Sodium, Salt, and Science in the age of Dietary Guidance

By: Kris Sollid   Date: 2/4/11

The big day is upon us and the build-up has certainly been "super"-years in the making in fact. The deliberations have ended and now it's time to play ball. Earlier this week the much anticipated policy document, Dietary Guidelines for Americans, 2010 (DGA), was officially unveiled by the US Department of Agriculture (USDA) and Department of Health and Human Services (HHS). Nutrition's Super Bowl has finally arrived; it's time for nutrition professionals to execute the game plan.

Sodium Recommendations
Among the key recommendations outlined in the 2010 DGA is to "reduce daily sodium intake to less than 2,300 milligrams (mg) and further reduce intake to 1,500 mg among persons who are 51 and older and those of any age who are African American or have hypertension, diabetes, or chronic kidney disease." A similar sodium recommendation appeared in 2005, but the 2010 language is slightly more population-specific, adding those with diabetes and chronic kidney disease to the 1,500 mg group and revising the 2005 term "middle-aged and older adults" to read "persons who are 51 and older."

What's in a number?
Dietary recommendations often refer to numbers as targets-consume at least a certain amount of this or keep below a specific amount of that. However, some of these numbers are hard for consumers to digest; take sodium for example. Sodium amounts are typically expressed using the metric system (an international system of measurement). But use of the metric system is limited in the US which can pose a problem for American consumers. So, if you're confused by milligrams, rest assured you're not alone. In terms of sodium, what you should know is that 1 teaspoon of salt contains 2,325 mg of sodium-or about a full days' worth according to the DGA.

How much are we consuming?
Currently, National Health and Nutrition Examination Survey (NHANES) data estimates that the average US daily sodium intake is around 3,400 mg per person-or about one and a half times the 2,300 mg recommendation and more than doubles the 1,500 mg recommendation. According to the IOM Report, Strategies to Reduce Sodium Intake in the US 2010, estimated intake has trended upward when compared to original NHANES data from 1971-1974.

What can the guidelines help us today?
Americans have been trying to reduce sodium intakes since the inaugural DGA stated "avoid too much sodium." Unfortunately, our attempts over the past three decades have been largely ineffective. However, the new guidelines can provide a nice starting point for nutrition professionals to convey sound and effective dietary guidance and help to empower the public to achieve individual sodium intake goals. One such way is by emphasizing healthy eating patterns such as the Dietary Approaches to Stop Hypertension (DASH) and Mediterranean diets. These diets help consumers incorporate more fruits and vegetables (foods that are naturally low in sodium and high in potassium) into their diet while underscoring the importance of low-fat or non-fat dairy, whole grains, lean meats, fish, poultry, nuts, and beans. The DASH diet (plus exercise and weight loss) has been proven to not only reduce blood pressure, but to improve cholesterol, insulin sensitivity, and cardiac functional measures as well.

The 2010 DGA also highlights the importance of flexibility-a point we should not lose sight of. Building flexible and healthy eating patterns that suit our ethnic, cultural, economic, and geographic differences is a critical factor in dietary success as personal preferences will vary among almost every individual. There is no "one size fits all diet", so it's up to nutrition professionals to be patient, sensitive, and work intimately with consumers to ensure they have all the tools necessary to tackle the complex world of food, health, and nutrition. The USDA and HHS have laid out the game plan; it's up to all of us to implement it.