How much vitamin D do I need?
In November 2010, the Institute of Medicine's expert committee set a new "dietary reference intake" for vitamin D.
Assuming that a person gets virtually no vitamin D from sunshine -- and that this person gets adequate amounts of calcium -- the IOM committee recommends getting the following amounts of vitamin D from diet or supplements (Note that the IOM's upper limit is not a recommended intake, but what the IOM considers the highest safe level):
Calcium: A mineral found mainly in the hard part of bones. Calcium is essential for healthy bones and important for muscle contraction, heart action, nervous system maintenance, and normal blood clotting.
DXA: Dual energy X-ray absorptiometry. It is used to measure bone mineral density.
Fracture: A break in bone. Although usually the result of trauma, a fracture can be caused without significant trauma in bones that are weakened.
Hip Fracture: Broken bone in the hip, a key health problem among the elderly, usually due to a fall or other kind of trauma involving direct impact to the hip joint, especially if osteoporosis is present.
Hyperparathyroidism: Too much parathyroid hormone resulting in abnormally high levels of calcium in the blood. This can cause bone resorption and osteoporosis, calcium deposits in the kidneys, and other health problems.
Osteopenia: Mild thinning of the bone mass, but not as severe as osteoporosis. Osteopenia is generally considered the first step on the road to osteoporosis.
Osteoporosis: Thinning of the bones with reduction in bone mass due to depletion of calcium and bone protein. Osteoporosis can lead to posture changes, deformity, and fractures, with resulting decreased mobility.
Postmenopausal: After menopause. The time after which a woman has experienced twelve (12) consecutive months without a period.
Vitamin D: A steroid vitamin that promotes the absorption and metabolism of calcium and phosphorus. Sunlight promotes vitamin D synthesis in the skin. Vitamin D is also present in fatty fish such as salmon, mackerel and tuna, and in fortified foods.