Column #110

Salt is an essential nutrient your body requires and also self-regulates. Hyponatremia, a low sodium condition, is associated with an increased risk of death. So why is the medical community so afraid of salt?

James J. DiNicolantonio, who recommends against low-salt diets, wrote The Salt Fix. He is a cardiovascular research scientist, doctor of pharmacy at Saint Luke’s Mid America Heart Institute in Kansas City, Missouri, and the associate editor of British Medical Journal’s (BMJ) Open Heart. He has authored and/or coauthored 200 publications in medical literature.

Salt sensitivity varies significantly with equal numbers being very sensitive, mildly sensitive, and insensitive. It seems to correlate with overall health. This is why people with hypertension should take tests to clarify their sodium response.

Generally, salt intake has a greater adverse impact on health and blood pressure of people with elevated blood sugar levels. Therefore anyone with metabolic syndrome (pre-diabetes) and diabetes should be more cautious of salt intake. For those with congestive heart failure, limiting salt intake can make a positive difference because extra sodium can cause fluid overload that a weak heart can’t tolerate. Salt intake also modestly impacts bone density because more salt causes calcium to pass out of the kidneys into the urine. On the other hand, it’s highly questionable for healthy people with normal blood pressure (less than 120/80) and normal bone density to worry about salt.

The war on salt started around 1900. Interestingly, the low salt diet was paired with a diet consisting of 7.0 ounces of rice, 10.5 ounces of wheat flour, 17.6 ounces of potato, 3.5 ounces of white cheese, 3.5 ounces of sugar, and one quart of water. This diet allowed fairly high amounts of sugar because in those days sugar was considered harmless.

The early studies reporting salt restriction benefits were not randomized controlled trials but simply case reports, mainly on hospitalized patients who by merely being hospitalized could have created a blood pressure lowering “benefit.” In 1929 another study using a pretreatment control period showed that “no consistent effect on the blood pressure was observed when high salt intakes were instituted.”

Then in the early 1940s Dr. Walter Kempner began publishing reports about his low-salt, rice diet which stimulated enthusiasm for the low-salt treatment of hypertension which is still widely followed today in spite of the fact his data did not support his conclusions. In fact, additional independent studies have shown that low-salt diets are dangerous.

Controlling hypertension is important for better heart health. Yet for over 100 years dietary approaches mainly focused on sodium reduction’s debatable benefits. Instead, what may be giving the low-salt approach more credence is that most of the sodium in the diet comes from processed foods that are also high in added sugar and sugar is strongly associated with hypertension and cardiometabolic risk.

Dr. DiNicolantonio says that, “Evidence from epidemiological studies and experimental trials in animals and humans suggests that added sugars, particularly fructose, may increase blood pressure and blood pressure variability, increase heart rate and myocardial oxygen demand, and contribute to inflammation, insulin resistance and broader metabolic dysfunction.”

The argument now is that sodium is minimally tied to blood pressure and perhaps even inversely related to cardiovascular risk while the problem lies with sugar and carbohydrates.

In his paper, The wrong white crystals: not salt but sugar as aetiological in hypertension and cardiometabolic disease, Dr. DiNicolantonio makes the point that added sugars probably matter more than dietary sodium for hypertension. Fructose is a uniquely high cardiovascular risk. It causes metabolic dysfunction and increases blood pressure variability, the heart’s oxygen demand, heart rate, and inflammation. Instead of focusing on limiting dietary sodium, reducing consumption of added sugars and carbohydrates is the best place to start.

To your health.

Ted Slanker

Ted Slanker has been reporting on the fundamentals of nutritional research in publications, television and radio appearances, and at conferences since 1999. He condenses complex studies into the basics required for health and well-being. His eBook, The Real Diet of Man, is available online.

Don’t miss these links for additional reading:

The Salt Fix at Amazon.com

The History of Salt Wars by James J. DiNicolantonio, PharmD, James H. O’Keefe, MD

The Wrong White Crystals: Not Salt but Sugar as Aetiological in Hypertension and Cardiometabolic Disease by James J DiNicolantonio and Sean C Lucan

British Medical Journal’s (BMJ) Open Heart

How Do You Cope with Changing Recommendations? By The People's Pharmacy

Hyponatremia from Wikipedia

Dr. Walter Kempner’s Rice Diet from Wikipedia

Human Salt Requirements