Health: Hydrate or stall, it’s your choice

by Karen Bowen

The past few weeks have given us our first taste of hot weather.

If you’re lucky – your truck has got air conditioning.

If not, give the old 260 air conditioning a try; crank down both windows and do 60 mph.

(Some things are more important than the best aerodynamics!)

Unfortunately – in the bright sun and warm temperature, it’s easy to become dehydrated.

All you have to do is sump out more water than you take in.

At first your body signals that it needs more water by making you thirsty.

But, if you ignore the signal and don’t get a drink, you’ll end up with dry skin and mouth; rapid heartbeat; low blood pressure; weakness and fatigue.

After thirst, dehydration’s next symptom is fatigue: a water loss of even one or two per cent of your body weight can make you weak.

Your muscles stop working their best.

By the time you experience a water loss of only seven per cent it’s likely you’ll collapse.

But this isn’t just a summer problem – your body is always losing water.

To get rid of wastes, your body must excrete at least a pint of water each day.

You lose more when you sweat (and these days, that’s likely happening a lot more.)

Even ordinary work may cause dehydration in this sweltering weather.

When your muscles work, they produce heat.

When they’re working hard, they produce 15 to 20 times as much heat as when they’re resting.

So you start to sweat to cool down.

Each litre of sweat dissipates almost 600 calories of heat – this prevents you from overheating.

Each litre of sweat cools your body temperature by as much as 10C.

As your blood travels through the capillaries just under your skin, the skin secretes sweat to evaporate and cool the skin and the underlying blood.

This cooled blood flows back to cool the deeper body parts.

This prevents an internal melt-down.

During intense physical activity, you also lose a lot of water through breathing.

Even your breath exhales water as a vapor.

The harder you breathe, the more water you lose.

But, there are other ways to become dehydrated.

Ongoing bouts of diarrhea can be serious.

What did you eat?

Food poisoning is the most likely cause.

But, sometimes diarrhea is a side effect of medications.

As well, if you’re trying to cut calories by eating sorbitol (sugar substitute) or olestra (fat substitute), too much of these products may also give you the runs.

To fix this, change your medications or diet, and drink lots of water.

Chronic diarrhea may also be a sign of a serious disorder of your digestive tract – for most people a low-fat diet and a gradual increase in fibre is helpful.

But, more serious medical conditions require close medical attention.

Caffeine can also cause problems. Drinking lots of coffee makes you dehydrated.

Because the caffeine in the coffee works as a diuretic, it means you pump out more water than you’re taking in from the coffee.

If you drink coffee to stay alert – wake up.

Too much coffee makes you tired because it lowers your fluid levels.

Drinking too much alcohol is another cause of dehydration.

Because alcohol makes your pituitary gland stop secreting the hormone that makes your body retain water, the more alcohol you drink, the more often you go to the bathroom.

As your body gets rid of more and more water … you get thirstier and thirstier.

If you quench your thirst by drinking more alcohol … you are actually drying your body out.

It’s a vicious cycle putting yourself at serious risk.

Your body needs water more than any other nutrient. All life-supporting activities take place in watery fluids.

So, don’t ignore your thirst.

Even if it’s a pain to get a drink or later, to find a bathroom.

Especially if you’re older, be cautious. Your body fluid percentage becomes lower over the years.

So for you, a slight water loss is quite serious. Just remember the old rule … at least two litres of water a day.

In the summer, you could double that. If you know that you’ll be sweating a lot later, (say if you’re about to drop off a load) start drinking now.

If you can’t face drinking all that water, there are tasty ways to keep your fluid levels topped up.

Here are just a few with their water content, as well: Diet caffeine-free sodas, 100 per cent; non-fat milk, strawberries, watermelon, lettuce, cabbage, celery, spinach, broccoli, 90-99 per cent; fruit juice, yogurt, apples, grapes, oranges, carrots, 80-89 per cent; shrimp, bananas, corn, potatoes, avocados, cottage cheese, ricotta cheese, 70-79 per cent; pasta, legumes, salmon, ice cream, chicken breast, 60-69 per cent; and ground beef, hot dogs, feta cheese, 60-69 per cent.

Delicious ways to prevent your engine from overheating and seizing.

Karen Bowen is a professional health and nutrition consultant and she can be reached by e-mail at


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