Osteoporosis
Is a disease characterized by low bone mass, deterioration of bone tissue, fragile bone leading to bone fracture, shortening of bone; decreased height, and shortening and hunching of the spine.
Risk factors for Osteoporosis
Age, all women, premature Menopause, family history, smoking, heavy/regular use of alcohol, underweight, poor dietary intake, and sedentary lifestyle or bed-confinemet.
Age is a factor for osteoporosis because
Bone mass decreases with age, age-related hormonal changes influence bone density, and older adults are less able to absorb Vitamin D.
Gender is a risk factor for osteoporosis:
80% of Americans with this are women, women have a lower bone density than men, low estrogen production increases bone loss; post-menopausal women and adolescent girls engaged in extreme dieting.
Problems with decreasing bone density:
Osteoporosis leads to osteoarthritis- crippling pain in joints and bone fractures, often the hip, hip fracture in older person may lead to other problems: pneumonia, inability to move independently, and death.
Smoking and poor nutrition increase osteoporosis risk:
Cigarette smoke effects hormones that influence bone formation and resorption, alcoholism is associated with fractures, and caffeine may increase urinary calcium loss.
Physical activity influences the risk for osteoporosis:
Regular exercise causes stress to bones, leading to increased bone mass, weigh-bearing activities (walking, jogging) are especially helpful in increasing bone mass, and improved muscle strength and physical stability reduced the risk of falling and bone f
Female athlete triad is a condition characterized by:
Eating disorder-inadequate food intake and regular strenuous exercise combined, result in a state of severe energy drain that causes a multitude of hormone changes including a reduction in estrogen production, amenorrhea- from a reduction in estrogen prod
Treatment
There is no cure for osteoporosis, the progression of it may be slowed by: adequate calcium and vitamin D intake, regular exercise, anti-resorptive medications such as Fosamax and Estrogen, and Hormone Replacement Therapy.
Bone structure
Provides strength to support the body, allows for flexibility, contains about 65% minerals providing the hardness of bones, contains 35% organic structures for strength, durability, flexibility, and collagen: fibrous protein in bone tissue.
Two type of bone tissue
Cortical bone and trabecular bone.
Cortical bone
AKA compact bone; is a very dense tissue making up 80% of the skeleton.
Trabecular bone
AKA spongy bone; "scaffolding," on the inside of bones; supports the cortical bone and makes up 20% of the skeleton.
Bones develop through three processes:
Bone growth, bone remodeling, and bone modeling.
Bone growth
Increases in bone six; completed by age 14 in girls and 17 in boys.
Bone modeling
Shaping of bone; completed by early adulthood.
Bone remodeling
Reshaping of bone.
Bone remodeling involves:
Resorption and formation of new bone cells called osteoblasts.
Resorption
Sufrace of bones is broken down and osteoclasts are cells that erode the surface of bond.
Osteoblasts
Produce the collagen-containing component of bone.
Bone density
Peak bone density is reached before the age of 30, remodeling maintains this during early adulthood, and this begins to decrease after age 40 because resorption exceeds new bone formation.
Dual Energy X-Ray absorptiometry (DEXA)
Measures bone density, uses very low level X-ray energy, provides a full body scan, is a non-invasive procedure, and is recommended for post-menopausal women.
Calcium
Is the most abundant major mineral in the body and its absorption requires Vitmain D and is enhanced in an acid environment.
Functions of calcium
Form and maintain bones and teeth, assists with acid-base balance, transmission of nerve impulses, and assist in muscle contraction, maintain blood pressure, initiate blood clotting, and regulating various hormones and enzymes. Recent research suggests th
Calcium RDI
AI varies with age and gender from 1,000mg to 1,300 mg per day.
Bioavailability
The body's ability to absorb and utilize calcium depends on: the individual's age and need for calcium, the amount of dietary calcium and vitamin D, and binding factors (phytates, oxalates) in foods that bind with calcium preventing its absorption.
Significant sources of calcium
Milk and milk products, low-fat cheese, nonfat yogurt, fortified foods (orange juice), green leafy veggies (broccoli, kale, collard, greens, and cabbage are low in oxalates), and small fish with bones.
What if you consume too much calcium?
Excess of this is excrete from the body, and these types of supplements can lead to mineral imbalances. Hypercalcemia (high blood calcium) can be caused by cancer or PTH overproduction; may lead to calcium deposits in soft tissues.
What if you don't consume enough calcium?
Osteoporosis; hypocalcemia (low blood calcium) can be caused by kidney disease, vitamin D deficiency, or low PTH production.
Vitamin D
Fat-soluble vitamin, excess is stored in liver and fat tissue, can be synthesized by the body by exposure to UV light from the sun, and is a hormone since it is synthesized in one location, and acts in another location.
Functions of vitamin D
Required for calcium and phosphorous absorption, regulates blood calcium levels, stimulates osteoclasts, and necessary for bone classification.
Recommended Intake of Vitamin D
There is no RDA for this, AI values range from 5 to 15mg/day depending on age and gender, AI values assume that a person's sun exposure is inadequate, and far northern and southern latitudes receive inadequate sun in the winter.
Sources of Vitamin D
Most foods naturally contain very little of this, most is obtained from fortified foods, such as milk, and vegetarians not consuming diary foods receive this from the sun, fortified soy products or supplements.
What if you consume too much Vitamin D?
Can occur from vitamin supplements and results in hypercalcemia- high blood calcium.
What if you don't consume enough Vitamin D?
Can occur with diseases that reduce intestinal absorption of fat. Rickets occurs in children and osteomalacia in adults.
Rickets in children
Inadequate calcification, resulting in misshapen bones (bowing of legs), enlargement of ends of long bones (knees, wrists), and deformities of ribs (bowed, with beads or knobs). Deficiency symptoms: Delayed closing of fontanel, resulting in rapid enlargem
Osteomalacia in adults
Loss of calcium, resulting in soft, flexible, brittle, and deformed bones. It is a progressive weakness, pain in pelvis, lower back, and legs.
Vitamin K
Fat-soluble vitamin stored in the liver, phylloquinone- plant form, menaquinone form produced by bacteria in the large intestines.
Functions of Vitamin K
Blood coagulation and bone metabolism which assists in the production of osteocalcin, a protein that is associated with bone turnover.
Recommended intake of Vitamin K
There is no RDA for this vitamin and AI values are 120mg/day for men and 90mg/day for women.
What if you consume too much Vitamin K?
No side effects from large quantities, however will interfere with anticoagulant medicine. Mainly from supplements- Coumadin and Warfarin.
What if you don't consume enough Vitamin K?
Reduced blood clotting, excessive bleeding, and can occur with diseases that disturb absorption of fat in the small intestine.
Phosphorous
Is the primary intracellular negatively charged electrolyte.
Functions of Phosphorous
Critical to mineral composition of bone, calcium and phosphate crystalize to form hydroxyapatite crystals, which provide the hardness of bone, about 85% is stored in bones, with the rest stored in soft tissues such as muscles and organs.
Food Sources of Phosphorous
Various foods, dairy, bakery products, sodas, and meats, processed foods, some from food additives, current intake exceeds RDA, and deficiency highly unlikely
What if you consume to much phosphorous?
Excessive vitamin D supplements can cause high levels of this, muscle spasms, and convulsions. Higher risk for people with kidney disease.
What if you don't consume enough phosphorous?
Calcification of non-skeletal tissues, particularly the kidneys, results in inefficient function, phosphate ions bind calcium, and chronic imbalance may lead to bone loss. Combination of drinking several soft drinks without drinking milk or eating milk pr
Magnesium
50-60% is found in bones. Its functions include that it is a mineral found in bone structure, cofactor for over 300 enzyme systems, required for the production of ATP, DNA, and proteins, and supports vitamin D metabolism, muscle contractions, and blood cl
Food sources of Magnesium
Green leafy veggies, whole grains, seeds, nuts, seafood, beans, dark chocolate, and some dairy products.
What if you consume too much magnesium?
No toxicity from this mineral is found in food, however this type of mineral supplements can cause diarrhea, nausea, cramps, dehydration, and often in the form of laxatives.
What if you don't consume enough magnesium?
Hypmagnesium can result in low blood calcium and osteoporosis.
Fluoride
Is a trace mineral, 99% is stored in teeth and in bones. Functions include the development and maintenance of teeth an bones, and combines with calcium and phosphorous to protect teeth from bacteria.
RI for Fluoride
AI varies by gender and increased with age, ranging from 1-4mg/day.
Sources of Fluoride
Fluoridated dental products and fluoridated water.
What if you consume too much Fluoride?
Fluorosis (excess fluoride) creates porous tooth enamel; teeth become stained and pitted.
What if you don't consume enough Fluoride?
Dental caries (cavities).