Major Minerals and Trace Minerals - Part 1 PDF

Major Minerals (body storage of more than 5 grams) Chapter 10, 11 1 Minerals in a 60-kilogram (132-pound) Human Body MAJOR MINERALS The major minerals are those present in amounts larger than 5 g (a...

Major Minerals (body storage of more than 5 grams) Chapter 10, 11 1 Minerals in a 60-kilogram (132-pound) Human Body MAJOR MINERALS The major minerals are those present in amounts larger than 5 g (a teaspoon). A pound is about 454 g; thus only calcium and phosphorus appear in amounts larger than a pound. TRACE MINERALS There are more than a dozen trace minerals, although only six are shown here. Amount (g) 2 3  Minerals in the Body Minerals are elements needed by the body in small amounts for health and maintenance. Major minerals are needed in the diet in amounts greater than 100 mg per day or are present in the body in amounts greater than 0.01% of body weight. Trace minerals are required in the diet in amounts less than 100 mg per day or are present in the body in amounts less than 0.01% of body weight. 4  Sodium Major cation of the extracellular fluid Functions 1) maintains water balance 2) maintains acid-base balance 3) muscle contraction 4) nerve conduction About 90 - 95% is loss through the urine the rest is lost in feces and sweat Normally, Na excretion = Na ingested 5  Sodium Sodium balance is regulated by aldosterone Aldosterone - a hormone secreted by the adrenal glands, stimulates reabsorption of Na by the kidneys 6  Sodium Estrogen, can cause sodium and water retention. Changes in water and Na balance during: the menstrual cycle, pregnancy, and, oral contraceptive use, are partially attributable to changes in progesterone and estrogen levels. 7  Too much Sodium in the Diet Na and hypertension, now linked to NaCl Sodium increases the body’s need for water Edema (is a result of the accumulation of body water due to a high [ ] of solutes such as sodium) high dietary Na has been associated with high excretion of calcium (influences on bone loss is not clear) 8  Symptoms of LOSS of excess Na in the body muscle cramps decrease BP loss of appetite high hematocrit (volume of RBC) dehydration (sodium gets excreted with water) hyponatremia - too little Na in the blood 9 10  Sodium - Dietary Sources/RDA 1 teaspoon of salt = 2000 mg of Na (2 grams) UL – 2300mg/day AI – 1500mg/day The average Canadian consumes 4,000 to 5,000 mg/day 11  Dietary Sources of Na Soft water ********* processed foods ********** about 75% of the Na in a person’s diet comes from processed foods and canned foods 15% comes from adding during cooking, 10% naturally occurring in foods MSG – monosodium glutamate - “Chinese Restaurant Syndrome” - some people have a reaction to MSG - sweating headache, nausea, rapid heart beat (symptoms of a heart attack) 12  Sodium - Dietary Sources 1 cup broccoli: 64 mg 1 oz salted peanuts: 90 mg 1 cup cornflakes: 203 mg 1 bagel: 379 mg 1 cup tomato/V8 juice: 654 mg 1 cup canned soup: 600 - 2000 mg 1 TBSP soy sauce: 914 mg Big Mac: 1090 mg KFC chicken breast: 1116 mg 2 slices pepperoni pizza: 1417 mg 13 14 Dietary Approaches to Stop Hypertension: Designed to reduce hypertension 15  Sodium Intake of Canadians Upper Limit (UL) = 2300mg 90.2% of males (>19 years) above the UL 65.7% of women (>19 years) above the UL The average intake of sodium in the Canadian Diet is 3400mg A concern is that excessive sodium intake is associated with increased risk for hypertension. The Sodium Reduction Strategy for Canada recommends that Canadians reduce their sodium intake to < 2300mg/day 16 17 18 List 5 ways that an individual can reduce sodium (salt) intake in the diet 19  Potassium (K) Major intracellular cation FUNCTIONS 1) maintains normal fluid and electrolyte balance 2) conduction of nerve impulse transmission 3) control of muscle contraction, (esp heart) - If the heart cells give up only 6% of the potassium they contain, the heart would stop beating - eg. anorexia - The heart will also stop beating with extremely high amounts of potassium 20  Potassium Deficiency Low K – hypokalemia Causes of low potassium in the body – Diuretics (dehydration) – Potassium supplements are usually prescribed when diuretics are used Symptoms Irregular heart beat Muscular weakness 21  Regulation of Na and K Na-K pump cell membranes are highly permeable to K but as it leaks out, a pump puts the K back into the cells, therefore exchanging Na and K uses ATP to do this 22  AI and Dietary Sources of K AI (adults) – 4700 mg/day High dietary sources – vegetables and fruits - orange juice (473 mg per cup) - potatoes (844 mg for 1 each) - bananas (451 mg for 1 each) - cantaloupe (825 mg per ½ each) - broccoli (526 mg per 1 spear) Also - table salt (contains potassium iodide) DASH diet emphasizes potassium-rich foods such as fruits and vegetables and the reduction of sodium 23  Potassium Intake of Canadians The average Canadian diet contains 2500 to 3500 mg of potassium/day, which is well below the recommendation of 4700 mg/day. Following Canada’s Food Guide and the Dash Diet recommendations would result in a potassium intake of 8000 to 10,000 mg/day. 24 Best Source of Potassium in the diet (per kcal): Vegetables and Fruits 25  Chloride (Cl) Major anion of extracellular fluid Functions 1) maintain fluid balance 2) maintain acid-base balance - one of the major consequences of vomiting is the loss of acid from the stomach - this upsets the acid-base balance in the body 3) necessary for proper digestion - part of HCl in stomach - facilitates protein digestion and iron absorption 26  AI and Dietary Sources of Cl Found in any foods with Na (NaCl) Processed foods are the highest AI (adults)2300 mg/day UL (adults) 3600 mg/day (because of Na) 27 Summary of Water and the Electrolytes 28  Calcium (Ca) Most abundant mineral in the body - 1150g 99% - stored in the bones and teeth 1% - blood and body fluids (but vital to life) Functions in the Body – Bones 1) protect and strengthen bones 2) serves as a storage site 29  Functions of Ca – blood and body fluid 1) muscle contraction (including heart) 2) transmission of nerve impulses 3) regulates BP 4) blood clotting 5) cofactor for enzymes (substance that binds to an enzyme to activate it) 6) secretion of hormones 7) others 30  Absorption of Ca 25% absorbed 50% absorbed during pregnancy 50 – 60% absorbed during growth (children) 31  Factors affecting Ca absorption 1) high acidity of stomach (↑) Lack of stomach acid decreases absorption therefore antacids such as TUMS decrease Ca absorption (maybe this is why TUMS adds Ca to the product) 2) Vitamin D (↑) 3) lactose in dairy (↑) 4) phytic acid and fibre (husks of grains) (↓) 5) oxalic acid (green leafy and others) (↓) 6) growth/growth hormones (↑) 7) pregnancy (↑) 8) aging (↓) 32  Regulation of Ca If blood [Ca] gets too low: - the intestines increase Ca absorption - the bones increase Ca release - the kidney decreases Ca excretion If blood [Ca] gets too high: - Ca will get deposited into the bones 33  Blood Ca concentration is controlled by: 1) PTH (parathyroid hormone or parathormone) 2) Vitamin D 3) Calcitonin Blood [ ] of Ca must be closely regulated by the body If blood serum levels are LOW, the body draws the storage OUT of the bones 34  Calcium Balance Falling blood calcium Rising blood calcium Thyroid Parathyroid signals the parathyroid signals the thyroid (embedded glands to secrete gland to secrete in the thyroid) parathormone. calcitonin. Calcitonin Parathormone (PTH) inhibits the activation Calcitonin stimulates the activation of vitamin D. Parathormone of vitamin D. Vitamin D Calcitonin Activation Vitamin D and PTH prevents calcium stimulate calcium Vitamin D reabsorption reabsorption in the in the kidneys. kidneys. Vitamin D Calcitonin limits Kidneys enhances calcium calcium absorption in the absorption in the intestines. intestines. Calcitonin inhibits Vitamin D and PTH osteoclast cells from stimulate osteoclast cells to Intestines break down bone, breaking down bone, preventing the releasing calcium into the release of calcium. blood. All these actions lower blood All these actions raise blood calcium levels, which inhibits calcium levels, which inhibits 35 calcitonin secretion. Bones parathormone (PTH) secretion.  Maintaining Blood Calcium from the Diet and from the Bones With an adequate intake of With a dietary deficiency, calcium-rich food, blood blood calcium still remains calcium remains normal... normal......and bones deposit...because bones give up calcium. The result is calcium to the blood. The strong, dense bones. result is weak, osteoporotic bones. 36  Osteoporosis Reduced density of the bones means porous bones 37 38 Loss of Height in a Woman Caused by Osteoporosis 6 inches lost 50 years old 80 years old 39 40  Bone Losses over Time Compared Woman A entered adulthood with enough calcium in her bones to last a lifetime. Bone mass Woman B had less bone mass starting out and so suffered ill effects from bone loss later on. Danger zone Osteoporosis Age 30 Menopause Age 60 Time 41  Phases of Bone Development throughout Life Peak bone mass Bone density years Active growth Bone loss 3 phases of bone development Bone mass is: 1. Active growth phase - 20% higher in males - occurs from birth to 20 years of age 2. Peak Bone Mass development than females - occurs between the ages of 12 and 30 - 10% higher in African- 3. Bone Loss American people - ages 30 to 40 42  Osteoporosis females experience a slow bone loss before menopause: about 10% after peak bone mass Women experience rapid bone loss for 6 - 8 years following menopause (decreased estrogen) men: 3% every decade after peak bone mass Most cases of osteoporosis are women 43  Osteoporosis Bone loss rates will vary (for both M and F) between persons from 25 - 75% depending on: - amount of peak bone mass - mineral storage (nutrition) - hormonal changes (estrogen in women, testosterone in men) - physical activity Age (strongest predictor) Gender (2nd strongest predictor) Others: smoking, alcohol, caffeine) 44  Types of Osteoporosis Type I Type II Age of Onset 50 to 70 years old 70 years and older Fracture Sites Wrist and Spine Hip Gender Incidence 6 women to 1 man 2 women to 1 man Primary Causes Rapid loss of Reduced calcium estrogen in women absorption following Increased bone menopause mineral loss Loss of Increased risk of testosterone in men falling with advancing age 45 46  Prevention of Osteoporosis 1) Ca during childhood most important 2) Ca supplement during and after menopause 3) exercise!!!!!!!!!!!!!!!!!!!! Research has shown that weight bearing exercise improves bone density (DXA) in both children and adults 47  Calcium in the Diet Intake of soft drinks is affecting the calcium intake of teenagers. Canadian adolescent males (14–18 years) consume an average of 376 ml/day of regular soft drinks and adolescent girls consume 179 ml/day. Milk intake declines with age. 48  Calcium in the Diet Soft drinks are replacing milk, have no calcium and are higher in sugar. Low calcium intake early in life increases the risk of osteoporosis and increases the number of overweight and obese individuals. 49  Calcium in the Diet One multivitamin and/or mineral supplement will not provide enough calcium to meet your needs. Read labels to find a supplement that contains calcium with Vitamin D (which aids in absorption of calcium). The form of calcium is also important. Calcium carbonate should be taken with a meal, whereas calcium citrate can be taken at any time. Antacids that contain aluminum and magnesium may interfere with calcium absorption. 50 DRI: 19 – 50 yrs old, 1000 mg/day > 50 yrs old, 1200 mg/day Calcium in Foods UL: 2500 mg/day 250 ml Milk: 300 mg 250 ml Cheddar cheese: 204 mg Best Dietary Sources: 250 ml Yogurt: 452 mg Milk, Yogurt, Cheese 62 ml Almonds: 97mg 2 TBSP Blackstrap molasses: 342mg OJ: must be fortified Soy milk: must be fortified 90 g Canned sardines: 211 mg TUMS: no, decreases stomach acid which is required for Ca absorption 51 Best Dietary Sources of Calcium: Milk, Yogurt, Cheese Canned Fish with Bones (sardines, salmon) 52 Phosphorous (phosphoric acid, phosphate) 2nd largest in body 85% is stored in bones and teeth 53  Functions of Phosphorous 1) Main Function: structural components of bones and teeth 2) regulates pH of the stomach (acts as a buffer) 3) structural component of nucleic acids (DNA, RNA) 4) structural components of coenzymes (NADP, FADP, TPP, pyridoxal phosphate) 5) structural component of fats 6) involved in energy transfer (ATP, ADP) 54 Phosphorus:Best Dietary Sources: Protein Foods 55  Sulphur (Sulphate) Sulphate is the oxidized form of sulphur (as it exists in food and water) The body does not use sulphur as a nutrient by itself, but occurs in nutrients that the body does use part of: – the amino acids: methionine and cysteine – B vitamins: thiamin and biotin 56  Function of Sulphur Determines the shape of proteins found in hair, nails, skin In hair processing (perm or straightening), sulphur rearranges the protein molecules in the hair strands DRI - none 57  Magnesium most is stored in bone along with Ca and P (60%) Many calcium supplements often include magnesium 58  Magnesium: Function 1) maintaining bone health (over half of the body’s magnesium is stored in bones along with Ca and P) 2) promotes resistance to dental carries (tooth decay) by holding calcium in tooth enamel 3) involved in the synthesis and breakdown of fats, CHO, and protein 4) helps relax muscles after contraction 5) needed for transmission of nerve impulses 6) regulates hormones/enzymes (ATPase, pyruvate, others) 7) heart function (deficiency of Mg, the arteries constrict, contributing to CVD) 59  AI and dietary sources of Magnesium AI (adults): Males – 420 mg/day Females – 310 mg/day Toxicity is rare UL: 350mg (non-food sources) Best dietary Sources: Nuts/seeds/beans/legumes/bran Leafy greens (because it’s a component of chlorophyll) 60 Magnesium in the Diet: Best sources: nuts, seeds, legumes, leafy greens 61 62  Review Questions 1. Adequate calcium absorption depends on adequate levels of Vitamin ______. 2. Which of the following foods would have the highest amount of sodium? Canned tomato soup, frozen broccoli, skim milk, white bread 3. Which of the following foods would have the greatest amount of potassium: Vegetables, fish, bagel, chicken 4. The majority of magnesium is stored in the: Skin, Liver, Bones, Kidneys 5. The major cation of the extracellular fluid is _____________. 6. The DASH diet was developed to reduce ________________. 63