This weekend I read the book The Salt Fix: Why the Experts Got it All Wrong – and How Eating More Might Save Your Life by Dr. James DiNicolantonio. I wasn’t sure I would get much value from the book since I’ve known for a decade now that the science behind the salt restriction recommendations was weak. But I did learn a lot.
Before I get to the summary, my quick review is that the author made a solid case that most of us do not need to restrict salt and in fact, some could benefit from a higher salt intake. (He did mention three cases where reduced salt intake might be appropriate: Hyperaldosteronism, Cushing’s disease, and Liddle syndrome.)
The part of the book I didn’t care for was his demonization of sugar as THE driver of obesity and other health ailments. Sugar likely plays a role in obesity and diabetes, but it is not the sole driver. See the charts on Carbohydrate, Sugar, and Obesity in America and then try to explain that sugar is THE cause of obesity and diabetes. Doesn’t work so well. Which means it is either something else or a combination of factors.
Notes for The Salt Fix
- Cold extremities might be a signal that you need more salt.
- Chronic salt depletion can increase insulin levels because insulin helps the kidneys retain more sodium.
- 8-10 grams of salt = 3-4 grams of sodium
- A person with normal kidney function and normal blood pressure can “easily” excrete 10x as much salt as a person would normally consume in a day.
- Early evolution foods were aquatic and had much higher levels of salt than the foods most commonly consumed today.
- “On average, our kidneys may filter between 3.2 – 3.6 pounds of salt (1.28 and 1.44 pounds of sodium) per day.” (p 28)
- Low salt intake stresses the kidneys and results in lower energy to avoid sweating. This could lead to weight gain.
- Romans consumed 25 grams of salt daily. 16th century Europeans 40 grams a day and 18th century Europeans 70 grams a day.
- Salt is anti-microbial. (As someone with extensive fermentation experience, I knew this.) This means that salt can protect from food-borne illnesses. Foods with lower salt levels tend to have a shorter shelf life.
- Increasing potassium can help regulate blood pressure, which helps reduce hypertension.
- Low carb dieters need an additional 2 grams of salt a day.
- Higher salt intake reduces stress/anxiety. (Remember my sleep dust post?)
- Salt is non-addictive. The body senses when it has enough and can sweat out the excess.
- Some people need more salt than others. People that exercise more and those of us that consume a fair amount of caffeine. If you sweat more in general, you’ll need more salt. This could be from a hot environment or sauna use. (Side note: During Army Basic training in the Georgia heat, my fellow soldiers and I, occasionally had to drink a full canteen of water with added salt.)
- The Salt Thermostat is a concept that the body has a set point for salt. This is a complex system that helps protect the body so it has the ideal salt level. When salt levels drop, the craving for salt increases.
- Consuming salt prior to and during exercise can help the body cool off faster due to increased blood circulation.
- More salt is needed during pregnancy and for breastfeeding mothers.
- The book lists 22 ways in which sugar causes salt depletion. (Some of these are a reach, but the take-home lesson is increasing salt and decreasing sugar is good advice for most people.)
- Higher salt is good for the skin when it is sweated out. It can fight off bacterial infections.
- The end of the book covers the pros and cons of different salts. The author likes Redmond Sea Salt the best.
Although it is not mentioned in the book, Dr. DiNicolantonio covered how salt might be preventive in tooth decay in the article This Surprising Mineral Can Counteract The Effects Of Sugar.
Another interesting tidbit from that article:
Salt also helps with digestion. Indeed, salt is made up of two essential minerals: sodium and chloride. Chloride is needed in the production of stomach acid, helping with digestion of food and absorbing nutrients
Although I have not been avoiding salt, I think I could increase my intake a little. Normally, I wake up and drink a few glasses of water, then drink coffee, and then go to the gym. What I’ll experiment with is consuming 3-5 grams of salt with water before my coffee and exercise.
The Salt Fix: Why the Experts Got It All Wrong–and How Eating More Might Save Your Life by James DiNicolantonio
UPDATE JUNE 2021: Check out Fact-checking The Salt Fix for a deeper dive into the claims made in the book.