Intakes, calcium, long term

Ensure adequate vitamin D and calcium intake during long-term therapy... 

The present communication is concerned with calcium balance studies carried out during the Intake of a variety of dietary factors including minerals and protein as well as drugs. The studies were performed In adult males under strictly controlled conditions in the Metabolic Research Unit. The diet was kept constant throughout the relatively long term studies and complete collections of urine and stool were obtained. The composition of this diet was previously described (5). The diet and the excretions in urine and stool were analyzed for calcium throughout the studies. These data formed the basis of calcium balances which were determined for several weeks. Calcium was analyzed by atomic absorption spectroscopy (6). 

Non-compliance is a serious problem in the prevention of osteoporosis and osteoporotic fractures. This is due to adverse effects, lack of noticeable benefit and ignorance. It is difficult to convince regular intake of oral calcium, biphosphonates, vitamin D and in post-menopausal women hormone replacement. Long-term compliance to hormone replacement is worse in developing countries. The most cost-effective therapy for osteoporosis is primary prevention. 

The long-term intake of hydralazine could lead to vitamin B6 deficiency, while the therapeutic effects of verapamil could be antagonized by calcium supplements. 

Consider vitamin supplementation and monitor iron status for long-term use of cholestyramine Ensure adequate calcium, vitamin D intake by spacing supplements at least 2 h from administration of cholestyramine... 

Vitamin D is responsible for maintaining calcium homeostasis. Low calcium concentrations lead to hyperparathyroidism and bone resorption. Vitamin D insufficiency (11 to 20 ng/mL) and deficiency (<10 ng/mL) [25(OH) vitamin D measurement, 10 ng/mL = 25 mcmol/L] is becoming more commonly recognized in all age groups, ° especially malnourished individuals, northerners, women wearing veiled dresses, African-Americans, seniors, and long-term care residents. Low vitamin D concentrations resnlt from insufficient intake, decreased sun exposure, decreased skin production, decreased liver and renal metabolism, and winter residence in northern climates. 

Given the increased rates of obesity seen post-OLT, dietary counseling on the long-term appropriateness of a low-fat, lean meat diet that is low in sodium and rich in calcium and vitamin D should be provided to these patients. If intake of calcium and vitamin D is inadequate, supplements should be given to assure a total intake of 1,500 mg of elemental calcium and 400 to 800 international units of vitamin D. 

With dietary restriction of dairy products, adequate calcium intake is difficult to be achieved without supplements. Low bone density has been reported (Kaufman et al., 1995a Panis et al., 2004), although the long-term complications of bone health are not well characterized. 

Various components of dietary fibre also have considerably different ion-exchange capacity. A long-term excessive intake of dietary fibre may bring about symptoms of calcium, iron and zinc deficiency. This reduced resorption of minerals is especially pronounced for high doses of fibre and likewise of phytic acid. 

When calcium absorption is chronically low, because of low intakes, poor bioavailability, or conditions that impair intestinal absorption, there is a decrease in the serum ionized calcium concentration. This in turn stimulates the release of PTH, which returns serum calcium to normal by increasing renal calcium reabsorption, stimulating the renal production of 1,25(0H)2D3, and inducing bone reabsorption. The result of long-term calcium deficiency is accelerated bone loss in older individuals or the inability to fully achieve peak bone mass in younger individuals. 

Long-term consumption of approximately 1500-2000 mg calcium per day is safe for most individuals, although there will be some reduction in the efficiency of iron absorption. However, higher intakes from supplements (62.5 mmol or 2.5 g per day) can result in milk-alkali syndrome (MAS), with symptoms of hypercalcemia, renal insufficiency, metabolic alkalosis, and severe alterations in metabolism. Based on risk of developing MAS, the upper Hmit for calcium intake is 2500 mg per day for adults and children. 

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