Is it bad to drink water that’s been sitting overnight – or longer?

Since your body gets dehydrated overnight, it’s not uncommon to wake up thirsty. But whether or not you should sip from the glass you left on the bedside table (was it last night – or the night before?) is up for debate.

Here are 8 unexpected reasons you’re always thirsty.

You probably know that drinking water left in an open glass is not super sanitary. Dust, debris and even the odd passing mosquito can drop into the glass overnight, leaving an unhealthy surface scum. Even a closed container like a bottle or pitcher introduces problems, mainly because our skin is coated with sweat, dust, skin cells and even nasal discharge. Once we put the bottle in our mouth, these can all “backwash” into the remaining water, causing contamination.

Our saliva also carries bacteria, which does the same. “If it’s allowed to incubate for hours, that could potentially contaminate the water, and make you ill by reintroducing that bacteria,” says Dr Marc Leavey, a primary care specialist. “Once you have put your lips to the bottle, you should consume that bottle in one sitting and then discard it.”

You should also be aware of these 12 ‘healthy’ hygiene habits that are actually bad for you.

But let’s get real: Since it’s your own bacteria, it’s unlikely that you’ll actually get sick. Though no one brags about it, many people sip from used drinking glasses, mugs and bottles without any ill effects. But it’s certainly not advisable to share your bottle with someone else. Neither should someone with a reduced immune system, such as transplant patients, those undergoing chemotherapy, or people living with HIV/AIDS, be exposed to contaminated water.

And it makes no difference whether it’s bottled or tap water. It’s a common myth that bottled water is cleaner than tap. Both have to meet exacting hygiene standards.

So what about leaving water in places like your car? Water left in the sun will heat up, making it the perfect breeding ground for bacteria, especially if you’ve already drunk from it. Placing the bottle under your seat may reduce the heat a little, but bacteria will still grow.

Some kinds of plastic bottles contain BPA or similar chemicals, that may leach into the water, especially after exposure to sunlight. There is research suggesting that BPA is linked to a wide range of health problems affecting the brain and behaviour. Using a BPA-free bottle would eliminate this issue, but not the growth of bacteria, especially if you’re using a metal bottle, which heats up quickly, encouraging the germs to multiply.

Of course, staying hydrated is good for our health, so it’s important to recognise the signs of dehydration. Dr Leavey offers this advice to stay healthy: “Avoid putting your mouth to the bottle. Just pour it into a cup or pour it directly into your mouth.” To also keep yourself safe, don’t drink water that is past its expiration date.

Next, check out the facts that will make you stop using plastic.

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Source: RD.com