Sea salt


  • Sea salt contains a minimum 97% of sodium
  • Sea salt has a high moisture content (e.g. 14% in Celtic Salt)
  • The amount of iodine in sea salt is insignificant, so if you are in the Iodine risk group, use Iodized table salt or foods high in Iodine
  • The amounts of essential minerals are irrelevant to exert any significant health effect
  • There is a larger variety of toxic elements than essential minerals in sea salt. However, they are all within the safe levels.
  • Besides the known health effects of sodium and chloride, sea salt has no other proven health benefits
  • Sea salt is contaminated with micro-plastics more than other type of salt, which poses a potential health hazard. The full extent of the health consequences is still not well known.
  • Sea salt is worth as much as what you are willing to pay for its culinary properties. You shouldn’t pay more for non-proven health claims.


Sea Salt benefits – pseudoscience and false advertising?

False advertising campaigns and misleading health claims, enabled manufacturers to charge exuberant prices for the food-grade sea salt products.

It is true that sea salt is a more interesting alternative to table salt in a culinary sense.

If you are particularly interested in it, gourmet sea salt can add a sophisticated finishing touch to a meal.

It comes in a variety of colors, textures, grain size and structures. Some people even claim that they can detect differences in taste of the darker salts, depending on the mineral concentration. Even top chefs use specific salts that match their fine dishes.

If you chose to pay extra for a salt due to its special culinary qualities, then it is well justified.

However, if you decide to pay extra for the commonly advertised health benefits, then you are overpaying. Read below to learn why are the claims being made and why you shouldn’t listen to them.

What is Sea salt?

Sea salt is produced by evaporating seawater or water from saltwater lakes.

Solar evaporation (1) is the oldest method of salt production. This method consists of capturing salt water in shallow ponds, where it is evaporated by the sun.

The most common areas for harvesting sea salt are in the Mediterranean Sea, North Sea and Atlantic Ocean.

Depending on its geographical location, it varies in trace elements, contaminants or impurity content, which determines its color.

It includes essential for life trace elements and non-essential elements (usually toxic).

  • essential major elements, such as calcium, or phosphorus
  • essential minor elements, such as magnesium or potassium
  • essential trace minerals, such as iron or zinc
  • non-essential elements, such as toxic and radioactive elements (e.g. mercury and uranium)

Generally, the more impurities, the darker the color of the salt.

Currently, the major concern with sea salt is that it is being increasing polluted with micro-plastics (see the section below).


  • Sea salt is made from evaporating seawater or lake saltwater
  • Sea salt contains impurities, such as essential and non-essential trace elements, and micro-plastics from a polluted environment.

Iodine in sea salt

Contrary to popular belief, sea salt isn’t a good source of Iodine. It actually contains a very small amount of Iodine.

One study examined 81 samples of sea salt from 21 countries and found that all of them contained less than 0.7mcg (micrograms) of iodine per gram of salt, except for the Nigerian samples made from underground brine (1.4–6.5 mcg Iodine /g). (2)

These amounts are insignificant, when compared to the Iodine intake recommendations and other dietary sources of Iodine.

Iodine requirements for adults are 150 mcg per day.

The upper limit for adults is 1,100 mcg per day and for children between 200 and 900 mcg, depending on their age.(read more.)

In Australia the law states that iodine in salt must be in a concentration between 25 mg/kg and 65 mg/kg. (3)

In the U.S. all iodized salt contains 45 mg l/kg. (4)

Considering the limited amount of sodium that you can consume per day, the amount of Iodine derived from the diet is relatively more significant.

Some foods containing a high amount of iodine,  such as egg yolk (1,100 mcg/kg), cheese (240mcg/kg), cereals and grain products (6mcg/kg) are a much better dietary source of iodine than salt. (see more foods..)


  • Sea salt is not a good source of iodine, since it contains only trace amounts
  • If you are in the Iodine deficiency risk group, use either Iodized table salt or foods with significant Iodine contents

Most commonly claimed health benefits of sea salt

Just as in the case of Himalayan rock salt, there is a never-ending list of health benefits being attributed to this tiny amount of trace elements in sea salt.

A sample of the long-list of health benefits of sea salt that I found on various websites promoting this product is shown below.

Most of these websites are surprisingly popular and some of them claim to be written by doctors, which seems unlikely considering the amount of unscientific and unsupported information they contain.

None of these websites point to any peer reviewed, valid studies to prove these health claims.

The only links I found point to other layman websites or to poor-quality studies, often conducted or sponsored by salt manufacturers.

Depending on the source, sea salt is claimed to contain between 60 and 82 essential trace nutrients.

The consumption of sea salt supposedly has the following effects due to its abundant contents of trace elements:

  1. Is a great electrolyte source, helping in dehydration and fluids balance, not only because of its sodium-chloride contents, but also due to the trace elements it contains
  2. Helps in brain, muscle and nervous system functions
  3. Balances the blood/body pH and, therefore, has an alkalizing effect in the body
  4. Balances the blood sugar levels
  5. Eliminates mucus buildup
  6. Improves the immune system
  7. Increases energy levels
  8. Helps to promote a restful sleep
  9. Prevents muscle cramps due to its magnesium contents
  10. Regulates heartbeat and blood pressure

The list is much longer.

It seems as if someone just went through a textbook of the effects of minerals in human physiology and wrote down every possible function of each mineral.

In the following sections, I will show why, according to the available scientific evidence, these health claims have no merit.


  • Never-ending list of health benefits attributed to consumption of sea salt listed on the popular websites are not supported by scientific evidence
  • These popular beliefs are based on the properties of elements found in sea salt, even though their contents are insufficient to have significant effects on the body

Sea salt consists of insignificant amounts of both essential and harmful trace elements

By law, excluding the moisture content of salt, the food-grade salt contains a minimum 97% of sodium chloride based on dry salt, leaving only 3% maximum for other elements. Sea salt products usually contain not 3% but about 1.8% of trace elements.

Not only is the amount of essential trace minerals in food-grade salts insignificant, but there is a greater variety of non-essential elements, which include toxic and radioactive components, with unknown health effects. (5)

According to the analysis performed by the Western Analysis, Inc. for The Grain & Salt Society, light grey Celtic sea salt consists of 14% moisture, 33% sodium, 50.9% chloride and 1.8% of at least 75 trace elements.

Please note the high moisture percentage of sea salt.

Some sources claim that the amounts of trace elements are much higher in sea salt than in Himalayan salt. This is most likely due to the high moisture contents not considered in the calculations.

The bottom line is that the amount of both essential trace minerals and toxic elements is as negligent as in any other mineral – rich food-grade salts.

Claiming that this amount of minerals exerts health benefits is not only unscientific but also unrealistic. (6, 7, 8)


  • Legally any edible salt must have at least 97% of sodium chloride and maximum 3% of trace elements
  • Sea salt has approximately 1.8% of both essential and non-essential trace elements.
  • None of these elements exists in sea salt in a significant amount to exert either positive or negative effects on the body

Pollution raises concerns of heavy metals contamination of sea salts

Salt extracted from highly polluted areas may contain various types of contaminants.

Some popular websites and media sources express concern that because our seas are polluted with heavy metals, considerable amounts of these toxins can be also found in sea salt.

The fact is that the amounts of heavy metals (such as mercury) and other toxic elements so far do not pose a health risk and are insignificant compared to other dietary food sources. (read more..)

These amounts are not only within safe limits but are also much lower than in various gourmet salts, such as Himalayan salt, Hawaiian Sea Salt and other highly contaminated dark color salts.

Having said that, the growing pollution in the seas must be taken seriously and the quality of all salt products constantly monitored.


  • Heavy metal pollution of sea salt is on the increase. However, it is still within the safety limits.

Sea salt is contaminated with micro plastics

Other common pollutant in salts are micro-plastics, out of which polyethylene and polypropylene are the most commonly found.

Micro-plastics carry hazardous chemicals and microorganisms.

Either fragmented into small particles from large plastic objects, such as water bottles, plastic bags and medical waste, or directly introduced into the environment from plastic containing products, such as cosmetics, washing detergents, exfoliating body washes and textiles, micro-plastics are found in most water bodies, including the Celtic Sea where one of the most popular salt comes from. (9)

Everybody is now exposed to micro-plastics and unfortunately the full extent of its health impact is not known. Studies on the health effects of micro-plastics are difficult to conduct, since it is not possible to make a comprehensive comparison to those who haven’t been exposed to micro-plastics. (9, 10)

Micro-plastics are found in various amounts in salts, depending on their origins. They have been reported in salts in the UK, France, Spain, China and the U.S. Sea salt has the highest quantity of micro-plastics, while rock salt has the lowest.

For instance, salt sold in China (depending on the brand) has been found to contain the following amounts of plastics:

  • Sea salts: 550-681 particles/kg
  • Lake salts: 7-204 particles/kg
  • Rock salt has been found to have only a third of micro-plastics found in sea salt
  • Himalayan Rock Salt has not been reported to contain micro-plastics

 In addition to salt, micro-plastics are also found in the environment, foods and drinks (e.g. the air, water, seafood or beer).

The micro-plastics are tiny and only certain sizes are detected with the available technology.

55% of micro-plastics detected in these salts have 200 micromillimiters. (11)

Since there is not much information about the smaller particles, it is difficult to assess the full extent of the health risks associated with the plastic ingestion from salt. (12)

However, if you eat seafood, use plastic containers, cover your food with plastic foil and consume processed foods, then the amount of plastics from salt is comparatively insignificant. (12, 10)

My suggestion is if you are very conscious of what you eat, your diet consists of whole organic plant foods and you tend to avoid using plastic in food preparation or storage, then you might consider using Himalayan salt instead of sea salt.


  • The main concern related to food-grade sea salt is micro-plastic contamination which is constantly on the rise

Micro-plastics cause harm to organ tissues in humans and animals, although the full extent of damage in the human body is still being investigated

Is it worth paying that much for sea salt?

Just like in the case of Himalayan salt, sea salt has no unique health benefits other than what sodium and chloride contribute.

It only makes sense to pay more for sea salt, if you are basing your decision on its culinary properties rather than these false health claims.

However, if you are health conscious, rather than relying on salt as your source of trace minerals, you might consider including a wide variety of whole foods in your diet.  You should also be aware of the increasing levels of contamination of micro-plastics in sea salts.

NOTE: if you are in the iodine deficiency risk group, consider using iodized table salt. (read more..)


  • It only justifies paying extra for sea salt for its culinary properties
  • Ignore popular health claims attributed to trace minerals in sea salt
  • Consider other types of salt, if you are concerned about micro-plastics contamination

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