The planet is mostly covered in water. Our bodies are mostly water too.
The seas contain salt, and so do we, but the seas contain a lot more
salt than we can survive on; excess salt is toxic to humans. The effects
of drinking salt water vary--especially according to the volume and
duration of ingestion. Dehydration is one of the most common early
symptoms.
I was hiking with a friend of mine a couple of weeks ago, feeding him salty trail mix to keep his energy up.
A reasonable question, and a good one for the summer. Should you have salt while enjoying the hot weather?
The answer is maybe.
Water and salt coexist in your body. They need each other. Let’s anthropomorphize: the simplest explanation of their relationship is that they are codependent but salt is the bossy friend who calls the shots. Water follows salt.
Have you ever drink 100 plus or Gatorade which is an energy drink with salt as their main ingredient
The salt in the drink is the first thing to cross through your gut into the rest of your body. This makes your gut seek out water in order to balance the salt-versus-water concentration of the cells. Water follows the salt, and you get hydrated more quickly than if you had to wait for water to get through on its own.
In times of increased activity, say if you are jumping over small streams in Algonquin Park, you will lose both salt and water through your sweat. So consuming salt in combination with water is a good idea because it speeds up your absorption of the water, and also because you need a bit more salt than usual.
But if you are eating something salty and not very wet, your body will have trouble absorbing enough water to balance the salt. You will become thirsty and crave water – not Gatorade. Your body is adaptable, so your kidneys will do their best to get rid of salt and hold in the water until your thirst is quenched.
This leads me to a final thought which I have always found distressing: namely, the ocean is not like a sports drink. If you are stuck on a desert island, drinking the ocean will not hydrate you. The concentration of salt is so high that you cannot absorb enough water to balance it.
I guess my advice this week is, have a little salt while exercising and don’t get shipwrecked.
Kate Greenaway is a family doctor practising in Toronto. When not at work, she spends her time listening to public radio, reading vampire books and writing for TORO.
