Salt is bad for blood pressure but good for brain development, researchers say.
Pass the salt: Who hears that anymore? Salt's been nearly banished, and rightly so. Too much salt affects blood pressure -- and not in a good way. But for some people, cutting back has a downside.
Take stock of the facts.
Too little salt -- iodized salt, that is -- is dangerous, too. It's the iodine in iodized salt that helps the body make thyroid hormone, which is critical to an infant's brain development.
A little salt is essential to good health. Healthy adults should consume salt and water to replace the amount lost daily through sweat and to achieve a diet that provides sufficient amounts of other essential nutrients.
The American Heart Association and NIH advise adults to get no more than 2,400 milligrams of sodium daily. That's about 1 teaspoon of salt. Just think how salty your favorite snacks taste. Eat too many salty foods (even soft drinks have sodium), and you easily go overboard.
Truth About Iodized Salt
Is the salt in your kitchen salt iodized? Most people don't know. "Most people buy just whatever one their hand grabs... and until about five years ago, it didn't really matter," says Glen Maberly, MBBS, MD, an endocrinologist and professor of international health in the Rollins School of Public Health at Emory University School of Medicine in Atlanta.
Yet getting too little iodine -- called iodine deficiency -- is a serious issue. Iodine is an essential mineral for the production of thyroid hormones. Too little iodine in a pregnant women's diet can affect the development of the fetus' brain and can cause cretinism, an irreversible form of physical and mental retardation. Iodine deficiency during infancy can also result in abnormal brain development and impaired intellectual development.
"The developing brain is the most sensitive organ. Iodine deficiency doesn't make people idiots, but it does make them less smart," says Maberly.
In the U.S., iodine deficiency is more common in women than men. It's also common in pregnant women and adolescents, he tells WebMD.
Iodine deficiency is thought to be rare in the U.S. It's considered a problem of third-world countries, but Maberly disagrees. "Iodine nutrition in the U.S. is borderline," he tells WebMD. "A pregnant woman may not be protected. Even if she eats a normal diet, her intake is probably inadequate. Only 70% of table salt is iodine-fortified."