Salt and sodium. What`s the difference?
Until recently there wasn`t much, as far as heart patients and most nutritionists were concerned. The standard advice was to avoid all forms of sodium, including sodium chloride, the chemical name for table salt.
The reason? American diets, typically sky-high in sodium, were thought to be a major contributor to our national epidemic of high blood pressure.
But that long-held belief was questioned recently when researchers at the University of California at San Francisco announced results of a study that seemed to single out table salt as the culprit, taking the blame off other forms of sodium. Their study showed that table salt had a pronounced effect in raising the blood pressures of five men they tested, yet other forms of sodium had little or no effect.
But a leader of the research team said that it is premature to single out table salt or exonerate other forms of sodium.
``I don`t believe our article provides the basis for making dietary recommendations,`` said Dr. Curtis Morris, director of the university`s General Clinical Research Center.
``We studied only five men with hypertension, and the results we found are entirely consistent with previous research,`` Morris said.
Another scientist who is prominent in sodium research agrees.
``This does not mean we only need to worry about the salt shaker,`` said Dr. Michael Zemel, associate professor of nutrition and food science and of endocrinology and hypertension at Wayne State University in Detroit.
Much of the ordinary salt in our diets is found in processed and fast foods, Zemel said, so eliminating salt that is added at the table is not enough to help blood-pressure patients: ``It`s the rare processed food that has only a nonchloride sodium salt.``
Other medical conditions, involving fluid imbalances, are equally affected by all forms of sodium; so those patients must continue to watch all forms of the chemical.
Finally, not all forms of sodium have been evaluated, Zemel said. The California researchers compared table salt, or sodium chloride, to sodium citrate, an additive in many foods and beverages.
Other forms of sodium in our diets include:
- Monosodium glutamate, a flavor enhancer often found in processed and Oriental foods.
- Sodium benzoate, a preservative.
- Sodium bicarbonate, or baking soda, found in baked goods and cereals.
- Sodium ascorbate, a form of Vitamin C, often used as a preservative.
- Sodium nitrite, a preservative found in bacon and other processed meats, usually in small amounts.
Reducing salt is no cure-all for hypertension (high blood pressure), Zemel said. Only those patients with a salt sensitivity will have their blood pressure improved by reducing salt intake.
Blacks and elderly people are most likely to be salt-sensitive, although countless Americans have varying degrees of sensitivity, Zemel said.
He added: ``I think a moderate decrease in our sodium intake would be good for all of us. To the extent that you reduce your dependence on prepared and processed foods, that`s great. But if you start worrying about every bit of sodium in foods, you may be denying yourself some important nutrients. For instance, I think it`s foolish to eliminate dairy products from your diet just because they have a bit of sodium.``