For the second time in a week, scientists are warning us that what we’re eating is killing us.

This time it's salt.

Cardiologists gathered for a meeting in New Orleans report that excessive salt in our diets contributed to a stunning 2.3 million deaths around the world in 2010 – including fatal heart attacks, strokes and other heart-related diseases.

They say that these unnecessary deaths represent 15 per cent of all deaths that year.

“We found overall, 2.3 million deaths in 2010 around the world were due to eating too much salt,” Dr. Dariush Mozaffarian, of the Harvard School of Public Health, told CTV News. “The magnitude of the impact was really surprising.”

Earlier this week, Harvard researchers revealed that sugary drinks -- such as soft drinks, juices and sports drinks -- were major factors behind spiking rates of obesity and diabetes, resulting in an estimated 180,000 premature deaths around the globe each year.

For the salt study, researchers analyzed more than 240 surveys of sodium intake in 50 countries between 1990 and 2010. They then looked at studies that measured how high amounts of sodium affect blood pressure and the risk of cardiovascular disease, which includes both heart disease and stroke.

They concluded nearly 1 million of the deaths they attributed to excess salt in peoples’ diets came prematurely – meaning in those younger than 69 years. They also found:

  • 60 per cent of the deaths occurred in men, 40 per cent were in women.
  • Heart attacks caused 42 per cent of the deaths;
  • strokes caused 41 per cent;
  • the remainder resulted from other types of cardiovascular disease.
  • 84 per cent of the deaths due to too much sodium were in low and middle-income countries.

Dr. Bob Reid, a researcher with the University of Ottawa Heart Institute, says the study is one with an important message.

“The connection they are trying to draw is that sodium affects our blood pressure. And how high our blood pressure is affects our risk of heart disease and stroke,” he told CTV News. “It helps quantify the total deaths, and it is a large number.”

Health Canada recommends that Canadians aim for about 1,500 milligrams of sodium a day, and no more than 2,300 milligrams -- the equivalent of about a teaspoon of salt. But research shows the average Canadian consumes 3,400 milligrams per day.

Dr. Reid says it’s clear that we need to be reminded to avoid salt whenever we can.

“We have to become much better at preventing disease… and this is an example of that,” he said.

The Salt Institute objects to the study, calling it misleading and the "latest example of statistical abuse that distorts the health debate."

They note that the researchers didn’t track actual deaths; they simply used a statistical model to estimate the deaths – a model that the institute calls “highly flawed.”

“The fact that the authors of this study and the American Heart Association chose to represent this shoddy modeling exercise as evidence of authentic cardiovascular mortality figures reveals an agenda far more rooted in sensationalist politics than in science,” the group said in a statement to CTV News.

"This latest statistical study is not rooted in reality, but is based upon the small, potential reductions in blood pressure that may be experienced by some individuals if they cut out three-quarters of their salt -- a challenge repeatedly shown to be impossible everywhere in the world."

With a report from CTV medical specialist Avis Favaro and producer Elizabeth St. Philip