To Protect Your Heart, Your Sodium to Potassium Ratio Is More Important Than Your Overall Salt Intake
Dr. Mercola
The vilification of salt is similar to that of fat. Just as there are healthy fats that are necessary for optimal health and unhealthy fats that cause health problems, there are healthy and unhealthy types of salt. The devil’s in the details, as they say, and this is definitely true when it comes to salt and fat.
Salt provides two elements – sodium and chloride – both of which are essential for life. Your body cannot make these elements on its own, so you must get them from your diet. However, not all salts are created equal.
Besides the basic differences in nutritional content, the processing—which involves drying the salt above 1,200 degrees Fahrenheit—also radically and detrimentally alters the chemical structure of the salt
- Natural unprocessed salt, such as sea salt and Himalayan salt, contains about 84 percent sodium chloride (just under 37 percent of which is pure sodium1, 2). The remaining 16 percent are naturally-occurring trace minerals, including silicon, phosphorus, and vanadium
- Processed (table) salt contains 97.5 percent sodium chloride (just over 39 percent of which is sodium3, 4). The rest is man-made chemicals, such as moisture absorbents and flow agents, such as ferrocyanide and aluminosilicate.
Appropriate vs. Inappropriate Salt Restriction
In the United States and many other developed countries, salt has been vilified as a primary cause of high blood pressure and heart disease. According to research presented at last year’s American Heart Association meeting,5 excessive salt consumption contributed to 2.3 million heart-related deaths worldwide in 2010.
However, it’s important to realize that most Americans and other Westerners get the majority of their sodium from commercially available table salt and processed foods—not from natural unprocessed salt.
This is likely to have a significant bearing on the health value of salt, just as dangerous trans fats in processed foods turned out to be responsible for the adverse health effects previously (and wrongfully) blamed on healthy saturated fats.
Current dietary guidelines in the US recommend limiting your salt intake to anywhere from 1.5 to 2.4 grams of sodium per day, depending on which organization you ask. The American Heart Association suggests a 1.5 gram limit.
For a frame of reference, one teaspoon of regular table salt contains about 2.3 grams of sodium.6 According to some estimates, Americans get roughly four grams of sodium per day, which has long been thought to be too much for heart health.
But recent research, which has been widely publicized,7, 8, 9, 10, 11 suggests that too little salt in your diet may be just as hazardous as too much. Moreover, the balance between sodium and potassium may be a deciding factor in whether your salt consumption will ultimately be harmful or helpful.
Too Little Salt Raises Heart Risks Too, Researchers Find
One four-year long observational study (the Prospective Urban Rural Epidemiology (PURE) study), which included more than 100,000 people in 17 countries, found that while higher sodium levels correlate with an increased risk for high blood pressure, potassium helps offset sodium’s adverse effects.
The results were published in two articles: "Association of Urinary Sodium and Potassium Excretion with Blood Pressure"12 and "Urinary Sodium and Potassium Excretion, Mortality, and Cardiovascular Events."13
I’ve discussed the importance of getting these two nutrients—sodium and potassium—in the appropriate ratios before, and I’ll review it again in just a moment.
In this study, those with the lowest risk for heart problems or death from any cause were consuming three to six grams of sodium a day—far more than US daily recommended limits.
Not only did more than six grams of sodium a day raise the risk for heart disease, so did levels lower than three grams per day. In short, while there is a relationship between sodium and blood pressure, it’s not a linear relationship.14 As noted by the Associated Press:15
"‘These are now the best data available,’ Dr. Brian Strom said of the new study. Strom, the chancellor of Rutgers Biomedical and Health Sciences, led an Institute of Medicine panel last year that found little evidence to support very low sodium levels.
"‘Too-high sodium is bad. Too low also may be bad, and sodium isn't the whole story,’ Strom said. ‘People should go for moderation.’
The authors propose an alternative approach; instead of recommending aggressive sodium reduction across the board, it might be wiser to recommend high-quality diets rich in potassium instead. This, they surmise, might achieve greater public health benefits, including blood-pressure reduction.
As noted by one of the researchers, Dr. Martin O'Donnell16 of McMaster University, “Potatoes, bananas, avocados, leafy greens, nuts, apricots, salmon, and mushrooms are high in potassium, and it's easier for people to add things to their diet than to take away something like salt.”
Meta-Analysis Supports Lower Sodium Recommendations
Another study,17 published in the same journal, assessed how sodium contributes to heart-related deaths by evaluating 107 randomized trials across 66 countries. The researchers first calculated the impact of sodium on high blood pressure, and then calculated the relationship between high blood pressure and cardiovascular deaths. According to the authors:
“In 2010, the estimated mean level of global sodium consumption was 3.95 grams per day, and regional mean levels ranged from 2.18 to 5.51 grams per day. Globally, 1.65 million annual deaths from cardiovascular causes... were attributed to sodium intake above the reference level [2.0 grams of sodium per day]. These deaths accounted for nearly 1 of every 10 deaths from cardiovascular causes. Four of every 5 deaths occurred in low- and middle-income countries, and 2 of every 5 deaths were premature (before 70 years of age).”
This appears to support current sodium recommendations in the US, and according to Dr. Elliott Antman, president of the Heart Association,18 “The totality of the evidence strongly supports limiting sodium.” However, as noted by Dr. Suzanne Oparil, M.D.:19 “[G]iven the numerous assumptions necessitated by the lack of high-quality data, caution should be taken in interpreting the findings of the study. Taken together, these three articles highlight the need to collect high-quality evidence on both the risks and benefits of low-sodium diets.”
Earlier Evidence
A long list of studies has in fact failed to prove that there are any benefits to a low-salt diet, and in fact many tend to show the opposite. In addition to the ones already mentioned above, the following studies also came up with negative results. For an even more comprehensive list of research, please see this previous salt article.
"Intensive interventions, unsuited to primary care or population prevention programs, provide only minimal reductions in blood pressure during long-term trials."
Of particular note is the authors statement that: “sodium reduction resulted in a significant increase in plasma cholesterol (2.5 percent) and plasma triglyceride (7 percent), which expressed in percentage, was numerically larger than the decrease in BP [blood pressure]... The present meta-analysis indicates that the adverse effect on lipids, especially triglyceride, is not just an acute effect as previously assumed, but may be persistent also in longer-term studies.”
- A 2004 meta-analysis by the Cochrane Collaboration20 reviewed 11 salt-reduction trials and found that, in otherwise healthy people, over the long-term, low-salt diets decreased systolic blood pressure by 1.1 millimeters of mercury (mmHg) and diastolic blood pressure by 0.6 mmHg. That equates to reducing your blood pressure from 120/80 to 119/79. In conclusion, the authors stated that:
- A 2006 study in the American Journal of Medicine21 compared the reported daily sodium intakes of 78 million Americans to their risk of dying from heart disease over the course of 14 years. The study concluded that 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."
- In 2011, the Cochrane Collaboration22, 23 conducted yet another review of the available data, concluding that when you reduce your salt intake, you actually increase several other risk factors that could theoretically eliminate the reduced risk for cardiovascular disease predicted from lowering your blood pressure!
You Need Salt, But Make Sure It’s the Right Kind
From my perspective, the answer is clear: avoid processed salt and use natural salt in moderation. I believe it is hard for a healthy person to overdo it if using a natural salt, as salt is actually a nutritional goldmine—again provided you mind your sodium-potassium ratio. Some of the many biological processes for which natural salt is crucial include:
Being a major component of your blood plasma, lymphatic fluid, extracellular fluid, and even amniotic fluid Carrying nutrients into and out of your cells, and helping maintain your acid-base balance Increasing the glial cells in your brain, which are responsible for creative thinking and long-term planning. Both sodium and chloride are also necessary for the firing of neurons Maintain and regulate blood pressure Helping your brain communicate with your muscles, so that you can move on demand via sodium-potassium ion exchange Supporting the function of you adrenal glands, which produce dozens of vital hormones The beauty with Himalayan salt is that in addition to being naturally lower in sodium, it’s much higher in potassium compared to other salt—including other natural salt like sea salt or Celtic salt. Himalayan salt contains 0.28 percent potassium, compared to 0.16 percent in Celtic salt, and 0.09 percent in regular table salt. While this may seem like tiny amounts, Himalayan salt still has a better salt-potassium ratio than other salt, especially table salt. Again, remember that besides the basic differences in nutritional content, it’s the processing that makes table salt (and the salt used in processed foods) so detrimental to your health. What your body needs is natural, unprocessed salt, without added chemicals.
The Importance of Maintaining Optimal Sodium-Potassium Ratio
I agree with the PURE study’s authors when they say that a better strategy to promote public health would be to forgo the strict sodium reduction element, and focus recommendations instead on a high-quality diet rich in potassium, as this nutrient helps offset the hypertensive effects of sodium. Imbalance in this ratio can not only lead to hypertension (high blood pressure) but also contribute to a number of other diseases, including:
Heart disease and stroke Memory decline Osteoporosis Ulcers and stomach cancer Kidney stones Cataracts Erectile dysfunction Rheumatoid arthritis The easiest way to throw your sodium-potassium ratio off kilter is by consuming a diet of processed foods, which are notoriously low in potassium while high in sodium. (Processed foods are also loaded with fructose, which is clearly associated with increased heart disease risk, as well as virtually all chronic diseases.) Your body needs potassium to maintain proper pH levels in your body fluids, and it also plays an integral role in regulating your blood pressure. As indicated in the PURE study, potassium deficiency may be more responsible for hypertension than excess sodium. Potassium deficiency leads to electrolyte imbalance, and can result in a condition called hypokalemia. Symptoms include:
- Water retention
- Raised blood pressure and hypertension
- Heart irregularities/arrhythmias
- Muscular weakness and muscle cramps
- Continual thirst and constipation
According to a 1985 article in The New England Journal of Medicine, titled "Paleolithic Nutrition,24” our ancient ancestors got about 11,000 milligram (mg) of potassium a day, and about 700 mg of sodium. This equates to nearly 16 times more potassium than sodium. Compare that to the Standard American Diet where daily potassium consumption averages about 2,500 mg (the RDA is 4,700 mg/day), along with 3,600 mg of sodium. This may also explain why high-sodium diets appear to affect some people but not others.
According to a 2011 federal study into sodium and potassium intake, those at greatest risk of cardiovascular disease were those who got a combination of too much sodium along with too little potassium. The research, published in the Archives of Internal Medicine,25 was one of the first and largest American studies to evaluate the relationship of salt, potassium, and heart disease deaths. Tellingly, those who ate a lot of salt and very little potassium were more than twice as likely to die from a heart attack as those who ate about equal amounts of both nutrients.
How to Optimize Your Sodium-to-Potassium Ratio
To easily determine your sodium to potassium ratio every day, you can use a free app like My Fitness Pal for your desktop, smartphone, or tablet that will easily allow you to enter the foods you eat and painlessly make this calculation for you. No calculating or looking up in multiple tables required like we had to do in the old days. So, how do you ensure you get these two important nutrients in more appropriate ratios?
- First, ditch all processed foods, which are very high in processed salt and low in potassium and other essential nutrients
- Eat a diet of whole, unprocessed foods, ideally organically and locally-grown to ensure optimal nutrient content. This type of diet will naturally provide much larger amounts of potassium in relation to sodium
- When using added salt, use a natural salt. I believe Himalayan salt may be the most ideal, as it contains lower sodium and higher potassium levels compared to other salts
I do not recommend taking potassium supplements to correct a sodium-potassium imbalance. Instead, it is best to simply alter your diet and incorporate more potassium-rich whole foods. Green vegetable juicing is an excellent way to ensure you’re getting enough nutrients for optimal health, including about 300-400 mg of potassium per cup. By removing the fiber you can consume even larger volumes of important naturally occurring potassium. Some additional rich sources in potassium are:
- Lima beans (955 mg/cup)
- Winter squash (896 mg/cup)
- Cooked spinach (839 mg/cup)
- Avocado (500 mg per medium)
Other potassium-rich fruits and vegetables include:
- Fruits: papayas, prunes, cantaloupe, and bananas. (But be careful of bananas as they are high in sugar and have half the potassium that an equivalent of amount of green vegetables. It is an old wives’ tale that you are getting loads of potassium from bananas; the potassium is twice as high in green vegetables)
- Vegetables: broccoli, Brussels sprouts, avocados, asparagus, and pumpkin
How Much Salt Does Your Body Need?
Normally, the homeostasis of your body fluids is corrected primarily by your kidneys, and proper renal handling of sodium is necessary for normal cardiovascular function. Given that your survival and normal physical development are dependent on adequate sodium intake and retention, the question is – how much salt do you really need?
A strictly vegetarian diet contains about 0.75 grams of salt per day, and it’s been estimated that the Paleolithic diet contained about 1 to 1.5 grams, which was clearly sufficient for survival, even though it falls far below the currently recommended amount.
I believe it’s clear that most Americans consume FAR too much processed salt that is devoid of most any health benefit. But if you want to find out whether you’re eating the right amount of salt for your body, a fasting chemistry profile that shows your serum sodium level can give you the answer, so that you can modify your diet accordingly. As a general rule, your ideal sodium level is 139, with an optimal range of 136 to 142. If it is much lower, you probably need to eat more salt (natural and unprocessed varieties, of course); if it is higher, you’ll likely want to restrict your salt intake. Keep in mind that if you have weak adrenals, you will lose sodium and need to eat more natural salt to compensate.