Calcium is the major component of bone that confers strength. As such, low calcium levels can lead to osteoporosis, a disruption of the architectural framework of bone that weakens it. Osteoporosis can be prevented by increasing your dietary intake of vitamin D and calcium. Increasing sunlight exposure helps to increase calcium by increasing synthesis of vitamin D in your skin.
Nutrition and Calcium Regulation
Calcium is mainly absorbed from food sources that are rich in calcium such as fortified oatmeal, sardines, cheddar cheese, milk, yogurt and soybeans. Vitamin D facilitates the absorption of calcium from the intestines. Blood calcium is regulated by the parathyroid and thyroid glands. These glands produce parathyroid hormone and calcitonin, respectively. Low blood calcium stimulates the parathyroid gland to produce parathyroid hormone, which acts on bone, causing it to break down and thereby release calcium into the bloodstream. The thyroid gland produces calcitonin in response to elevated calcium in blood; calcitonin causes the removal of calcium from the blood.
Osteoporosis can occur due to low blood calcium or due to increased breakdown of bone. Diseases that lead to osteoporosis prevent the use of calcium in maintaining bone.
Risk Factors
The risk for osteoporosis increases with advanced age in both men and women, with women being at highest risk for osteoporosis. In women, estrogen levels drop during menopause, leading to a rapid loss in bone strength; in men, a drop in the male sex hormone, testosterone, has less effect on bone.
Excess alcohol and smoking are major risk factors for osteoporosis that can be avoided. Other risk factors include vitamin D deficiency and malnutrition. Being physically inactive can also cause a major loss in bone strength.
Prevention
Osteoporosis can be prevented by making necessary changes to lifestyle such as quitting smoking and drinking. Bone weakens with advancement in age, but regular exercise such as walking and jogging slows down the loss in bone strength. Exercise should be at least 30 minutes a day, at least four days per week. Proper dietary intake of vitamin D and calcium can prevent osteoporosis. Diet should include fish, eggs, vitamin D-fortified milk and cod liver oil, which are all abundant sources of vitamin D. Vitamin D is synthesized under the skin under direct sunlight. Adequate sunlight exposure helps prevent osteoporosis.
Associated Symptoms
Osteoporosis has no specific symptom but is associated with bone fractures that occur without significant stress on bone. Fractures can occur anywhere throughout the body. When it occurs in the back, it can affect posture and reduce mobility. Fracture of a long bone such as the femur is a serious complication that requires surgery.
The elderly have increased risk of falls and osteoporosis increases the likelihood of fractures associated with falls.
Screening and Diagnosis
Osteoporosis can be confirmed with the use of radiographic imaging such as X-rays, CT scans or MRIs. Imaging studies are only effective for detecting late stages of osteoporosis; it detects mainly fractures. Measuring the bone mineral density by using dual energy X-ray absorptiometry is effective in diagnosing osteoporosis in both the early and late stages.
The U.S. Preventive Services Task Force recommends the screening of all women above the age of 65 years and post-menopausal women under 65 years old who are below ideal weight. Screening can lead to earlier treatment and reduction in fracture risk.
