The human body needs around 27 main micronutrients. No mineral has ever been as loved and hated as salt. From the precious resource of the Roman Empire to the topic of controversy in many laboratories, salt definitely has quite a reputation. Because of that, as a registered dietitian, I am going to answer all of your questions regarding this disputed topic:
- How much salt do you need?
- Why are we born with salt receptors?
- Are there any benefits to salt?
- The negative aspect of salt
- The controversy around salt
The good: how salt saved us three times
Did you know that felines don't have sweet receptors? And sea lions don't have receptors at all? There is a good reason for it. They don't serve them. Felines are carnivores, therefore detecting fruits rich in glucose and fructose is not essential. Sea lions, on the other hand, swallow their prey directly, no matter how it tastes. Based on this information, there must be a reason why we developed salt receptors, don't you think?
Evolution: the chance to settle down and preserve our food.
The main reason why food spoils is because of the presence of water. This is the ideal medium for bacterias to reproduce. Can you imagine the surprise of the first men when they realized this crystal can save their food from getting rotten? This was a huge improvement because it meant humans no longer had to chase animals and they could finally settle permanently. Having more available food helped them also dedicate more time to other activities.
Taste: salt covers the bitter taste.
While many chefs can confirm that adding salt gives more texture and flavor, it can also make us eat undesirable food. Salt can partially neutralize the rancid taste. This allowed us to eat foods that otherwise we may have kept a distance from. Taste also changes based on our age. Most young children have an aversion to even slightly bitter foods. This is likely the remnants of a defense mechanism against many toxic and poisonous plants — which also have a bitter taste.
Anatomy: how our body took advantage of this extra mineral.
Did you ever drink seawater as a kid, just to shortly realize you are more thirsty than ever? Salt has the great ability to regulate and balance your intra and extracellular fluids. That's because salt is a huge player in osmosis and your body uses this tool to its advantage. It is also useful to contract muscles and make your heartbeat more efficient. Just like everything in your body, there is a special equilibrium that shouldn't be altered too much. Too little salt can be detrimental to the overall extra and intracellular volume. On the other side, having too much salt will deplete water from your cells, making you more thirsty than ever.
The bad: how to overwhelm the system
As I mentioned before, there is a fine equilibrium that needs to be maintained. The challenge is not really salt itself, but the difficulty the body has getting rid of it. The kidneys get overwhelmed when eliminating it and the remaining sodium in the blood must be diluted with water. More water is not always better.
More water in the blood = more volume and more pressure for the heart to pump (hypertension). The artery walls need to thicken in order to deal with the blood pressure.
How to avoid it?
1. Consume less salt
According to scientific studies, the optimal daily intake should be around 5g = 2000 mg of sodium. In Western countries, the current consumption is around 10g = 4000 mg of sodium, with Eastern Europe touching 13g of daily salt. Reducing salt can be easier than you think. Did you know that 75% of dietary salt comes from processed foods like: canned goods and fast food. Only 25% is added during cooking or occurs naturally in foods. Don't feel guilty anymore for adding salt, instead reduce the amount of processed foods.
2. Increase potassium
The results from a meta-analysis from 2018 suggest to increase the potassium intake instead of reducing salt. Potassium and salt are both electrolytes and increasing the level of potassium creates a stable balance in the body. Adding more potassium-rich foods like green vegetables also helps reduce the amount of processed foods.
3. Weightloss and hydration
In addition to potassium, other factors have shown promise in lowering blood pressure and hypertension risk, including losing weight (generally measured by body mass index) and increasing hydration levels.
The ugly: Not enough evidence
Most studies are based on the 25% of the population, which is “salt sensitive,” meaning their blood pressure rises as dietary sodium is increased. However, around 75% are insensitive to moderate increases and decreases in dietary salt. The main criticism regarding salt recommendation is that it is mostly based on studies of salt-sensitive individuals.
According to a 2013 study, 11-16% of individuals are inverse salt sensitive and need to consume a higher amount of sodium to prevent high blood pressure. Some individuals require up to 10g of salt per day (2 teaspoons) to lower blood pressure into the range considered safe by blood pressure guidelines (<120/<80 mm Hg). This means that not all individuals can benefit from a low-salt diet.
Himalayan salt (= pink salt)
The pink Himalayan Salt trend started in 2009. The main reason for this boom is the presence of 25 extra micronutrients. Some blogs claim that there are more than 86 nutrients, but in recent studies, I found only a list of a maximum of 25 nutrients. From 31 samples examined, only one brand contained excessive amounts of lead, more precisely (2.59 mg/kg), when there is a maximum contaminant level of 2 mg/kg allowed per salt.
While you definitely have positive nutrients like:
You also find nutrients like:
From 31 samples examined, only one brand contained excessive amounts of lead, more precisely (2.59 mg/kg), when thre is a maximum contaminant level of 2 mg/kg allowed per salt.
But all of this doesn't really matter ...
... because the amount of nutrients is so marginal. You would need to eat 592% more salt a day just to get any value out of these nutrients. This would be too harmful to your health. It would be much easier to get these nutrients from fruits and vegetables.
Now you have a complete overview of this essential, yet controversial, micronutrient. Make sure to save this blog article and share it with your friends. Help me spread nutritional advice based on science!
Gildea, J.J.; Lahiff, D.T.; Van Sciver, R.E.; Weiss, R.S.; Shah, N.; McGrath, H.E.; Schoeffel, C.D.; Jose, P.A.; Carey, R.M.; Felder, R.A. A linear relationship between the ex-vivo sodium mediated expression of two sodium regulatory pathways as a surrogate marker of salt sensitivity of blood pressure in exfoliated human renal proximal tubule cells: The virtual renal biopsy. Clin. Chim. Acta 2013, 421, 236–242.