Sodium daily requirement

The elements essential for life can be divided into macroelements (daily requirement > 100 mg) and microelements (daily requirement < 100 mg). The macroelements include the electrolytes sodium (Na), potassium (K), calcium (Ca), and magnesium (Mg), and the nonmetals chlorine (Cl), phosphorus (P), sulfur (S), and iodine (I). 

The most common use of salt is as part of daily diets. Although it is added directly to food, 75% of the salt consumed in the United States is a result of eating processed foods The National Academy of Sciences has determined that a minimum daily requirement of 500 mg of sodium is safe, which equates to 1,300 mg of salt. The Academy and the federal government recommend that sodium consumption be no more than 2,400 mg per day, which equals 6,100 mg of salt. Most Americans consume levels higher than this, and many health organizations recommend decreasing salt intake. Excess salt can lead to health problems such as elevated blood pressure, although recent research seems to indicate that normal or moderately... 

Minerals include sodium, potassium, calcium, phosphorus, magnesium, manganese, sulphur, cobalt and chlorine trace minerals include iron, zinc, copper, selenium, iodine, fluorine and chromium. Their roles may be generalised within the areas of providing structure in the formation of bones and teeth, maintenance of normal heart rhythm, muscle contractility, neural conductivity, acid-base balance and the regulation of cellular metabolism through their activ-ity/structural associations with enzymes and hormones. The daily requirements of minerals can be obtained from a well-balanced diet. 

Milder forms of volume depletion may be managed in outpatient settings. For example, supplemental fluids can be added to the usual estimated daily requirements of 30 to 35 mL/kg in patients older than 12 years of age with dehydration. Commercially available carbohy-drate/electrolyte drinks generally are more palatable than water and may promote earlier recovery. When the dehydration involves substantial losses of salt as well aswater, additional sodium may need to be added to these drinks because they usually contain 50 mEq/L or less of sodium. This is less than the amounts of sodium (e.g., 90 to 120 mEq/L) generally recommended for rehydration." The additional sodium will increase osmolarity, but this does not appear to delay gastric emptying." Also, guidelines for oral rehydration of children with acute diarrhea are available, which, if used appropriately, may prevent future hospitalization." Intravenous rehydration of... 

The normative sodium requirement of adults is not exactly known, but the lowest individual daily intakes measured were 1300 mg in women and 1600 mg in men. The normative daily sodium requirement of women is < 1300 mg (< 3.3 g NaCl), while that of men is <1600 mg (<4.0g NaCl). The basal daily requirement of sodium in adult humans may be much lower, amounting to 460 mg (1.3 g NaCl). Healthy women and men have been recom-... 

The patient receives sodium when food is absorbed in the GI tract. Typically, a patient takes in more sodium than the patient s daily requirement. The kidneys regulate the sodium balance by retaining urine when the sodium concentration is low and excreting urine when the sodium concentration is high. Most excess sodium is excreted in urine although sodium also leaves the patient as perspiration and in feces. 

Potassium is widely recognized as an essential element. In fact, our daily requirement for potassium is more than twice that for sodium. Because most foods contain potassium, serious deficiency of this element in humans is rare. However, potassium deficiency can be caused by kidney malfunction or by the use of certain diuretics. Potassium deficiency leads to muscle weakness, irregular heartbeat, and depression. 

Humans require a certain constant level of intake of sodium and chloride ions to maintain their vital concentrations in plasma and extracellular fluids. The daily requirement is about 5 g of NaCl an excessive intake is detrimental to health. 

Diet—Average Americans consume about 10 g of salt each day. This amount translates into 4,000 mg of sodium daily— considerably more than the upper limit of 500 mg currently recommended by the National Research Council. Furthermore, under ordinary circumstances the body requires only 115 mg of sodium daily and under conditions of profuse sweating only 780 mg daily. So, while no direct evidence links salt intake to the development of hypertension, there are no known benefits to the healthy person of excessive salt consumption. Moreover, it is reasonable to assume that a voluntary lowered salt intake will reduce the risk of developing high blood pressure in the 10 to 30% of all Americans born with a genetic predisposition to hypertension. In addition, a 1 1 ratio of sodium and potassium intake may be somewhat protective. 

In summary, lOOg of fish affords low levels of sodium and medium-to-high levels of all the remaining dietary minerals. In fact, it can contribute 50-100% of the total daily requirements of magnesium, phosphorus, iron, copper, selenium, and iodine. A Mediterranean diet, rich in fatty fish and all kinds of shellfish, can lead to an overall balanced mineral supply, which may well reach over 20% of daily requirements of phosphorus, iron, selenium, and iodine. 

Sodium Intake. Where salt is readily available, most of the world s population chooses to consume about 6,000—11,000 mg of salt or sodium chloride a day so that average daily sodium intake from all sources is 3,450 mg (8,770 mg NaCl) (13). The U.S. EDA s GRAS review puts the amount of naturally occurring sodium in the American diet at 1000—1500 mg/d, equivalent to the amount of sodium in approximately 2500—3800 mg NaCl. Thus the average daily intake of NaCl from food-grade salt used in food processing (qv) and from salt added in cooking or at the table is from 4960—6230 mg NaCl. The requirement for salt in the diet has not been precisely estabUshed, but the safe and adequate intake for adults is reported as 1875—5625 mg (14). The National Academy of Sciences recommends that Americans consume a minimum of 500 mg/d of sodium (1250 mg/d salt) (6,15). 

The body s normal daily sodium requirement is 1.0 to 1.5 mEq/kg (80 to 130 mEq, which is 80 to 130 mmol) to maintain a normal serum sodium concentration of 136 to 145 mEq/L (136 to 145 mmol/L).15 Sodium is the predominant cation of the ECF and largely determines ECF volume. Sodium is also the primary factor in establishing the osmotic pressure relationship between the ICF and ECF. All body fluids are in osmotic equilibrium and changes in serum sodium concentration are associated with shifts of water into and out of body fluid compartments. When sodium is added to the intravascular fluid compartment, fluid is pulled intravascularly from the interstitial fluid and the ICF until osmotic balance is restored. As such, a patient s measured sodium level should not be viewed as an index of sodium need because this parameter reflects the balance between total body sodium content and TBW. Disturbances in the sodium level most often represent disturbances of TBW. Sodium imbalances cannot be properly assessed without first assessing the body fluid status. 

The body s normal daily potassium requirement is 0.5 to 1 mEq/kg (0.5 to 1 mmol/kg) or 40 to 80 mEq (40 to 80 mmol) to maintain a serum potassium concentration of 3.5 to 5 mEq/L (3.5 to 5 mmol/L). Potassium is the most abundant cation in the ICF, balancing the sodium contained in the ECF and maintaining electroneutrality of bodily fluids. Because the majority of potassium is intracellular, serum potassium concentration is not a good measure of total body potassium however, clinical manifestations of potassium disorders correlate well with serum potassium. The acid-base balance of the body affects serum potassium concentrations. Hyperkalemia is routinely seen in... 

In patients with peritonitis, hypovolemia is often accompanied by acidosis, so large volumes of a solution such as lac-tated Ringers may be required initially to restore intravascular volume. Maintenance fluids should be instituted (after intravascular volume is restored) with 0.9% sodium chloride and potassium chloride (20 mEq/L) or 5% dextrose and 0.45% sodium chloride with potassium chloride (20 mEq/L). The administration rate should be based on estimated daily fluid loss through urine and nasogastric suction, including 0.5 to 1.0 L for insensible fluid loss. Potassium would not be included routinely if the patient is hyperkalemic or has renal insufficiency. Aggressive fluid therapy often must be continued in the postoperative period because fluid will continue to sequester in the peritoneal cavity, bowel wall, and lumen. 

Electrolytes that are included routinely in PN admixtures include sodium, potassium, phosphorus (as phosphate), calcium, magnesium, chloride, and acetate. When determining electrolytes in PN admixtures, the patient s renal function always must be taken into account. Typical daily electrolyte maintenance requirements for adults with normal renal function are listed in Table 97-3. 

New York City s 7.9 million people in 1978 had a daily per capita consumption of 656 liters of water. How many metric tons (103 kg) of sodium fluoride (45% fluorine by weight) would be required per year to give this water a tooth-strengthening dose of 1 part (by weight) fluorine per million parts water The density of water is 1.000 g/cm3, or 1.000 kg/L. 

Infants with salt-wasting CAH require mineralocorticoid replacement therapy, usually with fludrocortisone (9oc-fluorohydrocortisone). In addition, they require sodium chloride (1-2 g/day) since the sodium content of both breast milk and common infant formulas is only sufficient to meet the requirements of healthy infants (White and Speiser, 2000). Older children often acquire a taste for salty foods and do not require daily sodium chloride tablets. Plasma renin activity may be used to monitor mineralocorticoid and sodium replacement. 

Urea and electrolytes Sodium, potassium, urea and creatinine require close daily monitoring. The aim is to normalise and to avoid, in particular, drops in electrolytes such as sodium and potassium due to diuretic therapy. Other electrolytes such as magnesium and calcium may need to be checked regularly. 

Saturated Potassium Iodide Solution Dissolve excess potassium iodide in freshly boiled water. Excess solid must remain. Store this solution in the dark. Test it daily by adding 0.5 mL to 30 mL of the Acetic Acid-Chloroform Solution, then add 2 drops of starch TS. If the solution turns blue, requiring more than 1 drop of 0.1 N sodium thiosulfate to discharge the color, prepare a fresh solution. 

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