Salt: Back In The Limelight
By Lisa Katic
(Editor’s note: Lisa Katic is a registered dietitian and the Snack Food Association’s public policy adviser for health and nutrition.)
At its annual meeting in June, the American Medical Association recommended that the Food and Drug Administration limit the amount of salt that food companies are allowed to add to products. Specifically, the AMA, which had never before called for regulation of a food ingredient, asked the FDA to: revoke salt’s long-time status as a substance that is “generally recognized as safe,” a classification that warrants little oversight regulate salt as a food additive
If adopted, packaged food companies would have to adhere to limits on allowable sodium levels for various categories of food and accelerate the search for an alternative preservative and flavor enhancer.
In February of 2005, the Center for Science in the Public Interest (CSPI) released a report entitled, “Salt: the Forgotten Killer,” which claims that salt intake contributes to tens of thousands of premature deaths each year. At the time of the report’s release, CSPI also filed suit against the FDA and asked the U.S. Court of Appeals in the District of Columbia to require that the FDA increase its regulatory authority to lower sodium levels in processed foods.
Both of these initiatives have thrust salt into the limelight as a public health concern and raised questions about how attentive the FDA has been regarding the issues of excess sodium consumption. In response, the FDA said that within the next few months it will solicit comments in preparation for a hearing or workshop on the health concerns about salt, something the agency has never done. However, to date there has been no scheduled workshop publicly announced.
The food industry, which opposes any additional regulation of salt, is lobbying the government to stop attempts to force companies to limit salt in food. In August 2006, the Salt Institute, which represents companies such as Morton International and a $340 million salt market, met with the Department of Health and Human Services to lobby against additional salt regulation by the FDA. Food companies say they are working voluntarily to lower the amount of sodium in their products and have done so over decades by creating reduced-, low- and no-sodium products, as well as making changes that the consumer never sees. Despite such efforts, American sodium consumption has not declined in recent years.
So, what is all the fuss? First a little primer on the origins of salt.
Since ancient times, salt has been used for numerous purposes beyond that of flavoring food. It is probably one of the most widely used of all food ingredients. Salt was used as a major trading commodity in several ancient civilizations and was even traded ounce-for-ounce for gold. In some parts of the world, coins were made of salt and salt cakes were used as money.
Salt permeated historic culture to the extent that several present-day quotes draw upon the history of salt for their meaning; for example, the ancient Greeks were known for exchanging salt for slaves, which gave rise to the expression “not worth his salt,” and the Romans gave salt rations to their soldiers, which were known as “salarium agentum,” the precursor to the word “salary.”
Salt as a food ingredient
Salt is primarily used in food to enhance flavor. On average, the salt found naturally in food accounts for only about 10% of total intake in the diet, while salt added at the table or in cooking provides about another 5-10% of total intake. The rest is derived from sodium added to foods during processing by manufacturers. Scientists have tried for decades to mimic the taste of salt in foods by developing salt substitutes, but have had limited success.
Salt can serve as a peripheral taste function in food, and by adding just a few grains to a food, it can bring out the natural flavor without contributing an overly salty taste. Surprisingly, foods with higher sodium levels do not necessarily taste salty. And the reverse also is true. Foods with salt on the surface, such as French fries or potato chips, have a greater salty taste but do not typically contain more sodium than, say, baked goods or even some cereals where the sodium is incorporated into the food.
Salt also is used to balance out any chemical aftertastes in products such as soft drinks and is added to bread dough to enhance and even out the texture.
Salt’s role in maintaining health
Sodium or salt is contained in all fluids in the human body, including blood, sweat and tears. Its primary role in the body is to regulate blood volume and pressure, which is why sodium intake from foods is said to have a direct impact on blood pressure. Some researchers have pointed out that even significant reductions in sodium intakes have lead to very small reductions in blood pressure in the population.
A couple of points to consider in the debate over sodium and hypertension:
Research has shown that any response in blood pressure due to a decrease in sodium is generally minimal and fleeting.
A subset of the population that is “salt-sensitive” tends to benefit the most by reducing dietary salt intake and, at the same time, altering other dietary deficiencies such as potassium and calcium. (Salt-sensitivity is usually defined as a measure of how blood pressure responds to a decrease in salt intake. Those with the greatest decrease in blood pressure as a result of decreased salt intake are identified as salt-sensitive.) Presently, there is no standardized definition of salt sensitivity.
The bottom line
It is known that sodium plays an important role in food processing and maintaining health. Most people in the United States and around the world consume more sodium in their diets than is recommended by health professionals. Ongoing discussions about dietary sodium have led to a better understanding of the relationship between sodium and blood pressure and the thought that lowering sodium in the diet is beneficial for many people. What still is unknown is the exact level of sodium intake needed to improve blood pressure and whether it is useful for the entire population to lower sodium intake when the results are so mixed.
Finding a method to identify salt-sensitive individuals and studying the effects of salt on their blood pressure will go a long way in offering a more precise recommendation for sodium intake in the diet.
Although there have been repeated calls over the last 25 years to re-address salt’s GRAS status, the FDA’s office of food additive safety calls the prospect of rescinding its “safe’’ status difficult because it would require writing regulations for a “very complex issue.”
The debate on sodium has been active for decades and will continue to be as long as the science on sodium is so inconclusive and shows varied results in the population. It is unlikely that FDA will make great changes to the way sodium in the food supply is currently regulated. However, if companies are able to incrementally decrease the sodium in their products without drastically changing the taste and characteristics of the food, a little goes a long way.