Two weeks later, another research group challenged the findings, saying a reanalysis of the same data did indeed show that sodium raises blood pressure, which in turn raises the risk of stroke and heart attacks. The more people can lower their daily salt intake, the more their blood pressure will fall, which is a good thing, the second group argued in a commentary published in the medical journal the Lancet.
The debate, says Nissen, is not over whether salt is bad for those with high blood pressure, heart disease or kidney disease. The question is, should restricting salt be a blanket recommendation for everyone, even those with normal blood pressure?
If you ask federal health officials, the answer is unequivocally yes — everyone can benefit by reducing their salt, especially older Americans.
The government's 2010 dietary guidelines for Americans recommend limiting total salt intake from all sources to 1,500 mg a day (less than a teaspoon) for people 51 and older, African Americans and those with high blood pressure, diabetes or chronic kidney disease. Most Americans now consume more than twice that much.
If nothing else, the guidelines advise, consumers should at least look at the food labels of the products they buy and pick the brands that have less sodium. Americans get nearly 80 percent of the salt they consume from processed and restaurant food, not from the salt they add when they're cooking at home.
The American Heart Association is even more adamant, issuing a "call to action" this past January for consumers, health professionals, the food industry and the government to "intensify efforts to reduce the amount of sodium Americans consume daily."
The association goes further than the government, recommending that all adults, regardless of age, consume no more than 1,500 mg of sodium to reduce the risk of stroke, heart attacks and kidney disease. Doing this, the association says, will save on health care costs and save lives.
But then a recent study of 12,000 adults by researchers with the federal Centers for Disease Control and Prevention, published in the Archives of Internal Medicine, found that the ratio of sodium to potassium may be a more important factor in determining risk of death than sodium alone. Researchers found that those who ate a high-salt, low-potassium diet — meaning heavy in processed and restaurant food — had a 50 percent higher risk of death. Those who had a higher potassium intake (typical of fresh foods) had a lower risk of death.
Obviously, for those who have high blood pressure, heart or kidney disease, "restricting salt is the right thing," Nissen says. Following a low-salt diet can help them avoid having to take additional medicine, which can have side effects, he explains.
More importantly, for those with congestive heart failure, cutting back on salt "will keep you out of the hospital."
But for older Americans with normal blood pressure, sticking to a low-salt diet can be tough, especially because we've all grown accustomed to the salt levels in packaged and restaurant food, so low-salt foods taste bland. Campbell's soup recently announced that they were adding the salt back into their line of low-sodium soups because the soups weren't selling.