Food & Drink » Glenda Bartosh on Food

Food and drink: Salty snacks and non-sea water

Two- and four-legged creatures need the same summer pick-me-ups



It’s a guy thing not to drink water. Look around. Most of those Kleen Kanteen-toting and sipping fanatics are women. Sure, there are the jocks and the grizzled old guys whose kids gave them insulated water bottles for Father’s Day and they feel guilty if they don’t use them. But otherwise it’s mostly women who drink water.

My dad, my husband, most of my guy pals go ugh! when I offer a little water with lemon slices floating prettily on top to rehydrate after a few glasses of wine on the summer deck. Maybe I’ll have to rethink the lemon slices, because getting dehydrated and over-heated in summer aren’t exactly jokes.

When you sweat a lot you lose the salts (electrolytes) and water content in the interstitial spaces, the fluid-filled spaces that bathe the body’s cells. That’s why they put a pinch of salt in your lime drink in countries like Thailand and, if you get severely dehydrated, you need commercial powdered electrolytes or sports drinks to replace those salts along with the fluids.

People who are severely dehydrated also have decreased blood volume and low blood pressure, which will cause shock when severe. Heat stroke happens when your body’s cooling system can’t dissipate excess heat and eventually fails. Your temperature hits over 40 C (104 degrees F) ; you can suffer permanent brain damage or even die.

On the other end of the spectrum, over-doing the water thing can result in really painful heat cramps in your muscles — I know, I’ve had ’em. They happen when you drink so much water, it dilutes your body salts. Lots of manual labourers like roofers and steel workers suffer heat cramps, as do mountain climbers and skiers whose many layers of clothing can make them unaware of how much they’re sweating.

But when your body does become dehydrated and needs water, it responds in an amazing and automatic way (this from my Merck Manual of Medical Information ). The volume of blood circulating through the cardiovascular system decreases due to the lack of water. This decreased blood volume is perceived by receptors in the your neck arteries. They respond by sending impulses through the nerves to the pituitary gland, which is located at the base of the brain.

It produces an antidiuretic hormone that signals the kidneys to concentrate urine and retain more water. At the same time, the brain senses thirst, giving you a mighty urge to drink. And no, not beer or coffee   — both will dehydrate you further.