How to avoid dehydration in winter

You might not be panting and sweating during winter workouts, but it’s still important to pay attention to how much fluid you take on board. Here’s how to recognise and avoid dehydration in winter…

Feeling fatigued and foggy headed? Perhaps, you’re not drinking enough. The body is about two-thirds water, and when the total water level drops by only a few percent, we can become dehydrated.

Of course, while most of us pay extra attention to how much we drink during summer workout sessions, taking big bottles of water to the gym and using hydro packs on runs and hikes, by the time winter rolls around, drinking enough slips to the back of our minds. And this makes sense – hot-weather exercise is a thirst-inducing affair – but you still need stay to hydrated during the cooler months.

What is winter dehydration?

‘Training in colder temperatures requires just as much hydration, but people often don’t associate the cold weather with dehydration as much,’ says Rob Hobson, head of nutrition for Healthspan Elite. ‘This is partly because of the brain’s perception of dehydration in the cold, and the fact that cold temperatures cause a decreased perception of thirst,’

Indeed, one study from the University of New Hampshire shows that the loss of fluid from our bodies, which triggers thirst in hot weather, doesn’t elicit the same response when temperatures dip. However, we’re still losing water from our bodies, due to respiratory fluid loss through breathing and sweat that evaporates quickly in cold, dry air.

‘Another factor that can increase dehydration through sweating is overdressing in cold weather, which can increase thermal stress in the body,’ adds Hobson.

Signs you need to drink more water

There’s a long list of things that might happen when you need to drink more. ‘Feeling thirsty is one of the first signs of dehydration, along with dry mouth and lips,’ says Dr Qian Xu, emergency medic and co-founder and medical director of REDjuvenate Medical.

‘If you don’t manage to drink enough water, then your body will try to conserve more water, mainly through the kidneys, so the colour of your urine will go darker, and you will need to go to the toilet less often. As the dehydration becomes more severe, you might start to feel lethargic, dizzy or even confused.’

How much water should I drink every day?

As a general guide, Dr Xu says that 2L of water per day is adequate for most people, but it does depend on weight, activity levels, the temperature of the environment, some medications and caffeine intake. If you’re losing more water than normal, 2L per day might not be enough.

Your body’s water requirement is also weight dependent – an adult needs roughly 30ml per kilogram of weight per day. This means that a 50Kg person would need to drink 1.5L of water per day, while an 80Kg person would need 2.4L of water per day. Don’t forget that many foods, especially fruits and vegetables, contain water, too.

Words: Sarah Sellens | Image: Shutterstock