14 terms

Bone Health

about 65% of bone tissue is made up of an assortment of minerals that provide hardness, but the remaining 35% is a mixture of organic substances that provide strength, durability, and flexibility. the most important of these is a protein called collagen. this design enables bones to bear weight while responding to demands for movement.
Describe the composition of bone.
(compact bone) very dense. it comprises approximately 80% of the skeleton. this is the outer surface of the bone. it contains many microscopic openings that serve as passageways for blood vessels and nerves.
Cortical bone
(spongy bone) this makes up only 20% of the skeleton. it is found within the ends of the long bones. it is aligned in a precise network of columns that protect the bone from extreme stress. this bond is more susceptible of osteoporosis because it is more sensitive to changes in hormones and nutritional factors, this bone is being broken down and replenished at any given time as compared with cortical bone.
Trabecular bone
the size of bone increases, growth continues in spurts throughout childhood and adolescence. girls reach adult height by 14 and boy by 17.
Bone growth
the shape of bones is determined. this process causes bone to continue to increase in thickness if they are stressed by repetitive exercise.
Bone modeling
bone mass is recycled. also used to repair bone that has been broken or damaged and to strengthen bone regions that are exposed to higher physical stress. two steps: the breakdown of existing bone, and the formation of new bone. osteoclasts erode the bone surface by secreting enzymes and scrubbing brush to assist in the erosion process. osteoblasts are bone builders, the hydroxyapatite crystallizes and packs together to create new bone where it is needed.
Bone remodeling
DXA: the most accurate assessment tool. measure the density of the bone mass over the entire body. it is simple, painless, safe and noninvasive. it is assessed through the use of very low x-ray levels.
How is bone density measured?
some foods have ingredients that can inhibit the bodys ability to absorb calcium. foods the include phytate and xalate are in this category. these foods include beet greens, spinach and rhubarb. pinto beans and other legumes have high phytate levels. the phytate level can be reduced by soaking the beans first for a few hours in water.
What factors decrease calcium absorption.
vitamin d is necessary for your body to properly absorb calcium so make sure you are getting enough. many calcium supplements include vitamin d. if you are taking calcium supplements, its also a good idea to take them with meals because the produces stomach acid, which helps your body absorb calcium. or you can take with a glass of orange juice to boost absorption.
What factors increase calcium absorption?
when the uv rays of the sun hit the skin, they react with 7 dev. this compound is converted to cholecalciferol, which is then converted to calcidiol in the liver. calcidiol travels to the kidneys where it is converted into calcitriol, which considered the primary active form of vitamin d in our bodies.
Explain the process by which the body makes vitamin d from exposure to the sun.
season, latitude, time of day, age, weather, skin exposure, sunscreen use, skin color, glass/plastic.
What factors enhance and inhibit vitamin d synthesis and why?
Osteoporosis is a disease characterized by low bone mass and deterioration of bone tissue, leading to enhanced bone fragility and increase in fracture risk. It is the leading cause of fractures of the hip and spine in older adults. It impacts the physical activity of individuals with it, deteriorates their bones, causes weak bones, and impacts bone health. Individuals with osteoporosis are encouraged to consume adequate exercise programs including weight bearing exercises such as jogging, stair climbing and resistance training. Women are at higher risk because of menopause, they have a lower absolute bone density than men, women have a more dramatic effect on bone density during hormonal changes, and women live longer than men.
What is the world healthy organization definition of osteoporosis? discuss how it affects a persons healthy, describe why women are at greater risk than men for their disease, and treatment options.
smoking, low body weight, low calcium intake, low sun exposure, alcohol abuse, estrogen deficiency, testosterone deficiency, repeated falls, sedentary lifestyle.
Modifiable factors that influence the risk of osteoporosis.
older age, caucasian/asian race, history of fractures as an adult, family history, female.
Non-modifiable factors that influence the risk of osteoporosis.