Molecule of the Month: Something Salty.

My last post ended on the topic of desalination, which is something California (amongst other regions around the globe) is starting to resort to as a consequence of a low drinking water supply. This post goes a step further by diving into the nitty gritty of sodium chloride (NaCl).  Salt, for short. 

With all of these fun themes (Spring is Coming, Winter is Coming, Tools of the Trade, How to Kill A Plant, and Sex is Weird) floating around on FTDM, we thought you would appreciate a molecular parallel to our Mutualism of the Month.  So, without further adieu, now introducing the first post of:

Molecule of the Month !
The molecule of this month being none other than salt.
No, I'm not talking about the movie.  I'm talking about that white stuff you sprinkle on nearly every meal, every day.  Why is that?
Well, a lot of it has to do with Biochemistry.  In fact, your tongue has special mechanical receptors on its surface that are used to recognize salt/saltiness.

A collection of taste receptor cells making up a "taste bud" on the tongue.  (Discover, Huang et al 2006)

A collection of taste receptor cells making up a "taste bud" on the tongue.  (Discover, Huang et al 2006)

Our body NEEDS salt.  Again, this roots back to Biochemistry.  If we take a moment to look at the structure of salt, NaCl, what we see is the following:

Left: A lattice structure of salt (sodium = Na, chloride = Cl) showing how the atoms bond with one another. Right: A large scale, visible view of salt crystals as a result of this lattice formation.

Left: A lattice structure of salt (sodium = Na, chloride = Cl) showing how the atoms bond with one another.
Right: A large scale, visible view of salt crystals as a result of this lattice formation.

Now that we have an idea of the structure and formation of salt, let's consider its properties.  The ionic bonding that occurs between Na(+) and Cl(-) makes salt a very good conductor, ESPECIALLY when it is dissolved in water (causing the ions to separate). This means that it is good for allowing electric charges to flow smoothly.  That's why recipes always recommend to boil your pasta with a pinch of salt - it helps distribute the energy being used to cook your food!  In a similar way, that's why WE need salt.  Our body is one big conductor, making salt critical for providing this conductive environment inside of us.  This allows us to take up nutrients, think, move, and do any daily task, really.  Our bodies don't make salt naturally, which is precisely why we NEED it.

Where do we get salt?
Salt is everywhere, but we usually obtain it from saltwater sources (fellow Salt Lake City, Utahns - I'm looking at you).  This topic hits close to home for me growing up right next to the Great Salt Lake, which comes in as the 2nd saltiest body of water when compared to the Dead Sea.

The process of obtaining salt is fairly straightforward:

There are many different "types" of salt (kosher, crystalline, rock, Himalayan), but is there really a difference?  Yes and no.  The major differences between any kind of salt is how it is processed and where it was obtained.  The main thing to keep in mind is that, when it all boils down (pun intended), salt is still Na-Cl, nothing more and nothing less.  A label that tells you differently is telling you that something else has been mixed with the salt.  For example, it's common to see "Iodized Salt".  This is because iodine is not typical in an American diet, but we need iodine in our diet, and so it is mixed with salt.  We also see this with Vitamin D, which is commonly mixed with whole milk (though it is not naturally a large part of whole milk).  The same goes for pink salt.  The pink color is from the presence of iron (Fe) atoms, not from the salt (which is colorless).  So, there may be different "types" of salt in existence, but the reality is that salt can only be salt.

In summary, we've learned why we need salt, how it is formed, where it comes from, and the truth behind salt "types".  

Questions? Comments? Confusions?