Warning: prepare for whiplash! We know that for the last 50 years you have heard a constant drum beat from public health officials, cardiologists, nutritionists and most other health professionals that a low salt diet is a healthy diet. Almost everyone has been told to cut sodium intake.
The American Heart Association (AHA) has remained adamant that salt is the enemy:
“The American Heart Association recommends no more than 2,300 milligrams (mg) a day and an ideal limit of no more than 1,500 mg per day for most adults, especially for those with high blood pressure.”
Almost half of all American adults have high blood pressure! That’s based on AHA guidelines. The American Heart Association wants more than 120 million people to cut salt intake dramatically. In practical terms that means:
- No salted nuts
- No chips, pretzels, pizza, pickles or olives
- No packaged shrimp, canned clams or tuna or frozen crab legs
- No canned or packaged soup unless it specifically says low-salt
- No bagels, bread or buns unless marked low-sodium
- No cold cuts
We could go on and on, but you get the idea.
It is hard to wrap your head around a different message, so please brace yourself.
What Are the Risks of a Low Salt Diet?
In a the journal, JAMA Internal Medicine (January, 2014), an important article was published titled:
The Institute of Medicine Report Sodium Intake in Populations: Assessment of Evidence Summary of Primary Findings and Implications for Clinicians
What is the “Institute of Medicine”?
Why should anyone pay attention to findings from the Institute of Medicine (IOM)? This organization has been around since 1970. It was founded under the umbrella of the National Academy of Sciences (NAS). What, you may ask, is the NAS? It dates back to 1863 when President Abraham Lincoln and Congress created an organization to provide advice about science and technology.
The IOM focuses on healthcare and is an independent, nonprofit non-governmental organization. It has been renamed the National Academy of Medicine (NAM). The people who serve on the NAM are among the best and the brightest in American medicine. They are chosen for outstanding contributions in medicine by their peers.
A Personal Note:
The president of the National Academy of Medicine is Victor Dzau, MD. We got to know and work with Dr. Dzau when he was President and CEO of the Duke University Health System. Terry and I served on both the Patient Advocacy Council and the Patient Safety and Clinical Quality Committee of the Duke University Health System under Dr. Dzau. We had many opportunities to work with him on important patient safety issues and came to admire his vision and leadership.
We provide this background to reinforce the point that the IOM study on salt has a great deal of gravitas.
What Did the Study Find?
In the scientists’ own words, here are the findings of the IOM report:
“For patients with diabetes mellitus, hypertension, chronic kidney disease, or preexisting cardiovascular disease, the committee found no evidence of benefit and the suggestion of harm at sodium intake of 1500 to 2300mg/d. The committee concluded that these subgroups should not be treated differently from the general US population and that the literature did not support recommendations to lower sodium intake within these subgroups to 1500 mg/d or less.
“For patients with congestive heart failure, the committee found evidence for potential harm associated with sodium consumption below 2300 mg/d.
“The IOM committee’s conclusions have 2 important implications for practice. First, the lack of evidence of benefit and concerns for harm suggest that low sodium intake (<2300 mg/d) should not be recommended. This finding has particular implications for high-risk subpopulations (including those with heart failure) for whom many guidelines had recommended targets as low as or lower than 1500 mg/d. Second, the evidence of cardiovascular benefit (both from studies of direct cardiovascular effects and from trials on blood pressure) does support a decrease in sodium consumption for most Americans because most are consuming considerably more than 2300 mg/d.”
These IOM conclusions are at odds with the American Heart Association. Scroll up to the start of this article and you will see that the AHA is still advocating that most Americans get their sodium intake below 1,500 mg per day. The AHA is adamant about very low sodium intake, “especially for those with high blood pressure.” Many physicians still encourage their patients with heart failure to cut salt dramatically.
Did the Prior Experts Get Their Advice About a Low Salt Diet Wrong?
High-risk patients have been told for decades that they must lower their salt intake dramatically to be healthy. The IOM REPORT is saying that the advice to follow a low salt diet might have been wrong.
Although they do suggest that a high-sodium diet is common in the U.S. and that we should try to moderate our salt intake, they also urge caution about the guidelines set by public health organizations to get sodium intake below 1500 mg daily.
Okay, that’s just the first article that challenges standard wisdom and policy. Here’s a knock-out punch. The November 2013 issue of The American Journal of Medicine has a review article titled: “Dietary Sodium Restriction: Take It with a Grain of Salt.”
Strap on your seatbelt. These experts have reviewed the research on sodium and they are even more outspoken than the Institute of Medicine. They contradict the American Heart Association’s goal to achieve “Ideal Cardiovascular Health” by lowering dietary sodium to 1500 mg per day. Here are some selected quotes:
Low Sodium Intake and Blood Pressure:
“Although there are reasonable data to support that sodium restriction lowers blood pressure, the effects may be transient and inconsistent, with some individuals even having paradoxical increases in blood pressure [emphasis mine]. The degree of blood pressure lowering on average might be clinically trivial, approximately 2 mm Hg in normotensive individuals and approximately 4 mm Hg in hypertensive individuals. Finally, sodium restriction also has the adverse effects of activating the renin-angiotensin-aldosterone system, increasing catecholamines, and adversely affecting insulin and lipids.”
What that means in plain English is that restricting sodium does not make a meaningful difference in blood pressure reduction and may lead to a stressful physiological reaction. Adrenaline (epinephrine) goes up along with insulin (not a good thing). Increases in lipid levels mean that your cholesterol levels could climb (also not a good thing).
But wait, it gets even more confusing. Here again are selected quotes from The American Journal of Medicine article about “Dietary Sodium Restriction: Take It with a Grain of Salt”:
Low Sodium Intake and Type 2 Diabetes:
These reviewers point out that people with type 2 diabetes who cut way back on salt may have a higher death rate from cardiovascular causes compared to diabetics who consume a normal level of salt. Even more heretical was their analysis of the data on heart failure:
Low Sodium Intake and Systolic Heart Failure:
“The low sodium diet caused increased mortality and heart failure hospitalizations versus normal sodium diet in patients with systolic heart failure. These results have been verified across multiple randomized, controlled trials in patients with systolic heart failure.”
Low Sodium Intake and Thyroid Function:
“A major source of dietary iodine is through salt. Therefore, a low sodium diet could lead to worsening of thyroid diseases.”
And for the grand finale, their summary:
There is no conclusive evidence that a low sodium diet reduces cardiovascular events in normotensive and pre-hypertensive or hypertensive individuals. On the contrary, there is sound evidence that a low sodium diet leads to a worse cardiovascular prognosis in patients with systolic congestive heart failure or type 2 diabetes mellitus. Worldwide sodium restriction, through its adverse effects on insulin resistance, may lead to an increase in the rates of type 2 diabetes mellitus…Advising low sodium diets seems misguided and potentially dangerous and illustrates the problem of guidelines based on flawed studies using surrogate measures.”
Wow and WOW! What are we to make of this turn-around? For starters, your health professional has probably not read the IOM report or this article in The American Journal of Medicine. The American Heart Association is still aiming for less than 1,500 mg of sodium a day. Here is what the premier public health organization (the Centers for Disease Control and Prevention” stated on its website:
…”If you are in the following population groups, you should consume no more than 1,500 mg of sodium per day…
- You are 51 years of age or older
- You are African American
- You have high blood pressure
- You have diabetes
- You have chronic kidney disease
The 1,500 mg recommendation applies to about half of the U.S. population overall and the majority of adults. Nearly everyone benefits from reduced sodium consumption.”
The Dangers of a Low Salt Diet for Some People:
Up until now you have been reading stuffy scientific reports. For many people, such blah, blah is boring. Let’s get real for a moment.
A few years ago, we heard from a reader who had been avoiding salt conscientiously for years:
“One day my sodium level dropped to 125 and I started jerking and was near convulsions. After an ambulance ride to the emergency room, I learned how important it is to watch your salt intake. I was told by the hospital doctor to drink less water so as not to lose too much sodium through my urine.
“The ER doctor also told me to eat extra table salt. When my sodium finally reached 134, which is only one point lower than the normal range, I started feeling so much better.”
The ER physician was addressing the emergency of that moment with advice to drink less water. Drinking too little water in hot weather is also dangerous, as it can lead to dehydration. However, getting too much plain water without enough sodium can result in hyponatremia (low sodium), as our reader discovered. Other electrolytes such as potassium and magnesium are also important.
Some Medications Make a Low Salt Diet More Dangerous:
We would be the first to admit that many people consume way too much salt. For them, moderation makes sense!
But we worry about blanket advice to cut salt intake as much as possible. Although some people are salt sensitive and will see a drop in blood pressure when they get less sodium in their food, others do not react so strongly. Some even develop high blood pressure when they cut salt drastically. Moreover, people with high blood pressure—precisely those urged to avoid salt—often take medicine to control hypertension.
Diuretics and a Low Salt Diet:
Diuretics are frequently the drugs of choice, but thiazide diuretics such as hydrochlorothiazide or furosemide (Lasix) can deplete the body of many minerals, including sodium as well as magnesium and potassium.
SSRIs and PPIs and a Low Salt Diet:
Other medications that may create an imbalance in minerals include antiepileptics, SSRI antidepressants and even proton pump inhibitors such as esomeprazole (Nexium), lansoprazole (Prevacid) or omeprazole (Prilosec). Some people taking such drugs have experienced hyponatremia (American Journal of Kidney Diseases, July 2008). It is prudent for patients to have their electrolyte balance monitored regularly, especially during hot weather.
Some other people are actually being advised to increase their salt and fluid intake. In the aftermath of COVID-19, many individuals now suffer from long COVID. One of the possible complications of this condition is POTS (postural orthostatic tachycardia syndrome).
Those with this mysterious health challenge experience dizziness when standing up quickly. This can sometimes lead to fainting, which can be very dangerous. Other symptoms include rapid heart rate, brain fog, exhaustion and anxiety.
There aren’t many treatments that can relieve POTS. However, some doctors recommend increased salt and fluid intake along with medications that can help control heart rate.
Salt is not our enemy. Without sodium, our bodies do not function. As a result, we endorse the old adage of moderation in all things, including salt.
A number of commonly prescribed medications can affect your electrolyte balance. People who are prescribed diuretics like hydrochlorothiazide (HCT or HCTZ) are often monitored for potassium levels. That is a good thing. They should also be monitored for minerals like magnesium, sodium and zinc. You can read about case reports of hyponatremia and HCTZ at this link.
Now that proton pump inhibitors are available without a prescription, we suspect that most people assume they are completely safe. We have written extensively about the potential adverse reactions associated with PPIs. They too can deplete the body of certain minerals such as calcium, iron, magnesium and sodium.
If you would like to read more about the dangers of salt restriction for heart failure, pease check out our article on this controversial topic at this link.
How do you cope with these completely contradictory messages? We have to wonder whether our public health officials are even bothering to read the medical literature. What do you think? Please share your experience and your thoughts on this complicated and confusing issue below.
If you think this article would benefit friends or family members, please share it via email or social media. You can do that by scrolling to the top of the article and clicking on one of the icons. Thank you for your support. We remain your independent voice for patient safety.