This article appears in Fall Healthy Living 2018.
Please pass the salt and start the conversation. Some new research finds average salt consumption is safe for heart health, but other experts disagree.
Sodium — the key element in table salt — is essential for life and makes food tastier, yet the Centers for Disease Control and Prevention report that most Americans consume too much of it and that it’s connected to high blood pressure and related health issues.
Recommendations from the American Heart Association advise restricting sodium intake to less than 2.3 grams a day (about 1 teaspoon of salt) with an ideal limit of 1.5 grams a day. Most Americans consume more: on average, 3.4 grams a day, according to the CDC.
New research from McMaster University in Ontario, Canada, however, finds that an increased salt intake isn’t unhealthy except for those who eat more than 5 grams a day, the equivalent of 2.5 teaspoons of salt. Published in The Lancet, the research also shows that people who consume higher amounts of salt can offset any negative effects by adding fruits, vegetables, dairy, potatoes and other potassium-rich foods to their diets.
About the study
The large study followed 94,000 people, ages 35 to 70, for an average of eight years in communities from 18 countries and found a risk of cardiovascular disease and stroke only where the average sodium intake is greater than 5 grams a day.
Focusing on sodium intake and cardiovascular disease in an earlier study, “we found that both low (below 3 grams a day) and high (above 5 grams a day) of sodium is associated with a higher risk of cardiovascular events or death. So there is a sweet spot in the middle (3 to 5 grams a day of sodium) associated with the lowest risk of harm,” said Dr. Andrew Mente, first author of the study and researcher at McMaster University’s Population Health Research Institute.
The key seems to be potassium.
“In our data, we see that higher potassium has beneficial associations with each health outcome, including heart attacks, stroke, cardiovascular disease and total mortality. This would suggest not only a potassium effect per se, but also that potassium is a marker of an all-around healthy diet,” Mente said.
Potassium is found in fruits, vegetables, nuts and dairy products.
“These are foods that are generally beneficial and can be included in an all-around healthy eating pattern,” Mente said. “So follow an all-around balanced diet that contains plenty of fruit, vegetables, nuts and dairy, and don’t worry about sodium restriction.”
“I’m not convinced,” said Dr. Paul K. Whelton, professor of public health at Tulane University and contributor to many major dietary guidelines. The findings are unexpected, and that means responsible people should step back and ask questions about how it is biologically possible, he said.
“The one thing we know is that high blood pressure is related to cardiovascular complications. The second thing we know is that lowering blood pressure reduces the risk of cardiovascular complications. We also know that higher sodium intake is closely related to higher blood pressure. We know this. Everyone agrees. If you lower sodium, you lower blood pressure and you lower the risk of cardiovascular complications,” Whelton said.
“The study has many problems. The most important is their measurement of sodium, which is fundamentally flawed,” said Lawrence J. Appel, professor of medicine at Johns Hopkins University School of Medicine and director of the Welch Center for Prevention, Epidemiology and Clinical Research. “Elevated salt intake raises blood pressure, which is the leading cause of preventable mortality worldwide and also a major cause of substantial morbidity, particularly stroke.”
Before changing your diet, talk to your doctor.