Monday, August 29, 2016

Limits on Oral Potassium in tablets and capsules

The U.S. Food and Nutrition Board (FNB) has established an Adequate Intake (AI) of 4.7 grams/day of potassium in a healthy adult. A tolerable upper limit (UL) was not established for potassium since there was no evidence of adverse effects from a high level of potassium from foods consumed by healthy adults.

Potassium is a food substance and is affirmed as generally recognized as safe (GRAS) by the U.S. FDA (21 CFR 184.1622) (FDA, 2012a). In October 2000, food containing at least 350 mg potassium and 140 mg or less of sodium was approved by the FDA to have the following health claim on product labeling: "Diets containing foods that are good sources of potassium and low in sodium may reduce the risk of high blood pressure and stroke." (FDA, 2012b; NMCD, 2012).

Some experts suggest that a single dose of potassium should be limited to 500 mg, while a total of 1,500 mg daily is considered safe for general supplementation. This is well within the AI level.

The 99 mg. limit on potassium tablets and capsules is based on a remote risk of a pill damaging the intestinal wall if it releases its content slowly. That risk does not apply to liquid forms, or to powders that are mixed with liquids. While higher amounts are allowable, a long warning is required on all potassium products intended for oral ingestion providing 100 mg or more of the mineral in a capsule or coated tablet form: