The paper, published in the New England Journal of Medicine (NEJM) on Thursday, found that the average consumption of salt across the globe was 3.95gm per day , nearly double the 2gm recommended by the World Health Organization.
A separate Indian study released a few days ago--the INDIAB study of the Indian Council for Medical Research--found that the mean salt intake in urban India was 7.6gm per day , much higher than the global mean.
"It is well known that salt or sodium is a risk factor for heart disease and stroke," said endocrinologist Dr Shashank Joshi, one of the lead authors of the INDIAB study .
Considering that one in four Indian adults suffers from high blood pressure, one can gauge the extent of heart problems caused by salt.
The highlight of NEJM's study , conducted by a 100-member team of academicians led by Tufts University , is that it's the first to quantify the effect of excess sodium on cardiovascular diseases. The final conclusion was that in 2010 alone, around 1.65 million across the world suffered fatal heart problems aggravated by their high sodium intake.
To arrive at the conclusion, the study--funded by the Bill & Melinda Gates Foundation--analyzed existing data from 205 surveys of sodium intake in 66 countries. The effects of sodium on blood pressure and of blood pressure on cardiovascular diseases were determined separately . The researchers then combined these findings with the current rates of cardiovascular diseases around 187 countries to estimate the number of cardiovascular deaths attributable to sodium consumption above 2gm per day .
"This important study reiterates that excess salt intake is equivalent to tobacco intake in terms of human disease and death. India ranks high on the list of countries with excess salt intake and resultant cardiovascular disease and deaths," said senior Delhi-based endocrinologist Dr Anoop Misra. He felt that a reduction in salt intake is not possible without legal restrictions and policy changes. "Salt restriction should be at the top of health policy planning to contain hypertension and heart disease," he added.
The INDIAB study on the prevalence of diabetes and hypertension in India published two weeks ago found that Indians have a "salt-preponderance". "We crave salt. We not only reach for packed namkeen stuff and dishes high on salt, we also take hidden salt in pickles, papads, etc," said Joshi.
The explosion of hypertension in the country is higher than diabetes.
"The number of Indians suffering stroke is rising. One of the causes is our high salt intake," said Joshi.
The NEJM study found that four out of five global deaths attributable to higher than recommended sodium intakes occurred in middleand low-income countries. The research team also said the 1.65 million deaths meant that nearly one in 10 of all deaths from cardiovascular causes worldwide was due to higher salt ingestion. It concluded that strong policies are needed to reduce dietary sodium across the world.
Maha On Sodium High The INDIAB study of the Indian Council of Medical Research (ICMR) released data last fortnight, showing the mean salt intake in urban areas was significantly higher than that in the rural areas (7.6gm per day against 6.8gm per day).
The mean salt intake was highest in Chandigarh (8.3gm per day), followed by Maharashtra (7.2gm per day), Tamil Nadu (6.8gm per day) and Jharkhand (5.9gm per day).