Potassium intake

The distal tubules secrete 90% to 95% of the daily dietary intake of potassium. The fractional excretion of potassium (FEk) is approximately 25% with normal kidney function.29 The GI tract excretes the remaining 5% to 10% of dietary potassium intake. Following a large potassium load, extracellular potassium is shifted intracellularly to maintain stable extracellular levels. 

Hyperkalemia is defined as a serum potassium concentration greater than 5 mEq/L (5 mmol/L). Manifestations of hyperkalemia include muscle weakness, paresthesias, hypotension, ECG changes (e.g., peaked T waves, shortened QT intervals, and wide QRS complexes), cardiac arrhythmias, and a decreased pH. Causes of hyperkalemia fall into three broad categories (1) increased potassium intake (2) decreased potassium excretion and (3) potassium release from the intracellular space. 

Antioxidants in fruits and vegetables including vitamin C and (3-carotene reduce oxidative stress on bone mineral density, in addition to the potential role of some nutrients such as vitamin C and vitamin K that can promote bone cell and structural formation (Lanham-New 2006). Many fruits and vegetables are rich in potassium citrate and generate basic metabolites to help buffer acids and thereby may offset the need for bone dissolution and potentially preserve bone. Potassium intake was significantly and linearly associated with markers of bone turnover and femoral bone mineral density (Macdonald and others 2005). 

Macdonald H, New S, Fraser W, Campbell M and Reid D. 2005. Low dietary potassium intakes and high dietary estimates of net endogenous acid production are associated with low bone mineral density in premenopausal women and increased markers of bone resorption in postmenopausal women. Am J Clin... 

Hyperkalemia develops when potassium intake exceeds excretion or when the transcellular distribution of potassium is disturbed. 

Primary causes of true hyperkalemia are increased potassium intake, decreased potassium excretion, tubular unresponsiveness to aldosterone, and redistribution of potassium to the extracellular space. 

It is well recognized that interrelations exist. How much sodium one needs depends upon his potassium intake his calcium needs are determined in part by his phosphate intake his need for a specific amino acid may be determined in part by the amount of the other amino acids that he gets (they can interfere with each other s utilization). Only by further experimentation can we determine how important antagonisms and other interrelations are in human nutrition. If highly important, they will seriously complicate the picture but will not change its basic outlines. 

Pharmacokinetics Normally about 80% to 90% of potassium intake is excreted in urine with the remainder voided in stool and, to a small extent, in perspiration. Kidneys do not conserve potassium well during fasting or in patients on a potassium-free diet, potassium loss from the body continues, resulting in potassium depletion. A deficiency of either potassium or chloride will lead to a deficit of the other. 

Hyperkalemia Carefully evaluate patients for possible fluid and electrolyte balance disturbances. Hyperkalemia may occur with impaired renal function or excessive potassium intake and can cause cardiac irregularities that may be fatal. Ordinarily, do not give potassium supplements with spironolactone. 

This consists of weight reduction, physical activity, moderation of dietary sodium and high dietary potassium intake. Implementation of lifestyle modifications should not delay the start of effective antihypertensive drug therapy. Patients with renal insufficiency with proteinuria greater than 1 g/day should be treated to a BP goal of 125/75 mmHg ... 

Because the actions of triamterene and amiloride are independent of plasma aldosterone levels, their prolonged administration is likely to result in hyperkalemia. Both amiloride and triamterene are contraindicated in patients with hyperkalemia. Triamterene should not be given to patients with impaired renal function. Potassium intake must be reduced, especially in outpatients. A folic acid deficiency has been reported to occur occasionally following the use of triamterene. 

In terms of mineral content, potato is best known as an important source of dietary potassium, which plays a fundamental role in acid-base regulation and fluid balance and is required for optimal functioning of the heart, kidneys, muscles, nerves, and digestive systems. Health benefits of sufficient potassium intake include reduced risk of hypokalemia, osteoporosis, high blood pressure, stroke, inflammatory bowel disease (IBD), kidney stones, and asthma. A high intake of potassium and low intake of sodium have been hypothesized to reduce the risk of stroke (Larsson et al., 2008 Swain et al., 2008). However, most American women 31-50 years old consume no more than half of the recommended amoimt of potassium and men s intake is only moderately higher (lOM, 2004). 

According to the FDA Total Diet Study, in which dietary sodium and potassium intakes of three age groups of Americans were estimated from 1977 through 1980, cow s milk supplied 32 to 39% of the total sodium intake for infants, whereas the percentage for toddlers was much lower, 12 to 14% (Shank et al. 1982). Dairy products contributed about 10% of the sodium in the total diet consumed by adults. Data obtained from the National Health and Nutrition Examination Survey (HANES II) 1976-1980 (Carroll et al. 1983) reveal that the median daily consumption of sodium found naturally in food and added during... 

Thiazide diuretics act upon the kidneys to stimulate urine production. This can also result in excessive loss of sodium chloride, bicarbonate, and potassium ions. It is common practice to increase supplemental potassium intake during Thiazide use. Normal reference ranges for potassium are ... 

In 1991, University of Pennsylvania researchers found that just ten days of potassium restriction resulted in rises in blood pressure, whether one had normal or elevated blood pressure to begin with. A twelve-year study of California adults suggested that high potassium intake protects against stroke, the worst result of hypertension. For men in that study, those with low potassium intake had 2.6 times more stroke risk than did men with high consumption of potassium-rich foods. For women, low intake multiplied the risk by nearly five times. 

Surely, in that listing, there must be some foods that start your mouth watering Why not add some of them to your shopping list right now And be sure to include some dried fruits, such as apricots and raisins that you can keep in the car, your purse, or the office for handy, healthy snacks. Shoot for a potassium intake of at least 3,500 mg daily, ideally 4,700 mg (4.7 grams/120 mmol). 

Maintaining a good dietary potassium intake (fruits, fruit juices, vegetables)... 

The minimal requirement for potassium is alrout 1.6 to 2.0 g/day. Fruits and vegetables contain Wgh levels of potassium. Persons who consume large amounts of these foods may have a potassium intake of 8 to 11 g/day. A more typical intake is 2.5 g/day Human milk contains about 12 mM potassium. 

Mickelsen, O, Makdani, D., Ciil, f. L, and Prank, R. L. (1977). Sodium and potassium intakes and excretions of normal men consuming sodium chloride ora hi mixture of sodium and potassium chlorides. Am. j. CUn. Nntr. 30, 203i3-204(. ... 

Hoibrook, J. T, Patterson, K. Y Bodner, J. E., Douglas, L. W., til on, C Kelsey, J. L., Mertz, W., and Smith, J. C, (19S4). Sodium and potassium intake and balance in adults consuming self- seiected diets. Atti.. Clin. Widr 40, 786-793. 

Amiloride is a therapeutic option in reducing potassium losses in patients receiving amphotericin. When it was given to 19 oncology patients with marked amphotericin-induced potassium depletion mean serum potassium concentrations increased in the 5 days before and after administration (from 3.4 to 3.9 mmol/1) (8). There was also a trend toward reduced potassium supplementation (48 versus 29 mmol/day). Adverse reactions were limited to hyperkalemia in two patients who took amiloride 20 mg/day and a high potassium intake. 

Gossypol causes potassium loss, perhaps by a direct toxic effect on the renal tubules (3), which can cause renal tubular acidosis (4). Hypokalemic paralysis (5) has been reported in about 1 % of 8806 volunteers and in China was more common in areas of low dietary potassium intake, such as Nanjing (6) muscular weakness and severe fatigue are prodromal signs (7). Neither potassium supplementation nor triamterene prevented potassium loss in patients taking gossypol (8). 

Bunchman TE, Wood EG, Schenck MH, Weaver KA, Klein BE, Lynch RE. Pretreatment of formula with sodium polystyrene sulfonate to reduce dietary potassium intake. Pediatr Nephrol 1991 5(l) 29-32. 

Simple dietary measures provide adequate potassium intake, and it is questionable whether for most patients potassium supplementation in any pharmaceutical form is necessary, as opposed to the use of potassium-sparing drugs. 

Schim van der Loeff HJ, Struck van Schijndel RJ, Thijs LG. Cardiac arrest due to oral potassium intake. Intensive Care Med 1988 15(l) 58-9. 

The recommended daily allowance for dietary potassium intake is approximately 50 mEq/day. Potassium is found in abundance in fruits, vegetables, and meats. The typical American ingests approximately 50 to 150 mEq of potassium daily." Nearly all of this is absorbed, with only 10 to 20 mEq eliminated in feces. The amount eliminated in the feces increases, however, in patients with diarrhea, and perhaps in those with underlying chronic kidney disease (CKD).5... 

Hyperkalemia develops when potassium intake exceeds excretion (i.e., elevated total body stores), or when the transcellular distribution of potassium is disturbed (i.e., normal total body stores). Generally, there are four primary causes of true hyperkalemia (1) increased... 

Hyperkalemia Associated with Increased Potassium Intake... 

The kidneys excrete 80% of the daily potassium intake. Therefore when the kidney is unable to excrete potassium appropriately, as in acute renal failure and CKD, potassium is retained and often results in hyperkalemia. Moreover, many drugs can inhibit the kidney s ability to excrete potassium by inhibiting aldosterone and thus contribute to an increase in serum potassium levels. 

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