Rich Potassium Diet

Introduction

Potassium (K) is a cation present at 95% within the cells. It is an essential trace element, therefore NOT replaceable or synthesizable by the organism.

The body of an adult contains about 110-140g of potassium, or 1.6-2g of mineral per kg of body weight; of these, 5.9 g / l are found dissolved in intracellular fluids and only 137-215 mg / l are found in the extracellular fluid.

Potassium functions

Its homeostasis is closely linked to that of sodium (extracellular electrolyte) and is maintained above all thanks to the SODIUM-POTASSIUM pump. This trans-membrane structure represents a pathway for the passage of molecules against concentration gradient, useful for controlling osmotic pressure and acid-base balance.

The extracellular portion of potassium is involved in the transmission of nerve impulses, muscle contraction and blood pressure regulation.

NB. The amount of potassium in the body is directly proportional to the cell mass, therefore, its body detection is frequently used in the estimation of the individual lean mass.

Potassium regulation

The dietary intake of potassium (K) occurs above all in an easily absorbable ionic form at the level of the small intestine. Although the potassium excretion pathways are three: intestinal, urinary and with sweat, it is essential to point out that potassium, due to its importance in maintaining numerous physiological processes, is a trace element subject to the control of renal filtration; this means that, although more than significant dietary changes or physiological losses may occur, the homeostasis of this electrolyte is guaranteed by the balance of the relationship between glomerular filtration and tubular secretion.

Potassium in food and in the diet

Potassium is an almost ubiquitous trace element in food, drink and even water. In healthy subjects and with ordinary physical activity, more than the total intake of potassium in the diet, it would be appropriate to consider the potassium / sodium REPORT (K: Na), a parameter that seems decidedly higher (therefore BETTER) in fresh foods, not processed and not preserved (fruit, vegetables and fresh meat).

The intake of potassium with drinking water is variable (based on the quality of the water) but still not decisive with respect to food.

A sufficiently balanced and "average" diet rich in potassium brings from 3 to 5g / day, while its urinary excretion is around 2.3g / day. Knowing the mechanisms of renal potassium savings, which would drastically limit their elimination in case of need, these values suggest that a potassium intake of 3-5g / day can be more than sufficient for homeostatic maintenance of essential functions.

NB. The balance of potassium in athletes is completely outside the above values; we recall that, although it has been specified that NORMALLY the proportion of potassium eliminated with sweating can be defined as almost irrelevant, a sportsman (especially endurance) can be subjected to repeated changes in the water balance that reach 3-4% of his body weight . In this case it is essential to assess the extent of the total dietary intake of potassium and possibly draw up a diet rich in trace elements; it is also possible and sometimes desirable to use hydro-saline food supplementation.

hyperkalaemia

As anticipated, potassium is an almost ubiquitous mineral (found in many foods) but nevertheless represents one of the most used nutrients in food supplementation; this means that many subjects, with diet and supplements, take a higher potassium quota than their own needs. However, assuming that renal function is at least NORMAL, the pathological excess of potassium in the blood - defined as hyperkalemia or hyperkalemia - is unlikely to say the least. Potassium intoxication may occur in the clinic due to excessive enteral or parenteral administration at doses> 17.5 g / day (3 or 4 times the average dose).

NB. Acute hyperkalemia can cause cardiac arrest.

Hypokalemia

Potassium deficiency, better known as hypokalemia, can occur via the gastrointestinal tract in the event of prolonged vomiting, chronic diarrhea or laxative abuse, or via the urine through the abuse of diuretics, in the presence of some types of chronic nephropathy or metabolic disorders like diabetic acidosis. A similar disorder can induce electrical alterations of cell membranes resulting in: muscle fatigue, anorexia, nausea, inattention, apprehension, drowsiness and behavioral alterations.

NB. Hypokalaemia, in the most serious cases can give rise to fatal cardiac arrhythmias and ileus paralysis.

Diet rich in potassium and hypertension

Some studies have reported an inverse correlation between increased blood pressure and urinary potassium excretion. It seems that a diet rich in potassium is essential for maintaining sodium homeostasis; in fact, subjects who do not reach satisfactory dietary levels of food potassium are unable to effectively eliminate sodium compared to those who carry out a diet rich in this mineral.

Ultimately, a diet rich in potassium can: