If you’ve ever stood in the grocery store staring at shelves of salt—table salt, kosher salt, Himalayan pink salt, Celtic sea salt—you’ve probably wondered:
Does it actually matter which one I use?
The short answer: yes… but maybe not in the way you think.
While most salts are nearly identical at their core, the differences in processing, additives, and trace elements can influence flavor, fermentation outcomes, and even safety considerations over time.
Salt Basics: It’s (Almost) All the Same
At a chemical level, nearly all culinary salts are 97–99% sodium chloride (NaCl).
That means:
- A gram of salt = roughly the same sodium, regardless of type
- The real differences come down to:
- Crystal size
- Additives (like iodine or anti-caking agents)
- Trace minerals or contaminants
One important distinction:
- By weight, salts are interchangeable
- By volume, they are NOT
A tablespoon of fine table salt will taste much saltier than a tablespoon of coarse kosher salt. To learn more about this check out my video on Lacto Fermentation Salt Ratios (without a Kitchen scale).
The Main Types of Salt (And When to Use Them)
1. Iodized Table Salt
What it is: Highly refined salt with added iodine and anti-caking agents
Pros:
- Affordable and consistent
- Helps prevent iodine deficiency
Cons:
- Can taste slightly metallic
- Not ideal for fermentation
- Less desirable for finishing dishes
Best for: Baking, pasta water, general cooking if you want built-in iodine
2. Non-Iodized & Kosher Salt
This category includes:
- Pickling/canning salt
- Non-iodized “sea” salt
- Kosher salt
Pros:
- Clean, neutral flavor
- No iodine or additives (in most cases)
- Dissolves easily
Cons:
- Kosher salt varies by brand—so measuring by weight is more accurate than volume.
Best for:
- Everyday cooking
- Fermentation
- Recipes where consistency matters
3. Natural Sea Salts (Celtic, Grey, Fleur de Sel)
These are minimally processed salts evaporated from seawater.
What is it: Often moist, flaky, or grey, more complex flavor, Ccn taste slightly briny or mineral-rich
Best for:
- Finishing dishes
- Adding texture and visual appeal
Consideration:
Because they’re less refined, they may contain:
- Trace heavy metals
- Microplastics from ocean contamination
4. Mined “Ancient” Salts (Himalayan, Redmond Real Salt)
Sourced from ancient seabeds, these salts get their color from minerals like iron.
What is it: Mild, slightly earthy unrefined salt.
Use:
- All-purpose or finishing
Reality check:
Despite marketing, these are still mostly sodium chloride with tiny amounts of additional minerals.
Taste Matters More Than You Think
From a culinary standpoint, salt choice really comes down to function:
- Everyday cooking:
→ Non-iodized or kosher salt - Finishing:
→ Flaky or mineral-rich salts - Baking:
→ Fine, consistent salt (usually table salt)
A simple kitchen upgrade, have two salts:
- A reliable “workhorse”
- A finishing salt you enjoy
Salt and Fermentation: What Actually Matters
When it comes to fermentation, salt choice becomes more important.
Research on fermented foods like kimchi shows that mineral-rich salts can influence bacterial activity, including strains like Leuconostoc and Lactobacillus, which shape flavor and fermentation outcomes. *This study actually uses two relatively refined salts but with additions of minerals found in the ocean.
However, for consistency and safety, the best choice is:
Non-iodized
No anti-caking agents
Predictable composition
With all that said, I have two different recommendations:
- Pickling salt – clean, consistent, basic.
- Non-iodized unrefined salt – more nuanced, and perhaps more/different probiotics created
While “fancy” salts can work, their moisture and mineral variability can make results less predictable. This is especially important if you’re teaching or repeating recipes. But, for interest and personal preference, and as the study shows, perhaps those with more minerals create a different nutrient, and taste profile.
Iodized vs. Non-Iodized: Do You Need Iodine?
Iodized salt has played a major role in preventing iodine deficiency.
If you primarily use non-iodized salt, iodine needs to come from elsewhere:
- Seafood
- Dairy
- Eggs
- Supplements (if needed)
From an RD perspective, this isn’t about avoiding iodized salt—it’s about being intentional with your iodine intake which is especially important for those with thyroid concerns.
Heavy Metals in Salt: What the Research Actually Shows
Let’s talk about the concern that’s getting the most attention lately.
What’s been found?
Studies show that most salts contain trace amounts of heavy metals, including:
- Lead
- Arsenic
- Cadmium
- Mercury
However:
- These levels are generally very low and considered safe
- Most fall well below established safety thresholds
For example:
- A systematic review found hazard levels far below concern for both adults and children
- Analyses of cooking salts found contaminants either extremely low or undetectable
Refined vs. Unrefined Salt
Some findings suggest:
- Unrefined salts (rock/sea):
Slightly higher trace elements - Refined salts:
Lower contaminant levels due to processing
Important nuance: Many trace elements in rock salt are poorly absorbed (low bioavailability), meaning they may not significantly impact the body. Per this study: ” In most samples, the concentrations of trace elements in rock salt were too low to show biological effects. Salt can therefore only significantly contribute the essential elements sodium, chlorine, and, if added on purpose, fluorine and iodine to human nutrition”. The study then said, even if solubility and bioavailability are 100%, the levels are so low effects are minimal.
So… Should I Be Concerned?
This is where context matters. There’s no need for alarm—but there is room for thoughtful choice.
If you’re in a higher-risk group:
- Pregnancy
- Young children
- Concerned about cumulative exposure
You might consider:
- Using refined or kosher salt as your daily default
- Using mineral-rich salts occasionally as finishing salts
For Most People
The biggest health factor is still total sodium intake, not trace minerals. Plus, our lack of fiber and anti-inflammatory, gut loving phytonutrients – both found in fruits & veggies!
your dietitian friend
Putting It All Together
Here’s a simple, realistic approach:
For most households:
- One everyday salt (non-iodized or kosher)
- One iodized salt (if dietary iodine is low)
- One finishing salt you enjoy
For fermentation:
- Stick with non-iodized, additive-free salt
For those concerned about heavy metals:
- Default to refined salts
- Use “natural” salts in small amounts
Final Thoughts
At the end of the day, choosing salt comes down to three things:
Flavor. Function. Personal preference.
Yes, there are differences—but they’re often subtle, and context matters. For most people, the bigger picture of health isn’t which salt you choose……it’s how your overall diet supports your health over time.