° Lesson 3 (Minerals III) : ° Calcium (Ca 2+ ) 99% of it used for formation of bones & teeth 1% used for nerve transmission & blood clotting o Determined by Sydney Ringer (1883) that the body needs Ca 2+ for nerve impulses to function Intake varies enormously Recommended amounts also vary ° Nutritional status of elite swimmers o Males RDA of calcium is 2.7 times higher than regular RDA o Females 1.18 times higher Net Calcium intake: o Intake = 250mg, 85mg lost in urine, 265 lost in stool. Net intake of -100mg Much of it is lost & excreted ° Osteoporosis Linked to low dietary calcium ~9 mill. associated fractures worldwide Affects women more than men (affects men who are >60 usu.) Risk factors: o Short stature
o Underweight o Early Menopause o Physical Inactivity o Alcoholism o Smoking o Excess Caffeine o Excess Protein o Excess Fiber Resorption for post menopausal women is 1 – 5% per year o Resorption is the loss of bone mass o At 5% per year, ½ the bone mass is gone in ~14 years
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- Spring '10
- bone mass, Uterine cancer