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Chapter 8 Water & Minerals: The Ocean Within. A Note to My Students. Please use these lecture notes in addition to the previous lecture notes on chapter 8
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Chapter 8 Water & Minerals: The Ocean Within
A Note to My Students • Please use these lecture notes in addition to the previous lecture notes on chapter 8 • The material is the same, but has been reorganized so that you can better understand that nutrients work together to serve a similar purpose/function • I have added my own thoughts to some of the slides so that you will not miss the main points • Email me or have office hours with me if you have any further questions on the material
Understanding Minerals • Minerals • Inorganic • Not destroyed by heat, light, acidity, alkalinity • Micronutrients (needed in small amounts) • Grouped as: • Major minerals (>100 mg/day) • Trace minerals (<100 mg/day)
Minerals in Foods • Found in plant (soil) and animal (diet) foods • Found in drinking water: sodium, magnesium, fluoride • Mineral absorption limited by several factors: • GI tract length • Competing minerals (ex. megadose) • High-fiber diet contain phytates (iron, zinc, manganese, calcium) • Oxalate (calcium)
Major Minerals and Health Mineral status significantly affects health Play critical parts in hypertension and osteoporosis
Hypertension • Fluid balance (blood, sweat, tears) • Sodium, Potassium, and Chloride • In our kidney: maintain balance of electrolytes to pull water across a wall of cells from the bloodstream bladder • Hypertension: high blood pressure • Diet: • High sodium, low potassium • More salt less water removed = higher BP
Nerve Impulse Balance • Neurons send messages electrical signals using charged chemicals • Sodium (Na+): outside • Chloride (Cl-) : outside • Potassium (K+): inside • Calcium (Ca2+):out, at end of axon
Steps: • At rest: Na+ is outside, K+ is inside • Overall, electrical charge is negative inside than outside • Stimulus opens Na+ ion gates: Na+ in • Action Potential is created signal is transmitted
Nerve Impulse Balance • Transmission of a nerve impulse is rapid and self-propagating (like dominoes) • Transmission of nerve impulses depends upon a difference in charge across the cell membrane
Bone Structure Hydroxyapatite: a crystalline mineral compound of calcium and phosphorous Supplies Ca and P blood and soft tissues Bone cells Osteoblasts Osteoclasts Fluoride promotes the deposition of Ca and P in bones and teeth
Blood Calcium • Regulation of blood calcium levels • Calcitriol/Vitamin D • Parathyroid hormone • Calcitonin • Why control blood calcium? • Important for muscle contraction and nerve impulses • If too high non-responsive • If too low spasms, convulsions
Regulation of Blood Calcium (Calcitonin and Parathyroid Hormone)
Magnesium • Function • Participates in more than 300 types of enzyme-driven reactions such as energy metabolism • Cardiac and nerve function • Main Storage: Bones
Protein Shape • Sulfur helps proteins maintain their functional shapes such as skin, hair, nails • Disulfide Bridges
Trace Minerals • Trace Minerals: • Iron, Zinc, Selenium, Iodine, Copper, Manganese, Fluoride, Chromium, Molybdenum • Cofactors for enzymes • Components of hormones • Participate in many chemical reaction • Essential for: • Growth • Immune System
Brain and Nervous System • Nerve cell protection • Iron helps produce myelin sheath • Nerve cell communication: • Iron helps produce neurotransmitters
Oxygen Transport • Hemoglobin vs. Myoglobin • Both require iron to help stabilize its structures
Iron • Deficiency: • Iron-deficiency anemia • Toxicity: • Adult doses can cause poisoning in children • Hereditary hemochromatosis – a genetic disorder in which excessive absorption of iron results in abnormal iron deposits in the liver and other tissues.
Detoxification Molybdenum • Enzymecofactor for sulfite oxidase: sulfite sulfate • Sulfur is critical in our ability (cytochrome P450) to detoxify unwanted contaminant in our liver, and to detoxify heavy metals
Antioxidant Superoxide dimutase (SOD): Cu-Zn SOD Mn-SOD Selenium is part of Glutathione Peroxidase: antioxidant enzyme Glutathione made from Sulfur Molybdenum: Sulfite Sulfate
Thyroids • Thyroid hormone helps regulate body temperature, basal metabolic rate, reproduction, and growth • Iodine: thyroid hormone production (T3, T4) • Selenium: converts thyroid hormone to its most active form (T3)
Cretinism (Iodine Deficiency during Pregnancy) • Severely stunted physical and mental growth due to deficiency of thyroid hormones, usually due to maternal hypothyroidism • Other signs: thickened skin, enlarged tongue, or protruding abdomen.
Fluoride Functions Promotes the deposition of calcium and phosphate in bones and teeth Food sources Fluoridated water Balance Excess can cause fluorosis: discoloration and “specks” on teeth; weakens teeth. The fluoridation debate
Fluorosis Fluoridated water responsible for about 40% of fluorosis Fluoridated toothpaste responsible for about 60% of fluorosis
Absorption vs. Inhibition • Enhances Absorption: • Vitamin C and Iron • Vitamins A, C, E and Selenium • Inhibition/Competition: • Copper, Iron, Zinc, (& Calcium) • Magnesium, Manganese, Calcium (& Iron) • Copper and Molybdenum • Oxalate: Calcium (and non-heme iron) • Phytates: All the minerals
Relationships • Need vitamins B1, B6, and iron to convert Tryptophan to B3 • Copper & Iron • Works with ceruloplasmin, a copper-dependent enzyme required for iron transport. • Copper & Zinc • Wilson’s disease (genetic disorder that increases copper absorption) • Selenium & Iodine • Goiters: Iodine deficiency can be caused by selenium deficiency
Other Trace Minerals and Ultratrace Minerals Arsenic Boron Nickel Silicon Vanadium