By James Razko
In this book summary of The salt Fix, you will learn that for most people, low salt diets are harmful to health, provide little to no benefit in blood pressure reduction, and are likely contributing to the plague of modern chronic diseases. Likewise, you will find that demonizing salt helped give sugar, the actual cause of many modern chronic diseases, a free pass for some time. You will also learn that when it comes to salt intake, your body knows best, and governments, prominent associations, and well-meaning scientists—got it wrong. And sadly, historical examples like believing in Zeus, knowing the world is flat, or suspecting ancient aliens once inhabited the earth, point to the fact that— beliefs die hard— no matter the evidence or logic.
I hope you enjoy this book summary of The Salt Fix.
Disclaimer
I am not a medical doctor. This blog post is a book summary of The salt Fix, and it may contain errors. The information presented here is for entertainment purposes only and is not intended to replace personalized medical advice. As always, consult with your doctor before making any changes to your diet. The blog and I expressly disclaim responsibility for any adverse effects that may result from the use or application of the information contained in this blog post.
Book Summary:
The Salt Fix: Why the Experts Got It All Wrong–and How Eating More Might Save Your Life, Dr. James DiNicolantonio
Four hundred and thirty million years ago, In a time that defies the limits of human imagination, our ancestors began taking the first steps towards life on land. For this exodus to happen, countless generations of creatures, had to develop a body that could survive the dry alien landscape. So, Evolution cleverly designed organisms that carried, like astronauts, all the things necessary to survive outside of the ocean with them, including the ocean’s mineral content—salt.
To this day, hundreds of millions of years and species later, our blood still closely resembles our birthing grounds—the salty water of the Precambrian era. We are 99 percent water— with a few pounds of salt. Our existence outside the brine is made possible thanks in part to our salt-regulation-system comprising of our kidneys, adrenal glands, and skin, which tightly controls our electrolyte balance. We need salt to survive and thrive.
Bad Salt?
Of course, there can always be too much of a good thing. For example, although it’s difficult, you can drown yourself, by drinking an absurd amount of water and not urinating.
So, are we consuming to much salt?
The author thinks not, and suggest many of us may need to consume more salt. In contrast, most will need to consume less sugar.
Let’s dig in and see how salt wrongly received a bad name.
The Salt-Blood Pressure Hypothesis
The salt-blood pressure hypothesis has been around since 1904. The theory, based on a hunch and six patients, basically states that: ingesting salt drives the body to crave and drink more water, and some of this water is retained by the body to dilute the extra sodium now in the bloodstream; the retained water increases blood volume, which causes increased blood pressure and eventually leads to hypertension; And, increased blood pressure puts strain on the cardiovascular system, resulting in premature death. This all sounds logical, but — it is wrong.
First consider that, human kidneys process about 1,452 to 1,633 grams (3.2 to 3.6 pounds) of salt per day. The average American consumes 8.6 grams of salt per day. Does it seem likely that a few additional grams of salt on top of the 3.2 to 3.6 pounds of salt will impose a problem to healthy kidneys— the author thinks this does not make physiological sense.
Furthermore, yes, salt does help the body retain water, but—this is a life-saving mechanism that allows us to survive dehydration.
Even more troubling for the salt-blood pressure hypotheses: studies have found that high salt diets decrease peripheral vascular resistance, causing blood vessel relaxation (good), while low salt diets increase peripheral vascular resistance (bad) putting stress on the cardiovascular system.
Even though in 1977, nobody understood what a low salt diet would do to the body, the Dietary Goals for the United States recommended Americans reduce salt intake—based on expert opinion. And, since that time, we have been told over and over that salt increases blood pressure, even though at the time of the recommendation mentioned above, the US Surgeon general conceded it had no idea if a low salt diet would indeed reduce blood pressure. It was all just expert opinion.
Since then, there has been a heated scientific debate, like no other, over salt’s effect on blood pressure. And, although there is still no consensus, the government and top health associations refuse to budge on their initial recommendation to reduce salt intake.
Salt and Blood Pressure
Does a low-salt diet decrease blood pressure? For many, it does not decrease blood pressure at all. And for those that do see a blood pressure decrease, it is very little. Let’s dig in.
Evidence suggests that about 80 percent of people with normal blood pressure, less than 120/80 mmHg are not sensitive to the blood-pressure-raising effects of salt—at all. Likewise, 75 percent of those with prehypertension and 55 percent of those with hypertension are also not at all sensitive to the blood-pressure-raising effects of salt. And, for the minority of people who are salt-sensitive (see a rise in their blood pressure when consuming salt), when the underlying issue of sugar consumption, which harms the kidneys (responsible for managing salt) is resolved, many find their blood pressure salt-sensitivity— disappears.
Research has found that reducing your salt intake to 2,300 milligrams will result in a 0.8/0.2 mmHg blood pressure drop. So, If your blood pressure were 120/80 mmHg before salt reduction, your new blood pressure would be an astounding 119/80 mmHg—not much to write home about. The previously noted reduction is so minuscule that it is likely to make no significant difference in your health whatsoever.
However, some low-salt advocates claim that a one-point drop in blood pressure could statistically save millions of people lives. And maybe they would be right if a low-salt diet didn’t also come with adverse health effects— but it does.
For example, scientists have known for some time that low-salt diets increase heart rate in nearly everyone. And, medical professionals agree that total stress on your cardiovascular system is a combination of blood pressure and heart rate. So, does a one point reduction in blood pressure outweigh an additional four beets per minute added to your heart rate? The answer, according to the author, is an emphatic—no.
So, if you’ve been a good patient and citizen, and have been reducing your intake of salt, heart rate is only the tip of the iceberg when it comes to a low-salt diet’s problems. Before we dive into the adverse health effects of a low-salt diet, let’s take a brief historical detour.
Salt Thermostat
Like water, the human bodies thirst for salt is a survival mechanism that has been wired deeply into our mammalian brains over millions of years of evolution. Evolution has gifted us with a nonconscious salt thermostat, which tells us through cravings and repulsion when we have consumed enough or too little salt.
Researchers have found that populations across the globe with unrestricted access to salt will consume 8-10 grams of salt per day (3,000 to 4,000 milligrams of sodium)— roughly 1 ½ to 2 teaspoons of salt. So it stands to reason that our distant ancestors, with access to ample salt, would have consumed the same amount.
A Salty Prehistory
Many anti-salt advocates mistakenly proclaim that our Paleolithic ancestors ate low sodium diets of 1500 milligrams or less per day because the environment lacked access to salt. And because our Paleolithic ancestor’s low-salt environment, we are wired to crave too much salt. Many of these claims stem from one influential paper that estimated paleolithic man’s sodium consumption to be around 700 milligrams per day.
The author believes the estimate above to be deeply flawed, pointing out that the calculation used only select land animals sodium content in their meat as well as available land plants. The estimate did not account for the sodium that paleolithic man consumed from tiger nuts, insects, aquatic vegetation and prey, and the large stores of sodium found in the organ meat, skin, blood, and bone marrow, all of which we know ancient man consumed.
When taking all of the previously mentioned food sources into account, the author concludes, it is clear that early man’s diet was, high in salt.
A Salty History Continued
We know that humans have been mining salt for at least 8,000 years. During human history, salt has been revered, sought after, fought over, traded, and even used as currency. For millions of years, salt was—essential and good.
Be that as it may, starting in the early 1900s salt began to be villainized, by scientists and governments searching for the cause of rising levels of hypertension in western populations.
The prevalence of hypertension before the early 1900s is unknown as the blood pressure cuff was not invented until the late 1800s. But, we do have data on the prevalence of hypertension in the early 1900s in the USA, and it is estimated that between 5 and 10 percent of the population suffered from hypertension.
Know, consider that in 1939, Chicago, that number jumped to 11-13 percent, and in 1975, the prevalence of hypertension reached a shocking 25 percent. But, it did not stop there. Today, 1 out of every 3 adults suffers from hypertension. So, What’s going on?
If we are to believe the salt-blood pressure hypothesis, surely starting in the early-to-mid-1900s, the average citizens salt consumption must have gone up along with the rise of chronic disease and death. However, as we are about to see, this is not the case, and if anything, salt consumption after the 1900s declined.
Before refrigeration, salt was the primary tool used to keep food fresh for long periods of times. This technique of food preservation resulted in many consuming considerable amounts of salt. For example, 16th century Europeans are estimated to have consumed 40 grams of salt per person per day, with some countries like Sweden consuming nearly 100 grams of salt every day, mostly from salted meats and fish. Over the last several hundred years, the author estimates that Europeans have consumed anywhere from 2x to 10x the amount of salt consumed today.
Now let us go back to the rise of chronic disease after the early 1900s. Records of salt intake for Americans in the 1900s are not easy to find, however, the military is known for bureaucracy and bookkeeping, and 40 years before the turn of the 20th century, salt rations for an American soldier during the civil war (1860-1861) included over 18 grams of salt per person per day, which did not include other sources of sodium from food. This number, 18 grams, can be used as a rough estimate for what salt intake of Americans may have been in the early-1900s.
You would expect, based on the salt-blood pressure hypothesis, that salt intake increased above 18 grams along with the rise of chronic disease. But today the average American who is statistically much more likely to suffer from chronic disease than someone living in the early 1900s consumes about 8.6 grams of salt per day—nearly half of the salt ration for our American Civil War soldiers.
We also know that after the 1930s, salt consumption was on the decline, thanks to home refrigeration units eliminating the necessity to salt foods for storage. Here we see that just as salt intake is decreasing in the early 1900s, hypertension is steadily increasing, doubling by 1975.
From our historical vantage point, it seems salt is an unlikely culprit for chronic disease, and if anything, a lower salt diet may have contributed to the rise of hypertension. So much for the salt-blood pressure hypothesis.
The Blame Game
So how did salt get the blame? Here’s what happened: Two scientists working in the 1900s noticed the surge of disease and looked for something to hold responsible. One guy in Europe thought it was sugar, and one guy in the USA thought it was salt. Tragically, the American who was not surprisingly the more vocal of the two scientists managed to sway popular opinion.
Soon after, scientists (jumping on the anti-salt bandwagon) started conducting a lot of bad research that seemed to prove the theory right. For example, one scientist bred a special kind of salt-sensitive rat that proved the salt-blood pressure hypotheses correct; the apparent flaw in his experiment being that you should not breed new types of rats so that their blood pressure is sensitive to salt to find out if salt causes high blood pressure— maybe science was different then.
Anyway, over the last one hundred years, there has been plenty of proper research that has shown salt was not the cause of chronic disease. But, most of it either got heckled by dogmatic anti-salters or went unpublished thanks to publication bias.
Publication bias is a phenomenon where research that does not show a significant outcome is three times more likely to go unpublished no matter how well it was designed.
So many scientific studies that find no significant relationship between salt and blood pressure, (basically exonerating salt) were and still are much more likely not to be published, leaving most of the published studies, no matter their quality, showing a relationship between increased salt intake and hypertension.
Meanwhile, other areas of research (showing significant results) pointed to another white crystal that might be responsible for the rise of chronic disease, and once again, history can give us a clear window to look through.
The Other White Crystal
As chronic disease across western civilization began to rise, so did the consumption of sugar. In 1776 Americans consumed about 4 pounds of sugar per person per year— or about 1 teaspoon per day. Later, in 1913, Americans consumed 76 pounds of sugar per person per year or as the author estimates— four large frosted cupcakes per day. By the 1920s, sugar consumption reaches 100 pounds per year, leveling off until the 1980s. And then, astonishingly, by 2002 the consumption of sugar sprung to 152 pounds of caloric sweeteners per person per year.
It is estimated that it takes two to three decades for a change in eating habits to cause a rise in disease across a population. Considering the previous data and the fact that heart disease rose dramatically to 20% of the US population in 1935, the author estimates that sugar reached a toxic threshold (around 76 pounds of sugar per person per year) between 1905 and 1915. Given this information, it should be no surprise that Americans living today, who are consuming an average of 152 pounds of caloric sweeteners per person per year are plagued by staggering levels of chronic diseases like type-2 diabetes, heart disease, and obesity.
During the 1960s in the US, when sugar consumption was around 100 pounds per person per year, 39 percent of all deaths were attributed to heart disease. During that same time, salt use was, as discussed before, on the decline thanks to the widespread use of refrigeration.
Sugar’s Free Pass
While salt was being demonized for the rise of chronic disease, sugar mostly received a free pass and was later aided by studies and research that were found to be backed by the sugar industry. For example, a meta-analysis (a review of studies) determined that 83 percent of studies (of sugar-sweetened drinks) with conflicts of interest found no evidence linking sugar-sweetened beverages to obesity, while 83 percent of studies with no conflicts of interest found a definite connection between sugar-sweetened beverages and weight gain and obesity.
Making things worse, some scientists and the sugar industry alike perpetuated the false idea that sugar is a neutral calorie and that obesity can be cured by simply moving more and eating less. To this day, this line of reasoning can still be heard from many health professionals.
However, as we know, a calorie is not a calorie, and different kinds of calories will affect the body in different ways. And, sugar, which is not a dietary necessity, affects the body in a myriad of negative ways when consumed as a refined product.
For example, one study found that by swapping wheat starch for the same amount of sugar calories, study participant’s fasting insulin and insulin responses to a sugar load increased, and as we know increased insulin response over time will contribute to chronic diseases like obesity and type 2 diabetes—a calorie is not a calorie.
Population Studies
Around the world, many countries enjoy a high salt diet and lack hypertension. On the other hand, there are no countries that consume a high sugar diet and lack hypertension.
Japan, France, and South Korea have the lowest rates of deaths from coronary heart disease in the world, and they also all enjoy and consume high-salt diets. However, despite Japan’s low death rate from coronary heart disease and boasting the longest life expectancy around the world, Japan has been used by anti-salt advocates for some time to try and prove their theory correct.
Anti-salters like to use Japan as an example because parts of the country, like Akita, have high rates of death from cardiac conditions like stroke and hypertension. Akita residents who consume around 27 grams of salt per day have twice the rate of death from stroke compared to other Japanese residents living in Aomori, who consume 15.2 grams of salt per day.
These findings are startling, and it is no surprise that anti-salt groups around the world have latched on to this data. But, researchers believe many factors like an unbalanced diet of too much rice, vitamin C deficiency, silicic acid in water and food, and cadmium exposure from food are contributing to the high rates of cardiac events. For example, cadmium is estimated to cause 17 percent of stroke cases in Japan. Even with all of the above mentioned contributing factors, researchers suspected that potassium, not salt intake, was the most significant contributor to the stroke rate in Japan.
So, the researchers put their potassium hunch to the test. In a study of 1,110 adults in Aomori, researchers found that increased apple intake was associated with lower blood pressure—apples are rich in potassium. This same effect was later observed in a clinical trial in Akita. And finally, a study of Japanese patients who consumed 15 grams of salt per day with essential hypertension found that by increasing potassium intake from 3 to 7 grams, their blood pressure would drop to normal. The problem was not salt in Japanese cities like Akita, but potassium deficiency.
Other Salty Folk
Many populations including: Italian nuns, Italian laywomen, Kuma Indians, Seventh-Day Adventist (vegetarians and omnivores), Mormon omnivores, Thailand, Samburu Warriors, inhabitants of Kotyang Nepal, North India, apple eating zones of Aomori Japan, Okayama Japan (in the summer), and rural Bantu consume anywhere from 3,000 to 6,000 milligrams of sodium per day and are healthy and nearly absent of hypertension. Importantly all of these groups consume approximately double the amount of potassium as Americans, sourcing most of their Potassium from adequate intake of fruits and vegetables.
Why Low-Salt Diets are Bad
When not ingesting enough salt, the body activates salt-retaining hormones. In the end, these hormones save your life in the short term but damage your body in the long term by harming vital organs, including enlargening and stiffening of the heart and blood vessels.
It’s important to note that our biological system naturally drives us to be in a sodium surplus to prevent dehydration, diarrhea, infection, and blood loss. This surplus is the optimal state for our body.
Below are some of the ways a low salt diet has been found to impact the body negatively. Low salt diets may cause:
- Accelerated hardening of the arteries
- Raised cholesterol and triglycerides
- Increased LDL (bad) cholesterol and decreased HDL (good) cholesterol
- Compromise kidney function
- Increased insulin resistance
- Increased sugar cravings
- Increased appetite
- absorbtion of twice as much fat
- Increased risk of overall dehydration
- Accumulation of visceral fat
- Increased fasting insulin from 10 to 50 percent
- Decreased blood flow to the liver and interferes with the liver’s ability to break down insulin
- Increased body fat
- Increased fasting and post-glucose by 25 percent
- Increased fatty acid synthesis in the liver, contributing to nonalcoholic fatty liver disease (NAFLD)
Some Pro-Salt Science
The Prospective Urban Rural Epidemiology (PURE) studied over 100,000 people in 17 countries and found that people consuming 3,000 to 6,000 milligrams of sodium per day had the lowest risk of death and cardiovascular events.
A meta-analysis of 275,000 patients found that consuming 2,645 to 4945 milligrams of sodium per day was associated with the lowest risk of death and cardiovascular disease.
Based on available data, less than 2,300 milligrams of sodium or more than 6,000 milligrams of sodium is associated with increased risk of death and cardiovascular events. Low salt intake is associated with a greater risk than high salt intake.
What Causes Hypertension
The author, through his research and the research of others, posits that a high sugar diet leads to weight gain, obesity, and type 2 diabetes, which is what ultimately causes hypertension. For example, many studies have found that when patients lose weight, their hypertension and salt-sensitive hypertension disappears.
Internal Starvation
Most people know by know that excess sugar leads to weight gain. And you now know that weight gain is the likely cause of hypertension. But, in a tragic turn of events, the author points out that a low-salt diet also contributes to weight gain, obesity, type 2 diabetes, and hypertension by putting your body in a state of internal starvation.
So, unfortunately, the recommendation to cut salt is likely contributing to the extra pounds around your waistline and thus increasing your likelihood to have hypertension in the first place.
Here’s why: The author believes internal starvation on a low-salt diet happens because insulin resistance and increased insulin levels are likely the bodies adaptation to a low-salt diet. As it turns out, Insulin helps the body reabsorb salt through the kidneys.
Increased insulin, both promotes fat storage and makes it difficult for the body to use these stores for energy. So, when insulin is high, the only macronutrient the body can use easily use is carbohydrate.
Without access to the bodies battery (adipose tissue), the body begins to crave more refined carbohydrates, which triggers the release of more insulin, which creates a downward spiraling cycle that ultimately leads to weight gain, chronic disease, and premature death.
Also adding to the downward death spiral, a low-salt diet, and high insulin levels promote a sedimentary lifestyle to both preserve sodium levels in the body and because the body can not access its fat stores easily.
You may be thinking: what about all the skinny people with hypertension. The thing is, thin people, can be fat too— they can be fat on the inside, aka skinny fat. You are skinny fat if you have high amounts of hard to see visceral fat (fat around the organs), which is ultimately more dangerous than the usual fat storage areas that you can see.
Low-Salt Addiction
Since our ancestor’s exodus from the salty Precambrian seas, our bodies have developed a dopamine-based reward system, giving us pleasure when eating salt, when salt-deprived. Low-salt diets that activate this reward system have been thought, because of the brain’s many overlapping pathways, to make it easier to fall victim to substance abuse. For example, sodium depletion has been found to cross-sensitize with amphetamine, which cross-sensitizes with cocaine.
Likewise, scientists have found that mothers with low salt levels during pregnancy will give birth to a child who will crave more salt throughout their life. Salt levels during pregnancy may act as an early salt calibration system for children. And some have theorized that a child calibrated to crave more salt will also be more likely to suffer from addiction.
It is important to note that salt is not addictive. For example, it is thought that once you meet your optimal levels of salt, your salt taste receptors move from positive (liking salt) to negative (disliking salt). Taste inversion is one of the bodies clever ways to keep salt levels inside your body at the optimal range.
Sugar is Addictive
On the other hand, sugar is addictive. And, researchers have found that structural changes in the brain, evidence of binging, and tolerance (all criteria for addiction) happen once sugar is introduced in both humans and animals.
For example, some researchers have found that a rat who is addicted to cocaine will prefer sugar when given the option between the two. This happens because, sugar, once eaten, creates a massive reward by releasing natural opioids and dopamine in the brain— making you feel (sugar high) good.
Also, sugar tolerance makes it harder to taste sugar and leads to increased sugar consumption and a dislike for food that is not sweet. Furthermore, sugar overrides the brains self-control mechanisms, leading to even more overconsumption. And, of course, overconsumption of sugar leads to chronic disease.
And, a low-salt diet will push you to find salt however you can, driving you to consume more food to increase salt levels. This extra food, of course, leads to weight gain, which adds to the death spiral we discussed earlier.
So, How Much Salt is Enough
The body unconsciously regulates our sodium intake to about 3 to 4 grams. The body’s salt thermostat which controls this set point keeps detailed data on incoming and outgoing salt levels. Sodium intake in the body is optimal when the amount of sodium ingested matches the amount of sodium excreted in the urine.
Most importantly, listen to your body; it will tell you how much salt to eat to stay in balance.
The optimal range of salt to ingested per day is somewhere between 3 and 6 grams (1.33 to 2.66 teaspoons), and some people may need more.
You may need to ingest more than 3 to 6 grams of salt if you:
- Consume a high-sugar diet
- Consume caffeine regularly
- Exercise intensely
- Are on a low-carb diet and or are intermittent fasting
- Are taking diuretics, antidepressants, and some diabetes medications
- Have kidney problems
- Have inflammatory bowel disease (IBS)
Exercise and Salt
When exercising, you lose sodium through your sweat. A person can sweat 1437 milligrams of sodium per hour exercising in a moderate climate or 2875 milligrams of sodium per hour in a hot climate. The author recommends salt dosing before, during, and after exercise to prevent dehydration and to perform optimally.
The benefits of salt dosing before during and after exercise include: less thirst, greater exercise capacity, improved performance, improved muscle gains, decreased risk of hyponatremia (low sodium in the blood), reduced risk of iodine deficiency, and improved kidney function.
When:
- Dose before exercise and every hour after while exercising.
How much:
- Moderate climate (below 80F): ½tsp salt
- Hot climate (80-89F): ½ -1tsp salt
- Very Hot climate (90F and above): 1-2tsp salt
Some ways to dose:
- Consume salt (or garlic salt) dry and rinse mouth after.
- Eat 3 large pickles or 5 olives and drink some of the corresponding juice.
- Dissolve salt in lemon/lime/orange juice and drink.
Conclusion
We do not ask people to limit their air, water, or food intake to the lowest life-sustaining amount. So, why do we ask millions to get by on as little salt as possible without evidence to support such a lifestyle? The author recommends listening to your bodies salt cravings, eating less sugar, and eating more (salted=tastey) vegetables to live a healthy life.
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