By Dr. Mercola
The idea that salt is bad for you and contributes to heart disease is an idea that has become more or less cemented as dogma in the West. Where did this idea come from? And more importantly, is it true?
My intention today is to show you the fallacy of the notion that salt is generally bad for you, and how salt has been indicted by so-called nutritional "experts," as well as by government regulators, without a fair trial. When you look at what the research actually says, I believe you will be convinced that salt is not only relatively benign but is a major nutritional goldmine, IF you consume the right kind.
You have probably had the benefits of a low-salt diet drummed into your head for years.
However, decades of scientific research have failed to prove ANY benefits of a low-salt diet, and in fact tend to show the opposite. Studies have also failed to prove salt's connection to heart disease. I will show you where this mistaken idea originated… and the sound you hear may be cardiologists' hearts breaking across the globe.
Salt is an Essential Nutrient
Salt is essential for life—you cannot live without it. Salt has always been important to human life on this planet. Even the word "salary" comes from the root "sal," because Romans were paid in salt. African and European explorers traded an ounce of salt for an ounce of gold—salt was literally worth its weight in gold. Unrefined natural salt is important to many biological processes, including:
- Being a major component of your blood plasma, lymphatic fluid, extracellular fluid, and even amniotic fluid
- Carrying nutrients into and out of your cells
- Maintain and regulate blood pressure
- Increasing the glial cells in your brain, which are responsible for creative thinking and long-term planning.
- Helping your brain communicate with your muscles, so that you can move on demand via sodium-potassium ion exchange
More than 80 percent of the salt most people consume is from processed foods. Indeed, there is far too much sodium in processed foods. But you shouldn't be eating those foods anyway—sodium is just one of MANY ingredients in packaged foods that will adversely affect your health. The salt added to these convenience foods is mostly sodium—as opposed to natural salt, which is much lower in sodium. I'll be discussing more of the differences between natural and refined salt shortly.
DASH-ing the Sodium Myth: Salt as the Scapegoat for Sugar
If you repeat something long enough, people will believe it's true. And this seems to be the case with salt. The genesis of the sodium myth lies with one study that seemed to show a link between salt and hypertension.
Yes, just ONE study.
In 1997, the DASH-sodium study was conducted to determine whether or not a low-salt diet would control hypertension. The DASH diet consists largely of fresh vegetables and fruits, lean protein, whole grains, and low-fat dairy, and is very low in salt. But it's ALSO low in sugar/fructose. So, while people on DASH diets do show reduced hypertension, the reason for this is not the reduction in salt, but the reduction in fructose.
Hypertension is actually promoted more by excess fructose than excess salt.
Researchers were so eager and personally invested in proving their salt theory that they completely overlooked other factors, thereby drawing the wrong conclusion altogether. This is where the sodium myth really gained its footing. Salt got the blame for the damage sugar was causing in a monumental rush to judgment.
The amount of salt Americans eat pales in comparison to the amount of fructose they consume on a daily basis, and I'm convinced that sugar/fructose—rather than salt—is the major driving force behind our skyrocketing hypertension rates. Gary Taubes is an investigative science and health journalist and author of several books, including Good Calories, Bad Calories.
In his classic 1988 article "The (Political) Science of Salt," Taubes wrote:
"While the government has been denouncing salt as a health hazard for decades, no amount of scientific effort has been able to dispense with the suspicions that it is not. Indeed, the controversy over the benefits, if any, of salt reduction now constitutes one of the longest running, most vitriolic, and surreal disputes in all of medicine….
The data supporting universal salt reduction have never been compelling, nor has it ever been demonstrated that such a program would not have unforeseen negative side effects… After decades of intensive research, the apparent benefits of avoiding salt have only diminished. This suggests either that the true benefit has now been revealed and is indeed small, or that it is nonexistent, and researchers believing they have detected such benefits have been deluded by the confounding influences of other variables…"
Blood pressure drops as much in low-sugar studies as it did in the DASH-sodium study, but this fact has been conveniently ignored. Even though researchers have repeatedly failed to prove the salt/heart disease link, agencies like the National Institutes of Health (NIH) and the U. S. Department of Agriculture (USDA) climbed aboard the anti-salt train, and salt has been painted as "Public Enemy Number One" ever since.
One reason could be because it directed attention away from the real culprit behind high blood pressure and heart disease—specifically, excess sugar and grain carbohydrates. Whether or not that culprit is known by these agencies is up for debate, but by restricting salt, at least they maintain the appearance that they're doing something to address the increasing cardiovascular disease epidemic. Once the notion of salt's evilness became lodged in the mind of the public, very few bothered to check the facts, and this medical myth became accepted as truth.
The Link Between Fructose and Cardiovascular Disease
Let's review how excess dietary sugar and refined carbohydrates can set you up for developing cardiovascular disease. Hypertension is the common thread linking obesity, type 2 diabetes, gout, heart disease and stroke. But there is ANOTHER common denominator among those diseases: insulin resistance. And what do we know causes insulin resistance? Sugar and refined carbohydrates—primarily fructose.
Sugar and refined carbohydrates raise your insulin levels, which in turn raise your blood pressure and promote storage of body fat, obesity, diabetes and heart disease. The reason fructose does this more than any other sugar is that your body produces uric acid as a byproduct of fructose metabolism, and increased uric acid levels drive up blood pressure. No one explains this more clearly than Dr. Richard Johnson, and I recommend you listen to my interview with him if you want to really understand this basic physiological phenomenon.
What the science shows is very clear. It isn't the salt doing this—it's the fructose. The preponderance of evidence shows that sodium intake does NOT affect blood pressure unless you are especially sodium-sensitive. But there is an added problem with salt-restricted diets.
Can Your Sodium Ever be TOO Low?
Yes it can!
You may not be aware of this, but your risk for health problems increases significantly if your sodium is too low, a condition known as hyponatremia. Sodium is an electrolyte responsible for many critical biological processes, including regulating the amount of water that's in and around your cells, so if your blood becomes too low in sodium, your body's fluid levels rise and your cells begin to swell. This swelling can cause a number of health problems, from mild to severe.
According to the Mayo Clinic:
"A low-sodium, high-water diet can sometimes disturb the proper balance between sodium and fluids in your blood."
Other causes of hyponatremia include medications, drinking too much water during exercise, dehydration, and certain diseases, including those affecting the function of your liver, kidneys, and thyroid gland. At its worst, hyponatremia can be life threatening, leading to brain swelling, coma and death. Premenopausal women appear have the highest risk of hyponatremia-related brain damage due to how female hormones affect women's ability to regulate sodium levels. But mild to moderate hyponatremia has more subtle effects that you or your healthcare provider may not even connect with an electrolyte problem. Hyponatremia can present with the following signs and symptoms:
|Nausea, vomiting, and changes in appetite
|Loss of energy
||Nervousness, restlessness and irritability, and other mood changes
|Muscle weakness, spasms or cramps
Changes in mood and appetite are among the first noticeable manifestations of sodium deficiency, yet the cause is often missed. Yet, in order to stave off heart disease, the advice you are likely receiving is, "drink lots of water, exercise vigorously, and cut back on your salt." Talk about a setup for electrolyte disaster! There is evidence that low sodium levels can damage your health in other ways. Consider the following scientific studies:
- A 2009 study of large-bone fractures in the elderly found the incidence of hyponatremia in patients with fractures was MORE THAN DOUBLE that of non-fracture patients. They postulated the reason for the sodium deficiency might have been the use of selective serotonin receptor inhibitors (SSRIs), a type of antidepressant drugs.
- A 1995 study by the AMA, published in the journal Hypertension, found low urinary sodium associated with an increased risk of heart attack.
Twenty-Five Years of Scientific Evidence Fails to Show Any Benefit of a Low-Salt Diet
To help you access relevant research, I have assembled a chronological list of the main research studies about low-salt diets from the past three decades. As you will see from the table that follows, the benefits of low-salt diets have been quite "underwhelming" in the scientific literature.
|J Chronic Dis 1987: The number of people who experience drops in blood pressure after eating high-salt diets almost equals the number who experience blood pressure spikes; many stay exactly the same.
|Intersalt study, BMJ 1988: Conclusion: There is no relationship between sodium and hypertension; in fact, those who ate the most salt had a LOWER median blood pressure than those who ate the least salt.
|DASH-sodium study, NEJM 1997: Conclusion: "A diet rich in fruits, vegetables, and low-fat dairy foods and with reduced saturated and total fat can substantially lower blood pressure. This diet offers an additional nutritional approach to preventing and treating hypertension." (Related Mercola article: Higher Salt Intake Tied to Longevity)
|NHANES I, Lancet 1998: Conclusion: "These results do not support current recommendations for routine reduction of sodium consumption, nor do they justify advice to increase salt intake or to decrease its concentration in the diet." (Related Mercola article: Take the Latest Low Sodium Advice With a Grain of Salt)
|Cochrane review 2003: Conclusion: "There is little evidence for long-term benefit from reducing salt intake."
|NHANES II, Am J Med 2006: Conclusion: Lower sodium diets led to HIGHER mortality rates among those with cardiovascular disease, which "raised questions regarding the likelihood of a survival advantage accompanying a lower sodium diet."
|Rotterdam Study, Eur J Epidemiol 2007: Conclusion: "From this and other epidemiological studies we conclude th effect of dietary salt on clinical cardiovascular endpoints and overall mortality within the range of intake commonly observed in Western countries has not yet been established."
|Clin Sci (Lond) 2008: Low-sodium diets result in WORSE clinical outcomes for people with congestive heart failure, due to "detrimental kidney and neurohormonal effects."
|Cochrane review 2011: Conclusion: Cutting down on the amount of salt has no clear benefits in terms of likelihood of dying or experiencing cardiovascular disease.
|Rotterdam Study, JBMR 2011: Conclusion: "Mild hyponatremia in the elderly is associated with an increased risk of vertebral fractures and incident nonvertebral fractures, but not with bone mineral density. Increased fracture risk in hyponatremia also was independent of recent falls, pointing toward a possible effect on bone quality."
|JAMA 2011: Conclusion: "Systolic blood pressure, but not diastolic pressure, changes over time aligned with change in sodium excretion, but this association did NOT translate into a higher risk of hypertension or cardiovascular disease complications. Lower sodium excretion was associated with higher cardiovascular disease mortality."
|Meta-Analysis AJH 2011: Conclusion: "Despite collating more event data than previous systematic reviews, there is still insufficient power to exclude clinically important effects of reduced dietary salt on mortality or cardiovascular disease morbidity."
The second to last study in the table above deserves some explanation. This recent study followed 3,681 middle-aged healthy Europeans for eight years. The participants were divided into three groups: low salt, moderate salt, and high salt consumption. Researchers tracked mortality rates for the three groups, with the following results:
- Low-salt group: 50 people died
- Moderate salt group: 24 people died
- High-salt group: 10 people died
In fact, the risk for heart disease was 56 percent higher for the low-salt group than for the group who at the most salt. So the only reasonable conclusion the researchers could make was, the less salt you eat, the more likely you will die from heart disease. This absolutely flies in the face of conventional views.
In an article in Newswise, Dian Griesel, Ph.D., co-author of the book TurboCharged: Accelerate Your Fat Burning Metabolism, Get Lean Fast and Leave Diet and Exercise Rules in the Dust, explains:
"The optimal level of salt in our diets has been a controversial subject for at least 20 years. There is no disagreement that high blood pressure (even moderately high) is a risk factor for heart disease and stroke. However, salt consumption does not seem to have the same effect on everyone. In addition, there is usually no distinction on the type of salt used."
He is absolutely right. All forms of salt are not equal.
Type of Salt Matters
Today's table salt has practically nothing in common with natural salt. One is health damaging, and the other is healing. Natural salt is 84 percent sodium chloride, and processed salt is 98 percent. So, what comprises the rest?
The remaining 16 percent of natural salt consists of other naturally occurring minerals, including trace minerals like silicon, phosphorous and vanadium. But the remaining two percent of processed salt is comprised of man-made chemicals, such as moisture absorbents, and a little added iodine.
You might be tempted to think "salt is salt," but even the structure of processed salt has been radically altered in the refining process. Refined salt is dried above 1,200 degrees Fahrenheit, and this excessive heat alone alters the natural chemical structure of the salt. What remains after ordinary table salt is chemically "cleaned" is sodium chloride,
The processed salt is not pure sodium chloride but is only 97.5 percent sodium chloride and anticaking and flow agents are added to compromise about 2.5 percent. These are dangerous chemicals like ferrocyanide and aluminosilicate. Some European countries, where water fluoridation is not practiced, also add fluoride to table salt. In France, 35 percent of table salt sold contains either sodium fluoride or potassium fluoride and use of fluoridated salt is widespread in South America.
Salt as Nature Intended it: Himalayan Crystal Salt
The more you can move toward a diet of whole organic foods in their natural state, the healthier you'll be—whether it's veggies, meat, dairy products, or salt.
Given that salt is absolutely essential to good health, I recommend switching to a pure, unrefined salt. My favorite is an ancient, all-natural sea salt from the Himalayas.
Himalayan salt is very special. It is completely pure, having spent many thousands of years maturing under extreme tectonic pressure, far away from impurities, so it isn't polluted with the heavy metals and industrial toxins of today. And it's hand-mined, hand-washed, and minimally processed. Himalayan salt is only 85 percent sodium chloride, the remaining 15 percent contains 84 trace minerals from our prehistoric seas. These trace minerals are important for, among other things, good bone health, as explained by Dr. Robert Thompson in his book The Calcium Lie.
It's also the most delicious salt you'll ever find—so much so that I always caution people before they use it because once most people taste it, they have a very difficult time ever using conventional salt again. That is one of the reasons why so many gourmet chefs exclusively use this salt.
So, please, relax and salt your food to taste, provided the salt you're using is natural and unrefined. If you are exercising heavily, or in the middle of a heat wave, you may require more salt than on a cool day when you're relaxing. And remember, the more processed foods you consume, the higher your sodium will be, as it is hidden is just about everything that comes in a box or can. And of course, this is NOT the kind of salt your body needs.
So there you have it, the sodium myth debunked.
To learn even more about this and other health myths, sign up for the 2011 Weston A. Price conference, which will take place in Dallas, Texas, from November 11 to November 13. The conference will feature a long list of prominent health experts, including yours truly.
To sign up, please see the Weston A. Price conference page.