Lie — A low-salt diet is good for you

The Story

High blood pressure is bad for your health, possibly fatal.

Sodium in your diet increases blood pressure.

So obviously, a low sodium diet is good for you.



There is a limit to the pressure that our circulatory systems can handle. Excessive pressure can cause aneurysms or aortic ruptures, resulting in stroke or death.

Hypertension is a disease where one's blood pressure is continuously higher than normal. Anyone with hypertension should avoid anything that raises their already high blood pressure as it could push it past their personal limit. For instance, they shouldn't run up stairs, they shouldn't get angry, and they shouldn't eat more salt than they need. Each of these activities increases blood pressure.

Similarly, they should do whatever is reasonable to reduce their normally high blood pressure, giving them a greater margin for survival on those occasions when they do raise their blood pressure temporarily. For instance, walking slowly, remaining calm, and maintaining slightly low levels of sodium by limiting the amount of salt they consume.

For hypertensive people, the benefits of a low-salt diet usually outweigh the risks. But for non-hypertensive people, a low-salt diet offers risks without benefits.


If treating hypertension were as simple as eliminating salt from one's diet, it would be easy. But it isn't. Salt levels that are too low cause hyponatremia, which can interfere with brain processes and cause seizures, comas, and death.

For people with hypertension, a diet needs to be established that balances the benefits and risks associated with blood pressure that's too high and blood sodium that's too low.

Normal people

Most people don't have hypertension. While occasionally consuming large amounts of salt can increase their blood pressure and possibly put them at risk of serious consequences, in most cases the effects are temporary and no harm is done.

When normal people follow advice to reduce their salt intake when they don't need to, they can significantly increase their risk of hyponatremia without necessarily getting any benefit with respect to hypertension.


The real danger occurs when unusual external conditions cause a drop in blood sodium levels. Most people would normally be able to handle this drop, or would know enough to add a little extra salt to their diet.

But people on a low-salt diet, whether on a physician's advice because of actual hypertension or on their own misguided self-help program, get into trouble. They strongly believe that consuming salt will be bad for them, so at such times when it would actually benefit them, they don't.

Whenever the weather produces a long heatwave, people suffer and die needlessly, especially seniors that have faith in their physician's advice. They get hot, they sweat, they lose salt, they drink large quantities of water, and they become dehydrated. All they need do is add some salt or MSG to their glasses of water or lemonade, and they will feel better and stay well (it will taste better too).

But they know salt is evil, so they don't, and they get sick, and they get confused, and they die.


For physicians and dieticians, telling people to avoid salt is a simple rule that most people can understand and follow. Most of the time this is good, or at least harmless, advice. To fully explain the effects of salt and to ensure that patients completely understand the chemical processes involved would require a lot of time and effort. Even if it were fully explained and understood, it would still require that patients use their own judgement, and for many, especially seniors, that judgement isn't as good as it should be.

It's not simply that physicians are lazy and can't be bothered to explain, it's that the risks associated with leaving it up to the patient to decide might very well be worse than the effects of the occasional heat wave.

On the other hand, when there is a heat wave, many physicians don't bother to phone their low-salt patients to let them know that it's okay to have salt today.

And of course for advertisers, putting low sodium or low salt on a product is an easy way to sell more product.


For the vast majority of people, who don't have hypertension, a low-salt diet is unjustifiably dangerous, whatever the weather. Above minimum and occasionally high amounts of dietary salt can be quite beneficial and healthy.

But this article in no way suggests that continually eating excessive amounts of salt is a healthy practice. Consuming too much salt can cause organ damage and death.