Potassium is an essential mineral that regulates the heart rate and helps muscles to contract. Potassium is found in many different types of foods, including avocados, bananas, potatoes, chicken, salmon and citrus juice. In order for the body to use potassium appropriately, it must be absorbed during the digestive process. The absorption of potassium takes place in the intestinal tract, and factors that negatively affect potassium absorption harm your health.
Absorption occurs as a nutrient passes through the walls of the intestine into the bloodstream or lymphatic system. Absorption may be considered to be active or passive, the former type of absorption requires energy to occur, while the latter form does not. Potassium absorption occurs in the portions of the intestine called the ileum and the jejunum -- the final two of three sections in the small intestine -- and it is a passive process, which means that potassium diffuses into your body on its own.
Using laxatives may affect how the body absorbs potassium, which could lead to low potassium levels. Laxatives increase the amount of fluid in the stool and they may stimulate the bowel to accelerate the process of moving stool out of the body. This process could cause you to lose potassium before it is absorbed. Low levels of potassium are associated with weakness, muscle cramps and irregular heartbeat.
Some people who have health conditions that affect the bowel may need to take in extra potassium because it could become depleted before it is absorbed. For people with ulcerative colitis, potassium absorption may be lowered with chronic diarrhea, in which the potassium is excreted from the body before it has a chance to be absorbed. Additionally, steroid medications used to treat gastrointestinal conditions may force the body to excrete more potassium before it can be absorbed, resulting in potassium losses.
Normally, you absorb potassium at approximately the rate you excrete it in your urine, which maintains a consistent balance in the body. Potassium supplements may be necessary if you need extra nutrition or you have problems absorbing potassium. They are designed to support potassium absorption to help keep levels within the average range. For example, potassium chloride supplements are available in extended-release tablets that allow for slow, consistent absorption of potassium when overall levels in the body are low. If you have low potassium, talk with your doctor about taking supplements to correct the condition.