According to a new report published in the July 11 issue of Archives of Internal Medicine, one of the JAMA/Archives journals, people with a high sodium intake are at an increased risk of cardiovascular disease (CVD) and mortality. The risk increases significantly if high sodium intake is coupled with a low potassium intake.
As mentioned in the background information of the article, literature review strongly suggests possible associations between hypertension and high sodium intake or low potassium intake. The authors state,
"Recently, several studies suggested that the ratio of sodium to potassium intakes represented a more important risk factor for hypertension and CVD than each factor alone." "Examining the joint effects of sodium and potassium intakes on CVD risk is particularly important because most of the U.S. population consumes more sodium and less potassium daily than recommended."
Researcher Quanhe Yang, Ph.D., who serves at the Centers from Disease Control and Prevention, Atlanta, and his colleagues, used data from the Third National Health and Nutrition Examination Survey Linked Mortality File. A cohort of 12,267 based on dietary information, demographic characteristics, health history and mortality status was selected for the study. The analysis of data for consumption of sodium-potassium, along with its ratio was conducted. Data analysis was also performed to further understand the relationship of these variables and the risk of death due to CVD, ischemic heart disease (IHD) or any other cause (all-cause mortality).
The results for a follow up period of 14.8 years revealed, amongst all, 2,270 participants had died; out of which 825 deaths were related to CVD and 433 to IHD. Scientists also demonstrated that male sex, younger age, smoking and ethnic background were some additional characteristics related to higher sodium-potassium ratio. On variable adjustments, higher intake of sodium resulted in increased all-cause mortality while lower mortality risk was observed with higher intake of potassium. Researchers reported that a higher sodium-potassium ratio in participants significantly elevated the risk of CVD and IHD.
The authors conclude,
"In summary, our findings indicate that higher sodium-potassium ratio is associated with significantly increased risk of CVD and all-cause mortality in the general US population. Public health recommendations should emphasize simultaneous reduction in sodium intake and increase in potassium intake."
Commentary: Sodium and Potassium Intake - Mortality Effects and Policy Implications
Commenting upon the findings of Yang and colleagues, a team of researchers from the New York City Department of Health and Mental Hygiene, Lynn D. Silver, M.D., M.P.H., and Thomas A. Farley, M.D., M.P.H., write,
"This article strengthens the already compelling evidence of the relationship between sodium intake and mortality".
They believe that large scale efforts are needed to decrease the dietary intake of sodium and to increase the potassium consumption.
Silver and Farley suggest that large scale efforts must continue and that addition of potassium content be done to the Nutrition Facts panels of food labels. They also stress on creation of a nutritional database which will enable the public and researchers to better understand the nutrient content of the U.S. food supply. They conclude,
"It is crucial, that we understand the interplay of sodium and potassium in the diet and how to optimize intake in an increasingly processed food supply without generating harm."
Source: Archives of Internal Medicine
Written by Anne Hudsmith