More than 1.6 million cardiovascular-related deaths per year can be attributed to sodium consumption above the World Health Organization’s recommendation of 2.0 g (2,000 mg) per day, researchers have found in a new analysis evaluating populations across 187 countries. The findings were published on August 14th in The New England Journal of Medicine.
“We found that four out of five global deaths attributable to higher than recommended sodium intakes occurred in middle- and low-income countries,” said John Powles, M.B., B.S., last author and honorary senior visiting fellow in the Department of Public Health and Primary Care at the University of Cambridge. “Programs to reduce sodium intake could provide a practical and cost effective means for reducing premature deaths in adults around the world.”
The researchers collected and analyzed existing data from 205 surveys of sodium intake in countries representing nearly three-quarters of the world’s adult population, in combination with other global nutrition data, to calculate sodium intakes worldwide by country, age, and sex. Effects of sodium on blood pressure and of blood pressure on cardiovascular diseases were determined separately in new pooled meta-analyses, including differences by age and race. These findings were combined with current rates of cardiovascular diseases around the world to estimate the numbers of cardiovascular deaths attributable to sodium consumption above 2.0 grams per day.
The researchers found the average level of global sodium consumption in 2010 to be 3.95 g per day, nearly double the 2.0 g recommended by the World Health Organization. All regions of the world were above recommended levels, with regional averages ranging from 2.18 g per day in sub-Saharan Africa to 5.51 g per day in Central Asia. In their meta-analysis of controlled intervention studies, the researchers found that reduced sodium intake lowered blood pressure in all adults, with the largest effects identified among older individuals, blacks, and those with pre-existing high blood pressure.
“These 1.65 million deaths represent nearly one in 10 of all deaths from cardiovascular causes worldwide. No world region and few countries were spared,” said Dariush Mozaffarian, dean of the Friedman School of Nutrition Science and Policy at Tufts University, who led the research while at the Harvard School of Public Health. Mozaffarian chairs the Global Burden of Diseases, Nutrition, and Chronic Disease Expert Group, an international team of more than 100 scientists studying the effects of nutrition on health and who contributed to this effort. “These new findings inform the need for strong policies to reduce dietary sodium in the United States and across the world.”