The trial data are nonetheless insufficient for setting an EAR, which would require data at multiple intake levels so that a level could be derived that would reduce blood pressure, mitigate salt sensitivity, or decrease the risk of kidney stones in 50 percent of individuals evaluated. Still, it is possible to set an AI at 4.7 g (120 mmol)/day using available data.

While the AI is set at the same intake level for men and women, it is recognized that differences in body size, body composition, and caloric intake may affect requirements. However, presently available data are insufficient to set gender-specific requirements. Since most of the studies used to derive the AI included both men and women and did not report findings on the basis of these characteristics, it is thus appropriate at this point to set the recommended intake at the same level of intake for both.

It should be recognized that the studies used to set the AI were conducted in the setting of a high sodium intake (2.7 to 5.7 g [117 to 13 mmol]/day), which greatly exceeds the AI of 1.5 g (65 mmol)/ day of sodium. While it is plausible that the AI for potassium might be lower in the setting of a reduced sodium intake, data are insufficient to set this level.

Summary. The AI for potassium is set at 4.7 g (120 mmol)/day based on blunting the severe salt sensitivity prevalent in African-American men and decreasing the risk of kidney stones, as demonstrated in a 3-year double-blind controlled study. Blood pressure studies in nonhypertensive individuals (Table 5-3) are supportive of this level of intake as a means to lower blood pressure. Epidemiological studies also suggest that higher levels of potassium intake from foods are associated with decreased bone loss. It is important to note that the beneficial effects of potassium in these studies appears to be mainly from the forms of potassium that are associated with bicarbonate precursors—the forms found naturally in foods such as fruits and vegetables.