Why Low-Salt Diets Are Dangerous During Pregnancy

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Salt is absolutely essential to health. It is one of the five basic tastes we have receptors for in our mouth (along with sweetness, bitterness, sourness and umami), and it is an important element in the body’s “interior ocean”.

The human body tightly regulates salt concentration because it is crucial to chemical reactions that support enzyme function, energy and hormone production, protein transport and several other biological processes.

In the context of pregnancy, salt is critical for the development of the glial (immune) cells in the brain. It also plays an important role in ensuring adequate birth weight, metabolic function and development of the nervous, respiratory and cardiovascular system.

Salt is especially important to the brain development of premature babies. In premature babies, language, memory, intelligence and coordination were all better in children whose diets had been supplemented with salt shortly after birth.

A low-salt diet is dangerous for pregnant women

A 2007 study found that babies with low sodium in their blood (due to low salt intakes by their mothers during pregnancy) were more likely to be underweight at birth. Low birth weight is associated with a higher risk of developing several health problems later in life.

Another study found that infants with low sodium intake may experience poor neurological function in early adolescence.

The false accusations against salt

Salt has been unjustifiably demonized by the mainstream media and medical establishment. As recently as January 2010, so-called health authorities have been clamoring for a national program to reduce dietary salt intake to “prevent tens of thousands of heart attacks, strokes and deaths and trim as much as $24 billion from the U.S. health care tab”.

To support this spurious claim, they reference a computer simulation which suggested the impact of salt reduction would be similar to prevention strategies like quitting smoking or losing weight.

Computer simulations are interesting and fun for programmers to make, but what do actual studies that look at real human beings eating salt tell us?

They tell us that it has never been proven that salt significantly increases the risk of cardiovascular disease, hypertension or obesity. In fact, in many cases restricting salt intake can actually increase the risk of these conditions. For example, a review of the largest U.S. database of nutrition and health (NHANES) found a higher rate of cardiac events and death with patients on low-salt diets.

Visit this page for a list of studies clearly demonstrating that dietary salt intake prevents – rather than causes – disease. For a comprehensive article covering all of the issues related to salt intake, click here.

Chris Kresser
Chris Kresser is the founder of the Kresser Institute and a health detective specializing in investigative medicine. He is a blogger, podcaster, teacher, and Paleo diet and lifestyle enthusiast.

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