Salt is an essential nutrient for our health, yet health authorities often urge us to reduce our intake over blood pressure concerns.
But did you know that too little salt can be just as damaging as too much?
In fact, some people even believe that an insufficient salt intake is more dangerous than a high consumption.
After reading ‘The Salt Fix‘, the new book by Dr. James DiNicolantonio, I thought this would be a good topic to delve into.
Notably, this intriguing book argues that salt has unfairly taken the blame for the adverse effects of some very different white crystals; sugar.
So, should we follow conventional advice to consume no more than a teaspoon per day?
Or is it better to be wary of sodium deficiency?
This article takes an in-depth look at salt, the benefits, drawbacks, and some of the views in the aforementioned book.
What is the Difference Between Salt and Sodium?
First of all, people use the words salt and sodium almost interchangeably.
Is salt the same thing as sodium? Not quite.
Salt is a naturally occurring mineral with a crystal-like appearance, and it contains two elements; sodium (Na) and chlorine (Cl).
These two elements occur at a ratio of approximately 40% sodium to 60% chlorine (1).
As a result, the chemical name for salt is sodium chloride (NaCl), and it is essential not only for humans but all animal life (2).
There are also many different kinds of salt we can buy.
Some of the more popular options include crystalline salts such as Himalayan pink salt, Fleur de sel and sea salt. There is also common table salt, which has the appearance of a fine white powder.
Salt has been part of the human diet for thousands of years. Over the years, it has been vital for preserving food – especially before the advent of refrigeration.
Salt’s excellent preservation and moisture-controlling properties are the reason we can find it in a vast variety of foods.
Some of the most popular foods which contain large amounts of salt are bacon, sauerkraut, cheese, and kimchi.
Sodium is one of the two electrolyte minerals contained within salt. Along with chlorine, it plays a critical role in a range of biological processes.
The Benefits of Salt
Quite literally, if sodium in our body falls too low (hyponatremia), then we may slip into a coma and possibly die (3).
Here are some functions of sodium in the body;
- Blood pressure regulation: the joint action of sodium and potassium control the water volume of every cell. Therefore, they also contribute to blood pressure (4).
- Optimal muscular and nerve function: In conjunction with other electrolytes, sodium helps the nerves send electrical signals telling the muscles to contract (5).
- Maintains an optimal electrolyte balance in the body: Sodium is one of the minerals necessary for a proper electrolyte balance in the body (6).
- Supports a healthy metabolism: Iodine is critical for our thyroid health, so the intake of iodized salt can be very beneficial (7, 8)
- Improves blood sugar control: One thing many people don’t know about salt is that a sufficient amount increases insulin sensitivity. Likewise, very low salt intakes can lead to a sodium deficiency and insulin resistance (9, 10).
- Helps maintain stomach PH: Consuming a low salt diet may result in insufficient secretion of hydrochloric acid (11).
Salt and Blood Pressure Regulation
Sodium determines the volume of fluid in our cells, and thus plays an important role in regulating blood pressure.
Despite claims that too much salt causes high blood pressure, it is not quite so simple.
In fact, a recent study utilizing a 16-year follow-up period found that participants consuming less than 2,500 milligrams (about 6g salt) of sodium each day had higher blood pressure on average than those consuming higher amounts (12).
Interestingly, this figure is very close to the ‘maximum’ salt intake of 2,300mg recommended by the dietary guidelines (13).
However, studies show a long-term “high” intake of salt may lead to excessive levels of sodium in the blood, which can raise blood pressure (14).
The big question is: how much is too much and is that amount the same for every individual?
Furthermore, studies show only a “weak relationship” between high blood pressure and salt in the general population. Only some people exhibit large changes in blood pressure in response to salt, which is known as “salt sensitivity” (15).
In other words, we need salt, and it’s good for us, but there’s a delicate balance between sufficient and too much salt.
Salt Intake by Country
Here are the twenty countries with the highest salt consumption (15);
The first thing that stands out here is that these nations are predominantly Asian.
This makes sense because Asian cooking tends to use the most seasoning in the world.
Given we always hear too much salt raises blood pressure, surely these countries will have the highest blood pressure rates.
But is that the case?
Highest Blood Pressure by Country
According to the World Health Organization (WHO), the twenty countries having the highest rate of individuals with raised blood pressure are (16);
|Rank||Country||Raised Blood Pressure %|
|9||The Czech Republic||34.4|
|12||Bosnia and Herzegovina||34.0|
|14||Republic of Moldova||33.6|
|19||Republic of Macedonia||32.7|
Notably, you may notice that not one of the countries with the highest salt intake is in the top twenty.
Additionally, the countries with the highest prevalence of raised blood pressure are predominantly Eastern European.
So, what do the blood pressure rates look like for the nations with the highest salt intake?
Raised Blood Pressure Rates For the Nations Consuming the Most Salt
|Country||Salt Per Day (g)||Raised BP %|
As you can see in this table, the rate of high blood pressure doesn’t correspond to the salt intake.
Notably, the four Eastern Asian countries—China, Japan, Korea and Singapore—show a much lower rate of high blood pressure.
It’s worth noting that these four countries mainly consume salt from fermented foods and salty broths. Would these foods have a different effect compared to unhealthy processed foods loaded with salt?
Perhaps salt consumption isn’t the issue and the foods that contain the salt are?
Studies on High Salt Intake
Cardiovascular Disease and Stroke
High blood pressure is the biggest risk factor for cardiovascular disease and stroke (17).
Some studies show that reducing our salt consumption lowers blood pressure.
Two meta-analyses agree, with one claiming that salt restriction “significantly reduces” blood pressure.
As mentioned earlier, there is also a study from April 2017 that followed participants for 16 years and found that those consuming the least salt had the highest blood pressure (12).
In other words, there doesn’t appear to be any conclusive consensus.
A wealth of epidemiological studies links high salt diets to stomach cancer.
- A 2012 meta-analysis of pre-existing studies found that dietary salt has a direct association with the risk of gastric cancer, “with the risk progressively increasing across consumption levels” (20).
- However, several Japanese observational studies find a positive link between the sodium excretion rate and stomach cancer incidence, but dietary salt intake alone had no association (21, 22, 23).
- Animal studies using mice and rats show that salt intake alone doesn’t have a significant effect on increasing carcinogenesis. However, when combined with carcinogens (such as H. Pylori – a stomach bacteria), there was a significant increase in tumors (24, 25, 26, 27).
- In contrast, some studies show that high salt intake is a risk for stomach cancer regardless of possible confounders (28, 29, 30).
Although the studies do suggest an overall positive association between excessive salt and stomach cancer, the studies are very mixed.
Sadly, none of these studies control for quality of diet.
For example, most of the salt people are eating comes from “ultra-processed food” which represents 57.9% of the American diet (31).
A pretty big confounder.
Sodium Deficiency Destroys Health: The Perils of Low Salt Intake
Despite the potential dangers of a very high salt intake, that does not mean we should unnecessarily restrict salt.
Dr. James DiNicolantonio and several other prominent researchers caution that low salt intake is more damaging than a high consumption.
Different levels of salt have both benefits and risks, but we shouldn’t underestimate the importance of salt in our diet.
Here are some of the dangers of low salt levels and sodium deficiency;
Sodium Deficiency and Heart Health
- In 232 patients suffering from congestive heart failure (CHF), a study compared low sodium and “normal” sodium diets. Over a 180 day follow-up period, 12.71% of the “normal sodium” group were readmitted due to worsening CHF or died. In contrast, there was a 39.47% readmission or mortality rate in the ‘low sodium’ patents (32).
- Some studies show that those with a lower sodium intake have a higher rate of death from cardiovascular disease. Other studies indicate that both a very high and a very low sodium intake increases mortality (34, 35).
- A low sodium diet decreases blood pressure by only 1% in healthy people and 3.5% in hypertensive patients. However, this diet also results in a 7% increase in triglycerides and has been shown to damage the arteries and induce atherosclerosis in mice – despite a lower blood pressure (36, 37).
- A review of the existing literature finds there is “no conclusive evidence that a low sodium diet reduces cardiovascular events.” Conversely, there is also solid evidence that “low sodium diets lead to a worse CVD prognosis in patients with heart failure or type 2 diabetes” (38).
Type 2 Diabetes
- Despite guidelines to reduce salt intake, lower sodium consumption is associated with an increase in all-cause and cardiovascular deaths in diabetics (39).
- A growing amount of research shows that low salt diets—and sodium deficiency in particular—increase insulin resistance. In a randomized controlled trial, modest salt restriction over five days decreased insulin sensitivity by 15% (40, 41, 42).
How Much Salt Do I Need?
As with many things in the nutrition world, there is no uniform perfect amount of salt for every individual.
In truth, the optimal sodium intake per day will differ from person to person and depends on various lifestyle factors like activity level and current health.
As mentioned previously, the recommended salt intake is “a maximum of” 2,300mg sodium per day (about 6 grams salt). As of right now, the studies on salt are mixed. Overall, signs of harm from both excessive salt and sodium deficiency exist.
The best bet is likely somewhere in between. Dr. James DiNicolantonio puts the ideal amount of salt somewhere between 8 and 10 grams per day.
Additionally, the Japanese are one of the healthiest nations in the world. The fact that their high salt intake is predominantly from soups and ferments rather than processed food probably isn’t a coincidence.
Personally, I don’t really keep track of the amount of salt I’m eating and salt my food to a level which tastes good.
The Salt Fix
The information on the harms of sodium deficiency in this article is only a drop in the ocean compared to the scope of ‘The Salt Fix’ book by Dr. DiNicolantonio.
If you are looking for more information on this topic, then this book would be a great tool.
It features over 250 pages on the dangers of following a low salt diet, and the steps you can take to improve health.
As has been noted, the author firmly believes that a lower salt intake is far more harmful than a high salt diet is.
Blood pressure? Blame that on sugar – which is also a leading culprit in the etiology of diabetes, cardiovascular disease, and kidney disease.
DiNicolantonio argues that the advice to curb our salt consumption is causing—rather than preventing—disease.
Further, he claims that a healthy intake of salt offers us better immunity, and improves our physical and emotional wellbeing.
The key? Just eat non-processed foods and add the right amount of salt – by following your taste!
What Does the Book Provide?
First, the book offers a look at the history behind the dietary guidance on salt and how it developed.
Somewhat similar to the demonization of saturated fat, salt too was an innocent bystander in the face of poor science.
With false accusations levied at salt, researchers would convince doctors and the general public on the necessity of reducing salt intake.
Additionally, the book hypothesizes how eating more salt might even save your life. Offering a detailed explanation, the book focuses on how sodium deficiency affects important health markers.
The book also provides the answers to all the questions you may have;
- Why the guidelines on salt are wrong and potentially harmful
- What is the healthiest salt?
- The importance of iodine
- How needlessly restricting salt may cause salt addiction
- How much salt is right for you?
Commenting on his book, the author writes;
My new book, The Salt Fix, takes readers through over 100 years of the history of the ‘Salt Wars’ and reveals the complete lack of evidence for population-wide salt restriction. I hope that after reading my book people will no longer fear the salt shaker and can finally start enjoying their food again.
– Dr. James DiNicolantonio, author of The Salt Fix.
It’s a great read containing some interesting research, yet written in a style anyone can understand.
If you want to read more about the book, then it’s available here.