Intakes calcium table

Adequate calcium and vitamin D intake (see Table 88-4) should be assured. For seniors with severe osteoporosis, a 25(OH) vitamin D concentration should be used to guide vitamin D supplementation. Centenarians have a particularly high rate of hypovitaminosis D. Smoking cessation and exercise begun late in life still have positive bone effects. 

Some osteoporosis risk factors (see Table 53-1) are non-modifiable, including family history, age, ethnicity, sex, and concomitant disease states. However, certain risk factors for bone loss may be minimized or prevented by early intervention, including smoking, low calcium intake, poor nutrition, inactivity, heavy alcohol use, and vitamin D deficiency. 

TABLE 53-4. Recommended Daily Calcium and Vitamin D Intake... 

Determine average calcium intake from diet (see Table 53-5) and supplements (see Table 53-6). Compare with age-adjusted recommendations (see Table 53—4). Evaluate the patient s sources of vitamin D. 

All individuals should have a balanced diet with adequate intake of calcium and vitamin D (Table 3-1). Table 3-2 lists dietary sources of calcium and vitamin D. If adequate dietary intake cannot be achieved, calcium supplements are necessary. 

Calcium Adequate intake (Table 3-1) in divided doses Absorption-predominantly active transport with some passive diffusion, fractional absorption 10-60%, fecal elimination for the unabsorbed and renal elimination for the absorbed calcium... 

We have conducted two human metabolic studies (5,6) to compare the effects of increasing phosphorus intake on calcium utilization in healthy young adults maintained at low (ca. 400 mg/day) and high (ca. 1200 mg/day) levels of calcium intake. Increasing dietary phosphorus, as orthophosphate, caused a slight reduction in fecal calcium and a substantial reduction in urinary calcium losses (Table III). 

Table I. Incidence of Demineralization, Fractures, and Rickets at Low and Moderate Calcium Intake...

Dietary intake data for calcium, phytate and phytate/calcium ratio are summarized in Table II. Mean calcium intake for HS-I was about 300 mg greater than the recommended dietary allowance (RDA) of 800 mg established for adults by the National Research Council (8) and for HS-II just slightly less than the RDA. The range of calcium intakes, because of different caloric needs was from 927 to 1490... 

According to food composition tables, the diets used in the study provided an adequate intake of the essential nutrients. Each day, an exact amount of each food served the subjects was saved for analysis of nitrogen, calcium, and sulfur (as sulfate). The results for these elements agreed with those in the literature. These results indicated that during the soy diet, mean intakes were 78.5 g protein, 456 mg calcium, and 2305 mg. of sulfur. Intakes in the meat period were within 37o of those of the soy period. 

A representative example of the effect of phosphorus given as sodium glycerophosphate is shown on Table I. Increasing the phosphorus Intake from 800 mg to 2000 mg per day during a normal calcium Intake of approximately 850 mg per day resulted in a decrease of the urinary calcium from 301 mg to 179 mg per day, the stool calcium increased slightly and the calcium balance became somewhat more positive. 

In extensive studies of the effect of fluoride In patients with osteoporosis carried out In this Research Unit, a therapeutic dally dose of 45 mg fluoride per day was used as sodium fluoride. The main effect of fluoride on calcium metabolism was a decrease of the urinary calcium, while the fecal calcium did not change and the calcium balance also remained unchanged. Also, the Intestinal absorption of calcium remained unchanged during the high fluoride Intake (Table I), The decrease In urinary calcium, Induced by sodium fluoride, may be due to decreased bone resorption, a very desirable effect for patients with osteoporosis. 

Table I shows that the addition of 140 mg of zinc as zinc sulfate per day, during a low calcium Intake of 230 mg/day, decreased the urinary calcium, Increased the fecal calcium and the calcium balance remained unchanged. In nine patients studied during a low calcium Intake, the Intestinal absorption of calcium decreased significantly during the high zinc Intake, the absorption values averaging 61 + 6,6% In the control study and 39 + 4,6% during zinc supplementation, However, the decrease In calcium absorption was abolished...

As shown in Table III, mean fecal calcium losses tended to be higher when the higher fat diet was fed in comparison to results when the lower fat diet was fed. Therefore, apparent calcium absorption was higher when the low fat diet was fed. These differences were significant at only the P< 0.075 level hence, only a trend was illustrated. In this study no attempt was made to equalize fatty acid proportionality patterns or cholesterol intake. These or other dietary or non-dietary factors may have influenced the observed apparent trends. Other studies with human adults have not demonstrated any apparent influence on level of dietary fat on calcium absorption. 

Physiological Responses. The various physiological responses measured in rats at the end of the 5-month feeding period are summarized in Table II. These responses were obtained on diets which were complete in all required nutrients except protein and calcium. Protein was provided at a marginal (10%) or excessive (30%) level while calcium was provided at a submarginal level. These levels represent patterns of intake typical of the American population. 

TABLE 6.2 Criteria upon which Adequate Intake (Al) values were based for calcium by life stage groups"... 

Types of calcium supplements used clinically are listed in Table 31-5. The dose of a calcium supplement should make up the difference between dietary calcium intake and established daily guidelines for each patient. The exact dose for a patient therefore depends on factors such as the amount of dietary... 

The primary roles and the recommended daily intake of major and trace minerals are listed in Table 38-3. Similar to vitamins, these minerals are typically obtained from dietary sources. Specific minerals may likewise be included in various multivitamins and other dietary supplements, with the intent that these minerals will promote good health and prevent disease. Again, there is generally no need for mineral supplements for most people eating a reasonably balanced diet. On the other hand, mineral supplements can be helpful in specific situations where the body s need for a mineral may exceed dietary supply. Some examples of appropriate supplementation include calcium supplements for people with osteoporosis (see Chapter 31), potassium supplements for people on diuretics (see Chapter 21), and iron supplements for people with certain anemias. Hence, mineral supplements may be helpful in certain individuals, but the dose and type of supplement should be adjusted carefully. 

Table 30-2. Adequate Intakes of Calcium and Vitamin D at Different Ages ...

The main sources of dietary calcium are milk and dairy products. In the United States, it is estimated that 73% of calcium is obtained from milk products, 9% from fruit and vegetables, 5% from grains, and about 12% from all other sources combined. The optimal intake of dietary calcium depends on age, gender, and physiological status and is summarized in Table 30-2. 

The alkaline earth metals (group 2A of the periodic table) include Mg and Ca, which play both structural and physiological roles. Aside from its structural importance in bones and teeth, calcium is critical in processes ranging from vascular tone, nerve impulse transmission, muscle contraction, blood clot formation, the secretion of hormones such as insulin, and cell signaling. Calcium levels in cells, blood, and extracellular fluid are very tightly controlled. If calcium intake is insufficient, calcium is liberated from bones in order to support these physiological functions. 

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