Health Supplement

Selenium is a trace element found in soil, and is required in small amounts to maintain good health. It is essential for many body processes and is present in nearly every cell but especially in the kidneys, liver, spleen, testes, and pancreas.

Selenium supplements used to prevent certain types of cancer such as cancer of the cervix, rectum, ovaries, bladder, oesophagus, pancreas and liver. It is also being tested against leukaemia with the hope of promising results. Selenium can protect the heart, primarily by reducing the “stickiness” of the blood and decreasing the risk of clotting, in turn, lowering the risk of heart attack, and stroke.

Lack of selenium may lead to changes in fingernails, muscle weakness, and heart problems.

Selenium deficiency is rare, as most people get enough in their daily diets. However, if you were to be deficient symptoms would include muscular weakness and fatigue. Too much selenium on the other hand is possible. If you are taking a selenium supplement you should remember not to exceed 600mcg per day. Overdosing on selenium or selenium poisoning can cause depression, nausea and vomiting, nervousness and loss of hair and fingernails along with a breath odour.

Source:
http://www.nutritional-supplements-health-guide.com/benefits-of-selenium.html

http://www.drugs.com/cons/selenium-supplements.html

Potassium is a mineral that performs many functions in the body. Potassium has been shown to help maintain lower blood pressure. Potassium plays a key role in the function of nerve firing [an involuntary physiologic response to stimuli], and the contraction of muscles.
Potassium may help reduce muscle soreness that results from training. Any deficiency in potassium levels may result in decreased strength, and the early onset of exercise induced fatigue. Potassium helps to regulate water balance and is also needed for the synthesis of dietary proteins.

The most common use of potassium supplements is to make up for potassium depletion caused by diuretic drugs. These medications are often used to help regulate blood pressure, but by depleting the body of potassium, they may inadvertently make blood pressure harder to control.
For individuals using diuretics, supplemental potassium can help ensure adequate levels exist within the body for use in the above mentioned processes. Stable potassium levels are also associated with lower occurrences of type 2 diabetes.
Taking too much potassium can result in an upset stomach, flatulence, abdominal pain, diarrhea, vomiting, and burping. An excessive amount of potassium can result in a heart attack. A typical therapeutic dosage of potassium is between 10 and 20 meq, taken 3 to 4 times daily.

Source:
http://www.criticalbench.com/Potassium-Supplement-Review.htm

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