— Shannon Dolph, Portland, Oregon
A: Given all the warnings about sodium raising blood pressure, you might think the link between the two is crystal clear. Actually, it's still a bit out of focus. One reason for the lack of clarity is that salt sends some people's blood pressure soaring while others seem able to tolerate heaps of it, no harm done. This inconsistent response has led to the notion of salt sensitivity, a trait generally thought to occur in at least 10 percent of the population. So far there's no easy way to test for salt sensitivity—or its absence (though researchers seem to be narrowing in on a "salt gene"). And since several studies suggest that most people benefit to varying degrees from minding their sodium intake, public health officials keep things simple by recommending that everyone cut back on salt. Besides, high blood pressure isn't the only concern: Even when blood pressure remains normal, high-sodium diets have been linked to heart disease (the theory is that excess sodium can directly damage the arteries and heart). And high-salt diets may rob your bones of calcium, potentially weakening bones and leading to osteoporosis.
But you may not need to worry if you eat a healthy diet and prepare most of your own meals: Five percent of the sodium in the average American's diet is added during cooking, 6 percent comes from the shaker on the table, another 12 percent occurs naturally in food, and the remaining 77 percent comes courtesy of processed, prepackaged foods . Cook your meals using fresh, whole ingredients and you'll get only a quarter of the 4,000 milligrams of sodium the typical American consumes in a day. That would put you well under the recommended daily limit of 2,300 milligrams.
One last note: Sodium can turn up in surprising places. That big, healthy-looking bran muffin on the coffee-shop counter can pack nearly 800 milligrams. Some breakfast cereals deliver up to 600 milligrams a bowl. Highly processed, sweetened foods may conceal a great deal of sodium and not taste salty at all.
What about sea salt?
David L. Katz, MD, is director of the Yale-Griffin Prevention Research Center and president of the nonprofit Turn the Tide Foundation.