Sea salts are often extolled as being healthy due to their higher mineral content. The common table salt most people have in their salt shaker is made up primarily of sodium chloride along with added iodine. The trace minerals found in natural sea salt such as potassium, magnesium, and calcium are removed during processing. The argument for the health benefits of sea salt stems from the fact that natural sea salt retains these trace minerals. Although these minerals are undeniably important for health functioning of the body, if a balanced diet is followed, these minerals should be ingested in sufficient quantities from other sources.
Even more concerning is the fact that sea salt is a poor source for iodine which is found in significant amounts in table salt. Iodine deficiency is still a significant problem in many parts of the world and a deficiency can result in suboptimal function of the thyroid gland, giving rise to hypothyroidism and, in some cases, an enlarged thyroid gland or goiter. Although iodine is found naturally in seafood, milk, some meats, and eggs, many Americans don't consume high enough quantities of this element when iodine enriched salt is excluded from the diet. Table salt has continued to be one of the most important sources of iodine for Americans.
Another concern about the health benefits of sea salt is the fact that sea salt is derived from sea water which in some cases may be polluted. Sea salt isn't washed or boiled since this would remove the healthy minerals and trace elements which means when you buy sea salts, you're getting the raw salt, impurities and all.
A final problem stems from the fact that when people hear of the health benefits of sea salt, they may decide to sprinkle it in large quantities on everything they eat. This can result in an unhealthy sodium load which can lead to future health problems. Sea salt is a source of sodium just as table salt is and should be used in limited quantities.
One area where the health benefits of sea salt might be useful is in the bath. The minerals in sea salts have been shown to be effective for some skin conditions such as psoriasis with some psoriasis sufferers making pilgrimages to get sea salt directly from the Dead Sea. Dead Sea salts have also been shown in studies to help relieve symptoms of osteoarthritis and tendonitis.
If you decide to use sea salt in your diet, it's best to substitute it for no more than half of your normal table salt intake and continue to keep your total sodium consumption under 2,400 milligrams per day.