily.
- Serum chloride concentration (101-111 mEq/L) is used to assess the body's chloride levels.
- Methods include ion-selective electrode potentiometry and coulometric titration.
Sodium Functions
- Important in fluid balance (Na+, K+, and Cl-).
- Crucial in nerve transmission and muscle contraction by involvement of a Na+/K+ ATPase pump.
Sodium Deficiency/HypoNa
- Primarily arises from excessive sweating or problems with the GIT.
- Symptoms include muscle cramps, nausea, vomiting, dizziness, shock, and coma.
Potassium (K+)
- Major intracellular cation.
- About 95-98% of the body's potassium is inside the body cells.
Potassium Sources
- Found in foods with high potassium content.
Potassium Absorption & Transport
- Absorbed in the small intestine through diffusion or a K+/H+ ATPase pump.
- Absorption may involve active transport into non-intestinal cells.
Potassium Functions
- Contractility of muscles (smooth, skeletal, and cardiac).
- Excitability of nerve tissue.
- Electrolyte and pH balance.
Potassium Deficiency/Toxicity
- Hyperkalemia (high serum potassium) - toxic.
- Causes of hyperkalemia include several cardiac arrhythmias and cardiac arrest.
- Hypokalemia (low serum K+) - not from dietary deficiency.
- Symptoms include several cardiac arrhythmias, muscular weakness, nervous irritability, hypercalciuria, glucose intolerance, and mental disorientation, which may result from severe vomiting/diarrhea or with use of diuretic medications.
Chloride (Cl-)
- Most plentiful anion found in the ECF (extracellular fluid).
- Its negative charges balance the positive charges of sodium ions.
- Important for maintaining electrolyte balance.
Chloride Sources
- Found in almost all foods containing sodium chloride (NaCl/table salt).
- Includes eggs, fresh meats, and seafoods.
Chloride Absorption and transport
- Absorbed in the small intestine primarily by the same processes as for Na+; Cl- transport largely depends on Na+ absorption establishment, and maintenance of electrical neutrality.
Chloride Functions
- Important part of electrolyte fluid balance.
- Involved in HCl formation by parietal cells in the stomach.
- Released by WBCs during phagocytosis.
- Acts as an exchange anion for bicarbonate in RBCs during chloride shifts.
- Important for CO2 transport.
Chloride Deficiency
- Not usually a result of dietary deficiency.
- Typically arises from problems with the GIT (Gastrointestinal Tract), such as severe diarrhea and vomiting.
- Severe symptoms include convulsions.
Adequate Intake & Assessment (Chloride)
- The National Research Council recommends a daily intake of 2300 mg (65 mmol) of chloride, equivalent to sodium.
- Serum Chloride level (101-111 mEq/L) is used in assessing body's chloride status.
- Includes methods like ion-selective electrode potentiometry and coulometric titration.
Iron (Fe)
- Abundant metal in the Earth's crust, crucial for all life.
- Flexible redox potential has been instrumental in many vital protein processes involved in oxygen transport and electron transfer.
Iron Sources
- Animal-based sources include meats, eggs, and organ meats - rich in heme iron.
- Plant-based sources include leafy vegetables, but plant sources are lower absorption-based non-heme iron.
Iron Absorption & Transport
- Hem and nonheme iron absorption takes place and is distributed throughout the circulatory system with transferrin, a glycoprotein that binds with iron (Fe+3).
- Transferrin can bind one or two Fe+3 atoms, creating holotransferrin.
- Iron is now either stored in ferritin or used in body tissues for processes like hemoglobin synthesis.
- Absorption and transportation detailed with diagram.
Iron Functions
- Essential in oxygen-carrying hemoglobin (60-70% in RBCs) and muscle myoglobin (10%).
- Crucial for various immune functions and cognitive development/performance.
Iron Deficiency Anemia
- Iron deficiency can lead to anemia, especially in pregnant women, menstruating women, and infants.
- Symptoms and conditions include anemia, impaired red blood cells/RBC production, issues with nervous system cells and intestine cells.
- This can happen from lack of iron, or milk being the single source of iron intake for several months and is common.
Pregnancy & Anemia
- Pregnant women have a significantly higher iron requirement which can also lead to higher risk of anemia and require additional iron intake.
- Other causes of anemia include folate/vitamin B12 deficiency, pernicious anemia, and thalassemias.
- Poisoning such as Lead (Pb) poisoning also plays a role.
Recommended Dietary Intake (RDI) of Iron (Fe)
- Presents the recommended level of iron consumption per age group (adults 18-50, women 14-18, 9-13, 4-8, 1-3 years, 7-12 months, and 0-6 months).
Iodine (I)
- Essential trace element, mainly located in the thyroid gland.
- Primarily involved in thyroid hormone synthesis and releasing T4 and T3.
Iodine Absorption, Transport, & Metabolism
- Iodide (I-) is absorbed quickly in the stomach & small intestine with high bioavailability, typically over 90%.
- Absorption occurs through the sodium-iodide symporter (NIS).
- Absorbed iodide from the GIT then gets transported to the bloodstream and rapidly taken up by the thyroid gland and kidneys.
Iodine Uptake & Metabolism
- The thyroperoxidase (TPO) enzyme is crucial.
- It catalyzes the organification step.
- Iodine links to tyrosine residues in thyroglobulin either as monoiodotyrosine (MIT) or diiodotyrosine (DIT).
- Deiodinase enzyme removes Iodine (i.e helps recycling of iodine) from MIT/DIT (in the thyroid and other tissues), after the action of proteases on T3/T4 at the tissue level (e.g. liver).
Iodine Functions
- Crucial for forming thyroid hormones (T4 and T3).
- Important in metabolism (various organ systems).
- Has disinfectant qualities & used in photography (silver iodide).
Iodine Deficiency and Health Impacts
- Iodine deficiency causes several problems such as goiter (enlarged thyroid gland); disorders like mental retardation, hypothyroidism, and cretinism (in infants).
Zinc
- An essential trace mineral.
- Involved in metabolic reactions related to proteins and carbohydrates.
Zinc in Wound Healing, Infections, & Immunity
- Plays a role in wound healing, supporting immune function by its involvement in T-lymphocytes, and reducing the severity of infectious diarrhea.
- Zn supplementation may improve wound healing, T-lymphocyte counts, and the immune system's ability to manage infections.
Zinc in Cell Survival & Chromosome Stability
- Involved in the movement of nutrients within cells.
- Important for maintaining cell homeostasis.
- Found primarily in the cell nucleus; affecting processes related to chromatin stability and genetic expression.
Zinc in Cognitive Development
- Involved throughout mental development and function.
- Zn supplementation in malnourished children/adults, improves cognitive function, especially memory and attention.
Zinc in Malignant Transformation
- Studies show that a link exists between zinc deficiency and cancer development.
- Possible factors including oxidative DNA damage and chromosome breaks.
- Some studies correlate a low zinc diet with higher probability of cancer, when exposed to more carcinogens subsequently.
Fluorine (F)
- Found in water and foods such as tea and seafood.
- Important in building teeth & bones, preventing tooth decay.
- Excess levels of Fluorine can cause discoloration of teeth.
Other Minerals (Copper, Sulfur, Selenium, Cobalt)
- Copper: Supports maintaining iron levels in the body and improving anemia.
- Sulfur & Selenium: Important in constructing Sulfur molecules that are necessary for the body and also for collagen synthesis.
- Cobalt: Essential in B12 and involved in RBC development.
Fortification vs Enrichment
- Fortification: Restoring nutrients lost during processing.
- Enrichment: Adding nutrients to meet a specific standard.
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Test your knowledge on the essential vitamins and their functions with this comprehensive quiz. Explore topics from vitamin D's role in the body to the sources and functions of other vital vitamins. Challenge yourself to understand the impact of vitamin deficiencies and their consequences.
