Doctors and nutritionists know that too much salt can kill.
Now we are learning that lowering the amount of salt we eat every day might save our lives if we make enough of an adjustment in time.
Pamela Coxson, a mathematician in the department of Internal Medicine at the University of California San Francisco Medical Center, was lead author in a new “study” just published in the journal Hypertension, which examines the effects of lowering our sodium intake on our risk of dying.
At the request of the Centers for Disease Control, the report was a collaborative effort between researchers at UCSF, Harvard and Simon Fraser University in Canada. Actually, this new report isn’t a study in the conventional sense but a computer model which utilizes previous research on the effects of dietary sodium on blood pressure and the heart and the risk of death. The model predicts the effects of reduction of salt intake to safer levels in terms of lives saved.
“These simulated outcomes represent our best effort to compare the implications of three different sources of evidence for benefits of sodium reduction in the U.S. population,” Coxson told Fox News. “Evidence for the effects of dietary sodium comes from basic science and clinical and observational trials. Our computer simulations do not add to this evidence base, but rather they help us to assess the magnitude of a studied effect if the benefits accrued (by cutting sodium intake) in a similar way to the U.S. population.”
Coxson and the other analysts found the benefits of sodium reduction were greatest in the elderly, though still substantial in those less than 65.
According to the American Heart Association, the average American takes in about 3,000 to 3,600 mg of sodium per day, yet we actually need less than 1,500 mg per day. To give you an idea how much sodium that is; a teaspoon of salt has about 2,300 mg of sodium.
Whereas Americans get 25 percent of our salt from the salt shaker, the majority comes from the processed foods (including breads, soups, canned meats, etc.) that we eat every day. We could cut down dramatically on our sodium intake by simply increasing the fruits and vegetables in our diets and decreasing the amount of bread and meat.
The new computer model estimates that reducing sodium 40 percent over 10 years, from 3,600 mg per day to 2,200 mg per day, would save 500,000 American lives. If this dietary change could be adapted right away, the number of lives saved would be more than 700,000.
The mathematical projections in the study relied on three methods:
The first method, conducted by Nancy Cook at Harvard Medical School, was a projection of the cardiovascular disease benefits observed by reducing salt intake in the Trials of Hypertension Reduction study, where long term follow up found a 25 percent lower incidence of heart disease, strokes, and related deaths in patients with blood pressure that was high-normal.
The second and third methods assumed that dietary sodium reduction reduces blood pressure as reported in meta-analyses of the more than 20 trials of sodium reduction. The second method, led by Michel Joffres at Simon Fraser University, was based on studies of blood pressure lowering using diuretics (similar mechanism to dietary salt reduction).
The third method, let by Pamela Coxson at UCSF, used a large computer simulation of heart disease outcomes and the effects of blood pressure lowering on various high risk groups taken from the National Health and Nutrition Examination Survey.
All three methods predicted a similar dramatic benefit on death rates by reducing sodium in our diets. Though this “benefit” is just a mathematical projection, there is a good amount of science behind it.
We would be wise to change our diets starting now.
Marc Siegel, M.D. is a professor of medicine and medical director of Doctor Radio at NYU Langone Medical Center. He has been a medical analyst and reporter for Fox News since 2008.