Table salt has been demonized when it comes to blood pressure. Public health campaigns urge people to reduce their salt intake, and doctors ask about it at office visits. The message seems to have taken hold; a report in this week’s MMWR (Morbidity and Mortality Weekly Report, the CDC’s weekly update on diseases) says that about half of adults are either watching their salt intake or taking steps to reduce it.
The bad reputation is undeserved, though. Table salt is perfectly fine for you, when used moderately. In fact, your body needs salt to function properly. Some studies show that too little can worsen problems with both cholesterol and insulin.
So why all the buzz? Breathless news headlines in 2013 proclaimed that 10% of all deaths in the US can be linked to our excessive salt consumption. Groups from the World Health Organization to the American Heart Association recommend cutting our national salt intake by half or more.
The Real Culprit in High Blood Pressure
There’s no question we consume lots of salt. The guilty party, though, appears to be the sodium in salt. On average, Americans consume about 3.6 grams of sodium daily, which is just a little less than the world average of 4 grams daily. If we got all that sodium from table salt, it would come to nearly 2 teaspoons. There’s more sodium in our diets than just table salt, though.
Practically every processed food out there contains sodium in one form or another. Sodas and fruit juices contain sodium benzoate, used as a preservative. Processed meats contain sodium nitrate, also as a preservative.
The most widely used sodium source is MSG, or monosodium glutamate, found in everything from ketchup to ice cream. It’s bad enough that MSG is such a prevalent source of sodium. In addition, though, MSG has been linked to a seemingly endless list of health problems. Nearly 20 years ago a special editorial supplement in the Journal of Nutrition listed all the known reactions to MSG, including burning sensations, difficulty breathing, chest pain, and changes in heart rate.
(As a side note, there’s lots of noise on the web and elsewhere about how MSG “hides” under names such as textured vegetable protein, autolyzed yeast, and hydrolyzed protein, which can cause the same health reactions as MSG. In fact, these reactions are due to the other part of MSG, glutamic acid, which is formed during processing of the protein. If you’re sensitive to MSG, then certainly do watch out for these ingredients, but they won’t have any effect on your sodium intake.)
When you look at statistics on individuals, it appears that those who consume more sodium are at greater risk of high blood pressure. And it’s clear that higher blood pressure increases your risk for all sorts of health conditions. But a 2013 report by the Institute of Medicine reviewed 38 clinical studies on the effect of sodium consumption on overall health. They found that sodium intake had no effect on the ultimate outcome (death), and in fact for several groups the current dietary guidelines were actually harmful.
Some people are sodium-sensitive—but it’s less than a third of us. (The rate of sodium sensitivity is significantly higher among African-Americans.) If you are one of the few who are sodium-sensitive, it does make sense to watch how much salt you consume. The biggest culprit is prepared food, especially restaurant food. Some meals contain more than 5 grams of salt. (Check the restaurant’s menu online to get nutritional information.) And while one of these meals every now and then won’t give you high blood pressure, if you’re one of the many folks who eat out more than once a week or so then all the extra salt can add up.