By Dr Ananya Mandal, MD
A new study by federal government researchers shows that most Americans consume too much sodium, and new strategies and stronger efforts are needed to reduce the amount of dietary salt. Experts add that high levels of sodium consumption are associated with increased risk of high blood pressure, which can lead to heart disease and stroke.
In general, people aged 2 years and older should limit daily sodium intake to less than 2,300 milligrams (mg), according to the 2010 Dietary Guidelines for Americans. People who would benefit from reducing their sodium intake to less than 1,500 mg per day include those aged 51 years and older, blacks and anyone with high blood pressure, diabetes or chronic kidney disease. These groups account for 47.6 percent of all Americans aged 2 and older and the majority of adults.
The latest analysis of 2005-2008 data from 18,823 participants in the U.S. National Health and Nutrition Examination Survey found that 98.6 percent of Americans who should reduce their daily sodium intake to 1,500 milligrams, and 88.2 percent of those who should reduce their intake to less than 2,300 mg per day, consume more than those amounts. The study is published in the Oct. 21 issue of the Morbidity and Mortality Weekly Report, published by the U.S. Centers for Disease Control and Prevention. The scientists measured the blood pressure of participants, tested blood and urine, and asked what they ate in the last 24 hours. Three to 10 days later, they were again asked what they ate that day. “Statistics presented in the CDC report underscore the urgency of reducing sodium in the U.S. food supply,” the agency said.
About 75 percent of the sodium in the typical American diet is added to commercial foods during processing or during preparation of restaurant foods. Only about 25 percent occurs naturally or is added at the table or in cooking by the consumer, the CDC report explained.
This means that new population-based strategies and increased public health efforts will be required to meet the sodium targets in the 2010 Dietary Guidelines for Americans, the researchers said. “Because usual sodium intake for nearly all U.S. residents exceeds 2010 dietary guidelines, increased efforts involving the public and private sectors -- voluntary reductions in processed and restaurant food - will be needed,” the authors wrote.
“With the direct and indirect costs of cardiovascular disease already at $444 billion a year and rising, and with high blood pressure the single largest driver of those costs, this suggestion doesn’t go far enough to address either the human or economic burden that our excessive intake of salt costs,” said Dr. Gordon Tomaselli of Johns Hopkins University and current president of the American Heart Association. “Other countries have realized this and are addressing it aggressively.”
The researchers note that in the United Kingdom a food manufacturer-government partnership that established voluntary maximum levels of sodium in certain processed foods led to a 9.5 percent reduction in sodium intake over 7 to 8 years. In the United States, a similar reduction in sodium intake would save an estimated $4 billion in health care costs a year and $32.1 billion over the lifetime of adults aged 40 to 85, the researchers said.
The American Heart Association said that the CDC recommendations did not go far enough. “Given that most of us – as many as 90 percent - will develop high blood pressure with age, we all should be consuming less than 1,500 mg a day of sodium, unless your health care provider has told you that this doesn’t apply to you,” Dr. Clyde Yancy, past president of the American Heart Association and the cardiology chief at Northwestern University, said in a statement.