Sea salt is roughly 90% or more sodium chloride, the same compound that makes up table salt. The remaining portion, typically less than 10%, contains a mix of trace minerals including magnesium, calcium, potassium, iron, and zinc. These minerals give unrefined sea salts their distinctive colors and flavors, but they’re present in very small amounts.
The Main Minerals in Sea Salt
Sodium and chloride dominate the mineral profile of every sea salt, no matter where it’s harvested. Beyond those two, the most common minerals found in unrefined sea salt include magnesium, calcium, potassium, sulfur, and iron. Smaller trace amounts of manganese, zinc, phosphorus, and iodine can also appear depending on the water source.
The exact proportions shift based on geography, climate, and how the salt is processed. An unrefined sea salt that’s been minimally washed retains more of its original mineral content, while commercially refined sea salt goes through washing and processing that strips away most of those trace elements, leaving behind nearly pure sodium chloride.
How Different Sea Salts Compare
Not all sea salts carry the same mineral fingerprint. Celtic sea salt, also called “sel gris” or gray salt, gets its color from the extra magnesium, calcium, zinc, potassium, and iron it retains. Its sodium chloride content is notably lower than most salts: about 33% sodium and 51% chloride by weight, with the rest made up of moisture and trace minerals. That’s a significant difference from typical sea salt.
Himalayan pink salt, which is technically ancient sea salt mined from rock deposits in Pakistan, contains about 98% sodium chloride. It’s often marketed as containing 84 trace minerals, though most of those are present in extremely tiny quantities. The pink color comes from small amounts of iron oxide. Celtic salt, by contrast, contains around 34 trace elements but in higher individual concentrations because its overall sodium chloride percentage is lower.
Standard white sea salt from coastal evaporation ponds falls somewhere in between, usually at 90% to 95% sodium chloride with modest amounts of magnesium and calcium making up most of the remainder.
Do These Minerals Actually Matter Nutritionally?
This is where the marketing and the science diverge. While sea salt does contain minerals your body needs, the amounts are too small to make a meaningful contribution to your daily intake. Research on trace elements in mineral-rich salts has found that bioactive minerals like iron often exist in nearly insoluble compounds, meaning your body can’t efficiently absorb them. One analysis concluded that a significant contribution to recommended daily intake of trace minerals from salt “can be excluded.”
Consider the math: you’d need to consume dangerously high amounts of sodium to get even a fraction of your daily magnesium or potassium requirement from sea salt. The recommended sodium limit is less than 2,300 milligrams per day, roughly one teaspoon of salt. At that intake, the trace minerals from even the most mineral-rich sea salt barely register against what you’d get from a handful of spinach or a banana.
Sea Salt vs. Table Salt: Sodium and Iodine
Sea salt and table salt contain comparable amounts of sodium by weight, so switching between them won’t lower your sodium intake. The crystals may differ in size and texture, which can affect how much fits in a teaspoon, but gram for gram they deliver essentially the same sodium load.
One genuinely important difference is iodine. Iodized table salt provides about 78 micrograms of iodine per quarter teaspoon, covering 52% of the daily value. Noniodized sea salt provides virtually zero. The NIH lists sea salt as containing 0 micrograms of iodine per quarter teaspoon. If you cook exclusively with sea salt and don’t eat much seafood, dairy, or eggs, you could fall short on iodine, a mineral essential for thyroid function.
What Actually Sets Sea Salt Apart
The real differences between sea salt and table salt are practical, not nutritional. Sea salt’s coarser texture dissolves more slowly, which can create bursts of flavor on finished dishes. Its mineral content, while nutritionally insignificant, does subtly affect taste. Many chefs prefer flaky sea salt as a finishing salt precisely because those trace minerals add complexity that pure sodium chloride lacks.
Unrefined varieties like Celtic gray salt or fleur de sel also retain some natural moisture, which changes their texture and how they interact with food. These are culinary distinctions worth knowing, but they’re not health advantages. Your trace minerals should come from food, not from your salt shaker.