o Vitamin D Calcium Phosphorous Magnesium Fluoride Exam III Bone Vitamin C Vitamin E Vitamin A Free Radicals Antioxidants Vitamin K Fat soluble Vitamins D E K A Water Soluble Vitamin C HOW TO READ THIS STUDY GUIDE 1 Each topic is in order of how Farrell discussed them in class What is in GREY is a restatement of something that was already stated in the study guide at an earlier time For example She touched on the sources and functions of calcium when discussing the functions of Vitamin D but waited until later on to discuss calcium in its entirety Therefore I restated the sources and functions of calcium in the main discussion of calcium so you don t have to flip backwards 2 What is in RED are the main topics 3 What is highlighted YELLOW are deficiencies disorders 4 What is highlighted LIGHT BLUE are toxicity disorders 5 What is in BLUE of upmost importance BONE Bone Formation Cortical bone dense compact bone found on the outer shell of bone Trabecular bone softer spongy bone found on the inside of bones It is more metabolically active and has a higher turnover rate and is available for resorption of calcium When we see osteoporosis it is due to the body breaking down this trabecular bone and it occurs first in hips and vertebrae Quick Vocab Review Absorption bringing in nutrients for the first time at the intestines Resorption this occurs mainly in the bone and is the removal of nutrients already in a tissue for use elsewhere Reabsorption occurs in the kidney when nutrients that are set to go to the urine and be excreted in the renal tubules are reabsorbed for use elsewhere Three Main Types of Bone Cells 1 Osteoblasts bone building originate in the bone marrow and are controlled by Parathyroid Hormone PTH and calcitriol depending on the cell these two can down regulate osteoblasts Osteoblasts secrete collagen and bone matrix osteoid Osteoblasts become embedded in the bone matrix and become Osteocytes 2 Osteocytes integrity of the surrounding bone of which they are embedded in these are embedded into the matrix of the bone and are buried alive They maintain the This is the crystal lattice of the bones and teeth which is made up of calcium salts Hydroxyapatite and it lies on top of the bone matrix During mineralization of bone calcium phosphorous and magnesium enter the bone fluid from the blood and attach to the spongy bone proteins such as collagen as well as the ground substance These minerals calcify the bone proteins making our bones hard and strong If the calcium of the hydroxyapatite structure is then reabsorbed by Osteoclasts below in the trabecular bone we see Osteoporosis Bone Proteins made up of collagen osteonectin which binds calcium and collagen and osteopontin which binds hydroxyapatite and bone cells 3 Osteoclasts destroy bone by resorbing the calcium in bone and putting it back into the blood stream Osteoclasts are the carnivore that chews off bone Osteoclasts are large multinucleated cells which contain lysosomes that release acids and proteases that break down the bone by demineralizing the bone proteins Osteoclasts are controlled by PTH calcitriol and calcitonin PTH up regulates osteoclasts calcitriol up regulates osteoclasts and calcitonin down regulates osteoclasts Osteoclasts help maintain blood calcium when we don t consume enough calcium osteoclasts pull the calcium out of our bone and put it into our blood stream Other Bone Cells These cells form collagen proteins which is a long rod shaped protein that provides strength Fibroblasts Collagen also requires Iron Vitamin C and Vitamin D Fibroblasts are also involved in wound healing Chondrocytes substances for bone tendons and ligaments white blood cells These cells can differentiate into osteoblasts Chondrocytes help form the ground These cells make red blood cells specifically in our bone marrow They also make leukocytes Reticulocytes Bond Remodeling There are multiple reasons for the constant remodeling of our bones throughout life growth and maintenance fracture repair and to maintain our serum blood calcium levels Bone Mass Density Bone mass is the greatest and peaks at early adulthood During your adolescent years is usually when you have the greatest amount of activity and is the best time for increasing bone density During postmenopausal years for women you see a great decline in estrogen levels contributing to extreme loss of bone mass since estrogen functions to inhibit bone resorption You can test bone density by DEXA Dual X ray Absorptiometry Exam shows bone mass fat mass and lean mass Gold standard for examining bone Factors Effecting Bone Mass Adding certain things to your diet may be able to decrease bone loss or inhibit bone loss even in elderly women GOOD increases bone mineral density BAD decreases bone mineral density o Protein Intake GOOD Increase protein intake leads to increased calcium excretion in urine Which leads to higher bone density this is opposite of what you would think o Caffeine BAD o Sodium Intake BAD high sodium intake leads to decreased bone density o Mechanical Loading GOOD mechanical loading means weight bearing exercises o Smoking BAD decreases absorption of calcium o Alcohol BAD o Calcium Intake GOOD o Vitamin D GOOD o Phosphorous depends on other factors that we will go over later on o Weight Loss BAD even if they take calcium supplements and do weight bearing exercises o Weight Gain BAD for overweight people leads to fatty bone fat cells inside the bone Increases in Calcium Magnesium and especially Phosphorous are needed during the peak bone forming years of ages 9 18 Men and women see the same declines in bone mass from the ages of 19 30 however males need more magnesium than women Increases of Calcium Vitamin D Magnesium and Phosphorous are needed during the ages of 50 or older International Units IU were created when the importance of Vitamin D supplementation arose in the US as well as in Canada and the UK Calcium Sources 1 Dairy Products 2 Vegetables milk cheese yogurt NOT butter butter is a fat source NOT a dairy source turnip greens mustard greens broccoli cauliflower legumes tofu Spinach is NOT a good source because it contains many oxidants salmon sardines with bones clams anything with a bone in it the bone provides the calcium 3 Seafood 4 Fortified foods orange juice The average child absorbs 75 of the calcium they consume while the average adult absorbs only 30 DRI s Calcium Supplements Calcium citrate malate You will absorb 35 of the calcium from this
View Full Document
Unlocking...