Dr. John Day, Cardiologist

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Restricting Salt May Be Dangerous For Your Heart

Salt is something your doctor has always told you to avoid, right?  In this article, I will share with you the latest medical research showing that, in some cases, restricting salt may be dangerous for your heart.

American Heart Association’s Salt Recommendations

The American Heart Association continues to preach that Americans should reduce their 3,400 mg average of sodium each day to just 1,500 mg.  To put this in perspective, 1,500 mg of sodium is a little more than a half teaspoon of salt.  Is it any wonder that only 1% of Americans can actually follow such strict salt restrictions?

Who wants to eat such a low salt diet?  Our ancestors never ate such bland food. I personally enjoy flavorful food.

Salt Restriction and Heart Failure

Since I started my cardiology training nearly 20 years ago, I was taught that heart failure patients must restrict salt.  When it comes to salt, heart failure patients are like the “canary in the coal mine.”

In other words, if anyone is going to get into trouble from too much salt, it is the heart failure patient.  The thinking was that too much salt led to water retention.  Water retention then caused swollen legs and shortness of breath.

Even today, heart failure patients at my hospital are told to restrict salt.  Are there any medical data to support salt restriction in heart failure?

Salt Restriction Worsens Heart Failure Study

Surprisingly, there are no compelling medical studies supporting the recommendation for heart failure patients to restrict salt.  In fact, a new study showed that salt restriction can actually make heart failure worse.

This past week, cardiologist Dr. Rami Doukky and colleagues from Rush University in Chicago, published a study that has cardiologists around the world questioning everything we have been telling our patients for generations about heart failure.

In this study, Rush University researchers recruited 833 people from 10 different hospitals in the Chicago area.  All patients suffered from severe heart failure.

Some of these heart failure patients restricted their salt to less than 2,500 mg of sodium daily and some did not.  I should point out that the 2,500 mg sodium restriction in this study is far higher than what is allowed with the American Heart Association’s recommended 1,500 mg of sodium each day.

After following these heart failure patients for 36 months, the researchers found that those who restricted salt were 85% more likely to die or be hospitalized during the study!  Wow, the very thing these patients were told to do may have caused them to die prematurely or end up in the hospital.

Of course, I should point out that this was just an observational study.  In other words, just the observation that salt restrictors were more likely to die or be hospitalized doesn’t prove at all that salt restriction was the cause.

There could have been other factors at play to explain these results.  For example, perhaps the salt restrictors were much more sedentary, thus they did not need salt to replace sweat losses from exercising.  That is why my conclusion to this study is that restricting salt may be dangerous for your heart.

Certainly, when it comes to heart failure and salt intake, we need more studies to know what we should be recommending to heart patients.  In the meantime, as long as heart failure patients are not eating a lot of processed and fast foods, they are probably fine flavoring their food with salt unless their doctor tells them otherwise.

Salt and High Blood Pressure

When it comes to salt and high blood pressure, the medical data are pretty clear.  Excessive salt from processed and fast foods raises blood pressure.  Where the medical data aren’t so clear is whether salt, by itself, actually causes heart attacks and strokes.

How much salt should you eat?

This new salt and heart failure study adds further confusion to how much salt you should eat.  This study should not be interpreted that processed and fast food is okay.  Rather, if you rarely eat processed or fast foods then flavoring your “real food” with some salt may be just fine.

To help clarify things, the Institute of Medicine recently reviewed all of the medical studies on salt and came up with the following conclusions:

1. You need at least 1,500 mg of sodium each day to cover sweat losses.

2. Eating up to 2,300 mg of sodium daily is safe.

3. There are not enough quality medical data yet to make any firm salt guidelines.

How do you know how much salt you are eating?

People suffering from high blood pressure should consider tracking their salt intake.  This doesn’t have to be for a long period of time.  Even just a few days would be helpful to at least get an idea of how much salt they are consuming and how sensitive their blood pressure is to salt.  How should this be done?

My Fitness Pal and Lose It are both great free apps to track sodium and nutrition.  Personally, I use the Lose It app.

According to the data compiled by the Health app that comes with all iPhones, I have averaged 1,895 mg of sodium daily for the last year.  This is an underestimation, as I generally don’t take the time to add in the amount of salt I use when cooking or preparing food.  I suspect that if everything was included I would probably end up somewhere near 2,300 mg of sodium or one teaspoon of salt each day.

The Big Picture

Most of the salt in the American diet comes from processed and fast foods.  This is definitely not the way to get salt.  For people who eat minimal processed or fast foods, then you are probably fine flavoring your food with some salt unless your doctor tells you otherwise.

In general, the people who get in trouble from salt are those with high blood pressure on a processed and fast food diet.  For the rest of us, there is no reason to restrict salt unless your doctor has told you to limit salt.

Please leave your comments on this article below.  Also, if you have any questions on this article please leave them below as well and I will answer every question.