Food chloride distribution in nature and its relation to sodium content

Because of growing interest in the biological and clinical effects of dietary chloride as the anion accompanying the dietary cation sodium and because the standard food composition tables used in the United States to estimate sodium content do not contain data on chloride content, we analyzed the nutrient data base of the English workers Paul and Southgate, which contains an extensive listing of both chloride and sodium contents in foods. To examine food chloride distribution in nature, we focused on the uncooked, unadulterated, discrete, primitive foods in the data base (no. = 216 food items). The findings indicate the existence of both a large variability of chloride content among foods and a high degree of coupling of chloride with sodium. The contents of chloride and sodium varied over a similarly large range (coefficients of variation, 229% vs. 263%), differed very little from each other on the average (less than 20%), and correlated (r = 0.84, p less than 0.001) to the extent that greater than two-thirds of the overall variation of chloride content was linked to that of sodium content. Those findings accord with the often posited but untested assertion that the chloride content of foods approximates and parallels that of sodium.(ABSTRACT TRUNCATED AT 250 WORDS)