06/28/2010 05:12 am ET Updated Nov 17, 2011

Salt: Who's the Boss of You?

On April 20, the Washington Post reported that the FDA is planning to dial down the salt content in processed foods over a 10 year span by regulating the maximum levels allowed. It turns out this isn't quite right. The FDA has been encouraged to do just this in a report on the subject by the Institute of Medicine, but hasn't actually decided yet. In the end, though, the FDA is likely to follow the IOM's advice -- and if so, it will be a good idea, with one important caveat.

First, it's a good idea because an excess of sodium is linked to high blood pressure and consequently to stroke, the fourth leading cause of death and a major cause of disability in the US. Estimates vary, but some persuasively contend that excess sodium is the indirect cause of 150,000 premature deaths a year.

Second, it's a good idea because overwhelmingly, our salt intake is courtesy of processed foods which have salt engineered into them -- not from our own salt shaker. Nearly 80 percent of the salt in a typical American diet is put there by manufacturers, not by us.

Third, it's a good idea because that salt is not necessarily where you expect it. Many popular breakfast cereals are more concentrated in sodium than you want your diet to be on average. If your breakfast cereal pulls your average salt intake up above guidelines, what the heck is going to pull it down?

Fourth, it's a good idea because we all too readily acclimate to high levels of salt. Our love affair with dietary salt is of an ancient lineage. In fact, it should probably be traced back to the very first creatures that dragged themselves out of the briny shallows onto dry land. Going terrestrial meant giving up a constant supply of sodium, and suddenly made the mineral a prized commodity. Deer will come to a salt lick with good reason -- sodium in nature is hard to find for creatures not swimming in it.

And that's true of us, too. The native, Stone Age human diet provided roughly 10 times as much potassium as sodium (we actually get more sodium than potassium in the typical, modern diet). Yet, sodium is essential. So those of our ancestors who craved it, and thus were motivated to get enough of it, did a better job of passing on their genes. After all, those who don't survive to pass on genes make for very poor ancestors.

Those of us around today inherited genes from salt-loving forefathers and foremothers. But in a world of limited sodium, their salt-cravings fostered their survival and procreation; in a world of French fries, Cheerios, and Bugles, our inherited salt craving fosters hypertension, stroke and osteoporosis.

We sanctified our fondness of salt in our lexicon. The town of Salzburg, Austria was established as a commerce center dealing in salt. Its name means, in essence, 'Salt Village.' The word 'salary' means salt in Latin. Roman legionaries were actually 'paid' with the prized and precious mineral.

Fifth, it's a good idea because taste buds are very malleable little fellas: when they can't be with the foods they love, they learn to love the foods they're with. Familiarity is one of the more potent drivers of dietary preference.

The food industry case is that they are simply providing us the salt levels we prefer, and to some extent this is true. But we have learned to prefer such copious additions of salt to our diets because our taste buds are bathing in sodium excess all day long, and have habituated.

It works just as well in the other direction: if the feds help dial down our exposure to sodium, we will get more sensitive to sodium, and prefer less. My taste buds are beneficiaries of a very pure, 'practice of what I preach' diet. As a consequence, I simply can't eat most commercial breakfast cereals, because they taste way too salty to me. I suppose I could have them with beer, but not with milk!

I noted at the start that there is one caveat tempering my support for FDA's move. That comes from my work in measuring the overall nutritional quality of foods. All too often, in scoring foods with the NuVal system, we have seen scores for overall nutritional quality DECLINE in foods that are salt reduced, or for that matter, sugar or fat reduced. That's because such reformulations typically boast about the one 'good' change, but are mum about a host of compensatory, undesirable changes: salt comes out, but sugar goes in; sugar comes out, but salt and fat go in; sugar comes out, but so does fiber -- and so on.

We really cannot improve nutritional quality, diets, or health, one nutrient at a time. It is overall nutritional quality that matters. I do not want sodium to be the dietary scapegoat du jour that causes us to lose sight of all the other nutritional properties that matter.

Assuming we can dial down our salt exposure while maintaining or improving overall nutritional quality, FDA's efforts in this area promise to rehabilitate our taste buds and protect our health. As a contribution to efforts that take us to that place where we can still love food, but it loves us back -- I support it.

I can, however, imagine one vociferous protest to my position, and that of the IOM: isn't this just one more example of 'Big Brother' telling us what to do? The answer comes down to your preferences for salt, siblings and shelf life.

You see, salt content in processed foods has gone up for a number of reasons. Some research shows that the human appetite center is activated by combining multiple flavors at a time; I suspect that is at least part of the reason sweet cereals and desserts contain as much sodium as they do. Bet you can't eat just one!

Your preference for salt levels that are irrefutably at odds with your health, and the health of your children- is a by-product of native traits and tendencies from the Stone Age, clashing with modern food industry practices. I doubt you 'want' salty breakfast cereal, or cookies (yes, those too!)- but the industry is giving them to you, and manipulating your taste buds in the process. So, you are currently being bossed around, not by Pennsylvania Avenue, but by Madison Avenue. Is that really better?

In addition, and more obviously, salt extends shelf life. The longer foods go without spoiling, the less waste there is for the food company, and the higher the profits. But here's the rub: by and large, the longer the shelf life of the foods people eat, the shorter the shelf life of the people eating the foods. So, it seems, the government would like to prioritize the shelf life of people over products, and arguably, any resistant elements in the food industry would rather go the other way. You can decide which of these platforms you prefer in an older sibling, but I've made my choice, and it seems a no-brainer to me!

Since it is much easier to add salt to food than to take it out after someone else has added it, it seems to me the regulation under consideration puts more control where the salt shaker is -- in your hands. No 'sibling' has expressed any desire to take that shaker away. You can always add salt whenever you want. I doubt it will be when you are eating cookies, but you're the boss. Isn't that how it should be?


Dr. David L. Katz,