We hear about it constantly. The problem with our diet is too much “salt, fat, and sugar.”
But is that really true?
If you’ve been following my work for a while, you know I wholeheartedly agree that excessive sugar is an issue and wholeheartedly disagree that fat is something we should avoid.
Pick up any health magazine or book and you’ll read about how salt will:
- make you puffy and bloated
- spike your blood pressure like crazy
- damage your heart and arteries
You’ll inevitably be reminded to limit your salt intake, remove the salt shaker from the table, and use herbs and spices in its place…
You know the drill.
But what if all these worries about salt were unfounded?
Aside from intentionally including salt in ALL of my recipes (including those in my freebie ebook, “Veggies: Eat Them Because You Want To, Not Because You Have To”), I really haven’t laid out the research for you.
After getting more than a few requests to cover this topic, it’s time to dispel some of the most common myths about salt.
Why We Need Salt
Salt is vital to the normal function of our bodies. The sodium and chloride it contains are key for:
- electrolyte balance (to keep your heart ticking and your cells talking)
- maintaining the correct plasma volume in your blood stream (regulates fluid levels)
- neural signaling (so you can think straight and move your muscles on command).
Salt also supports normal stomach acid levels by supplying chloride (remember stomach acid is hydrochloric acid). Adequate stomach acid is necessary for the absorption of minerals and vitamin B12, protein digestion, and killing off pathogenic bacteria (and other ickies) before food leaves our stomach. In addition, salt plays an important role in food preservation, preventing unfriendly organisms from growing in our foods in the first place.
That said, the pervasive opinion in the medical and nutrition world is that salt is something we need to limit.
But before you cut back on salt, you’ll want to read the top 5 myths about salt. You might be surprised by what the research really says.
Top 5 Myths About Salt (and why less isn’t always better)
Myth 1: We Eat Too Much Salt
Despite the media continually harassing us for eating more salt than ever, there’s just not data to back that up.
Dietary recall studies are notoriously inaccurate. In short, we lie about what we eat. (Int J Obesity, 2015)
The most accurate measure of sodium intake is via 24 hour urinary sodium excretion (how much salt is in your pee) because about 95% of daily dietary sodium is excreted in the urine.
An analysis from Harvard of 38 studies from 1957 through 2003 show pretty consistent urine sodium excretion across 5 decades. In other words, Americans eat the same amount of salt as we always did (~3700 mg of sodium/day). (Am J Clin Nutr, 2010)
But somehow hypertension rates have increased dramatically since the 1980’s. Why?
There are a lot of reasons, but we can’t single out salt.
Myth 2: Salt Raises Your Blood Pressure
Not so fast, friend.
Salt doesn’t always cause your blood pressure to go up.
In fact, according to researchers from the University of Virginia School of Medicine, only about 25% of the population is salt-sensitive. And 15% of the population have increased blood pressure on a low-salt diet. (Clinica Chimica Acta, 2013)
That’s right. There’s no guarantee that eating more salt is always harmful or that reducing it is always beneficial.
In one recent study, salt intake had a “statistically insignificant” impact on blood pressure levels in individuals without preexisting hypertension. (Amer J Hypertens, 2015)
Similarly, an analysis of the extensive National Health and Nutrition Examination Survey found no link between sodium intake and blood pressure (even after adjusting for age, sex, race, body mass index, diabetes, and estimated glomerular filtration rate <– that last one is a measure of kidney function). (J Clin Hyperten, 2014)
Even the conservative Academy of Nutrition and Dietetics (which guides the practice of dietitians in the US) suggested removing salt from the “nutrients of concern” list in 2015, expressing “concern over blanket sodium restriction recommendations in light of recent evidence of potential harm to the larger population.”
That’s a BIG move for an organization that’s extolled the benefits of salt restriction for decades.
If anything is clear from recent research, it’s that salt does not always raise blood pressure.
Myth 3: Eating Less Salt is Healthy for Everyone
Like I mentioned above, only 25% of the population is salt-sensitive (and therefore DO need to watch their salt intake).
But what about the remaining 75% of us?
Isn’t it still dietary common sense to eat less salt?
“The relationship between salt intake and cardiovascular risk is not linear, but rather fits a J-shaped curve relationship. Thus, a low-salt diet may not be beneficial to everyone and may paradoxically increase blood pressure in some individuals.” (Curr Opin Nephrol Hypertens, 2013)
The study authors goes on to explain:
“There are other potentially harmful effects of low salt intake, leading to plaques and ultimately blockages in the arteries.” – Robin Felder
Even more concerning is the significantly increased mortality rate (death rate) associated with below-usual sodium intake. (Amer J Hypertens, 2015)
Unfortunately, deciding who should eat more or less salt isn’t crystal clear.
Some people have kidney problems or take medications that require a low-sodium diet, but when it comes to salt-sensitivity, there’s no consensus in the literature for how to unmistakably identify folks who are or are not salt-sensitive. (Not yet, anyways. That’s an area of research that Robin Felder and others are exploring.)
But there is one thing that causes people to become salt sensitive…
Myth 4: Salt Sensitivity Is Always Out of Your Control
We know there are some genetic factors that can influence salt-sensitivity, but it turns out what you eat plays a major role.
(Shocking, I know…)
It turns out that excessive intake of sugar, especially fructose, can trigger salt sensitivity.
“Animal studies have shown that high-fructose diets up-regulate sodium and chloride transporters, resulting in a state of salt overload that increases blood pressure. Excess fructose has also been found to activate vasoconstrictors, inactivate vasodilators, and over-stimulate the sympathetic nervous system.” (J Hypertens, 2015)
And if you’re tempted to ignore that study because it’s not done on humans, check this out:
A systematic review of 12 studies on sugar-sweetened beverage intake encompassing 409,707 individuals came to a consensus (rare in the literature, by the way).
All 12 studies found that the more sugary beverages people drank, the higher their blood pressure (and this correlation was statistically significant in 10 of the 12 studies). (Amer J Cardiol, 2014)
What sweetener is used in the majority of sugar-sweetened beverages?
Why, high-fructose corn syrup, of course!
If we’re gonna bother with a public health campaign to lower blood pressure, our focus should be on SUGAR (particularly refined fructose), not salt.
In addition, diets high in added sugar are unmistakably linked to the risk of excess weight gain. Not surprisingly, hypertension and obesity tend to go hand in hand.
And there’s plenty of researchers pointing this out:
The “epidemic of obesity may be a more important determinant of the increased prevalence of hypertension than sodium intake.” (Am J Clin Nutr, 2010)
Myth 5: I Have High Blood Pressure, So a Low-Salt Diet is Right for Me
Maybe, but maybe not.
The majority of salt intake in the American diet comes from processed foods – about 75% (Curr Opin Nephrol Hypertens, 2013).
So if a “low-salt” diet just means cutting back on processed foods (in other words, eating more real food), you’re on the right track.
You might be surprised to hear that 36% of the sodium consumed in the US comes from cereal and cereal-based products – the greatest contributor, by far, compared to all other food groups.
(Side note: This begs the question – Have we unfairly blamed salt for high blood pressure rather than processed carbohydrates? Did researchers fall for the Nutritionism Trap by focusing solely on sodium?)
If you’ve been eating more bread, cereal, and oatmeal in the name of health, you’re probably not doing your blood pressure any favors – and not just because of the sodium content (read The Healthy Breakfast Mistake and CGM Experiment for more on that).
Breads and cereal products are high in carbohydrates. And it turns out lower carbohydrate diets have been shown to “decrease the severity of hypertension.” (Nutrition, 2014)
Low-carb diets are also highly effective tools for weight loss and normalizing insulin/blood sugar levels, both of which directly impact your blood pressure. (Nutrition, 2015)
Most people become more efficient at excreting sodium via the kidneys on a low-carbohydrate diet (so much so that you may need to diligently eat more salt on a low-carb diet, as explained in this post).
All details aside, if you focus your efforts on eating more unprocessed, real foods, you may see big improvements in your blood pressure.
One analysis that tested the feasibility of a low-sodium diet (in other words, how to comply with the diet in the real world), found:
“The lowest-sodium food patterns that were nutrient-adequate and theoretically achievable were very high in fruit juices.” (Amer J Prevent Med, 2012)
But fruit juice is a highly concentrated source of sugar (especially fructose). That’s no bueno considering that fruit juice intake is linked to weight gain (see 5 Signs You’re Eating Too Much Fruit for more on that).
And remember how blood pressure responds to fructose? (for a refresher, see myth #4)
So if you have high blood pressure and you have a few extra pounds to lose, you’ll want to steer clear of fruit juice, sweetened beverages, high intakes of grain products and eat more fresh, unprocessed food in its place.
What Type of Salt is Best?
Now that we’ve worked through the top 5 myths about salt, you’re probably wondering what kind of salt is best to eat.
I prefer to use unrefined sea salt. It tastes better (in my opinion), doesn’t have added “flow agents,” (chemicals to keep it from clumping in your salt shaker), and contains a variety of trace minerals. (J Sensory Studies, 2011)
The only downside of sea salt is that it doesn’t contain much iodine (most refined salt is iodized) and this is a key nutrient for thyroid function and prenatal health, among other functions.
Knowing that, I make sure to consume other sources of iodine in my diet – fish, seaweed, eggs from pasture-raised chickens, and grass-fed dairy products (if you’re not sure you can tolerate dairy, read this).
Let’s all just relax a bit about salt. Remember, 75% of us are NOT salt-sensitive. Most of the salt Americans consume comes from processed foods.
When you’re cooking at home, you’ll need salt to make your food taste good, especially bitter green vegetables (kale chips, anyone?).
If your struggle with sticking to a real food diet centers around food being “tasteless” or “bland,” you’re probably not using enough salt when you cook.
And contrary to popular belief, when your food tastes good, you’re often satisfied with less. Many of my clients are surprised they can lose weight and maintain it eating such a tasty diet!
(Full disclosure: I swear if you put a bag of low-sodium chips in front of me, I’ll polish off the whole bag, but give me the real deal and I’m satisfied with a handful. It’s as if my body isn’t satisfied until it’s had enough salt… Unlike most dietitians, if a product says “low sodium” I’m much less likely to buy it.)
If you’re cooking most of your food from scratch and at home (and particularly if you lean towards a lower carbohydrate diet), you probably have more wiggle room in your diet for salt than you think. Similarly, if you exercise a bunch and sweat heavily, you’ll want to ensure you’re eating enough salt.
Lastly, if you’re pregnant, you might need to pay even more attention to salt. It turns out that sodium needs go UP in pregnancy. Read more on that here.
Until next week,
PS – For tips on how to make vegetables taste good, suggestions for how much salt to use (and recipes which all measure the amount of salt so you don’t have to be a master chef to get it right), grab a copy of my free ebook below, “Veggies: Eat Them Because You Want To, Not Because You Have To.”
Join thousands who are finally enjoying veggies thanks to this freebie! When you know how to make real food taste good, you’ll be less tempted by processed foods.
PPS – Before you go, I’d love to hear from you.
- Do you limit your salt intake? Why or why not?
See you in the comments below!
UPDATE: If you have questions about salt related to babies, I recommend you read my in-depth article on salt & baby food. Many people are warned not to give their babies any salt, but are the infant sodium requirements really accurate? Read more on this here.