August 2011/Prepared Foods -- Little black or white exists, in regards to much nutritional information (to the frustration of consumers). Instead, there is a continuum of plausibility on nutritional information, ranging from “very unlikely to be true” to “pretty darn sure this is the way it is.” I rely on a steady stream of newsletters and websites to keep abreast of emerging nutrition, with the Tufts University Health & Nutrition Letter and Environmental Nutrition being two of my favorites. I have used the Cochrane Reviews on occasion (searchable database at www2.cochrane.org/reviews). The reviews are highly respected and somewhat conservative.

Two Cochrane Reviews have been released on the effectiveness of reducing sodium consumption in improving health. The recent July 2011 review (see http://tinyurl.com/3tst9kn), which was also published in the August 2011 issue of the American Journal of Hypertension, raised a firestorm of comments. Put in simple language, the researchers, headed by Dr. Rod Taylor at the University of Exeter, found insufficient evidence for the long-term health benefits of reducing salt consumption and called for more studies.

The review was countered (blasted may be the better word) by many to most in the healthcare community. Examples include an article in the July 2011 Lancet medical journal (http://tinyurl.com/3fj687j) and a press release by the Center for Disease Control and Prevention (CDC) (http://tinyurl.com/6hbcmw5). 

One can (and many do) argue that the best advice is for the general population to reduce sodium consumption. It is a simple message for consumers to grasp; indeed, segments of our society need serious dietary sodium reductions.

However, that does not mean more research is not needed. Not all people benefit from sodium reductions, and studies exist that even indicate sodium reduction, in some select populations, may be harmful. The Salt Institute lists a number of them (http://tinyurl.com/3row7a6).

One International Food Information Council (IFIC) webpage (http://tinyurl.com/3r2rzr5), under a section titled “Research Gaps on Sodium and Health,” suggests despite the abundance of sodium research, well-designed studies are still needed to address questions such as: How do sodium requirements and their health effects differ between individuals? What are the mechanisms involved in the dietary sodium/blood pressure relationship? What are the practical methods for determining salt sensitivity in humans? Do individuals become salt-sensitive, if exposed to changes in sodium intake for a sufficient period of time? Are there significant effects of dietary sodium, unrelated to blood pressure, on cardiovascular disease (CVD) morbidity and mortality?

Little black and white exists in nutrition, and sodium reduction is making that point one more time. pf