'I'm a travel expert - there's one thing you need to do on every flight to stay healthy'

If you have a booked, then there is one crucial thing you need to do to make your as painless as possible. Several studies have shown that the air cabin environment can significantly impact fluid balance and retention in the body, with between 1.5 and 2 litres of water lost on average over a ten hour flight.

Matthew Kelly, founder of Spacegoods, has shared his top tips for ensuring you can stay hydrated on - and how to recognise the signs of dehydration before they become dangerous. Fluid loss, especially when essential salts and minerals are also depleted, can lead to dehydration, which may result in nasty side effects such as headaches, motion sickness, fatigue, and dryness of the eyes throat and mouth.

Matthew said: "Most people aim to sleep during a flight to help pass the time, but one of the best ways to stay comfortable, regardless of how narrow your seat is, is by staying hydrated.

"A practical way to do this is to carry a reusable water bottle. Most airlines allow you to bring one onboard, but it must be emptied before passing through security. Fortunately, most airports now provide free water refill stations, enabling you to refill your bottle after security and before boarding your flight."

Another smart way to stay hydrated is with electrolyte powders. Most, if not all powders, contain sodium, potassium, magnesium, and calcium, all of which help regulate fluid balance in your cells.

In the dry cabin environment, plain water may not be sufficient if you're already slightly dehydrated. Electrolytes help your body absorb and retain fluids more efficiently.

Matthew said: "Electrolyte powders, unlike liquids, won't be confiscated at security, making them travel-friendly, as long as they're sealed and meet airline requirements."

Matthew's third tip for making flying slightly more pleasant is face mists.These can bring comfort to dry, tight skin during air travel.

Beauty brands offer travel-sized misters which can fit in your hand luggage, or you can take a small spray bottle, and fill it with water at the airport for your own D-I-Y facial mister.

It's also wise to avoid caffeine and alcohol, as both act as diuretics and increase fluid loss.

If you're on a stag or hen trip and drinking at the airport or onboard, or simply want a drink to ease flying anxiety, balance it out with an equal or greater amount of water to stay hydrated, and try to eat hydrating fruit and vegetables like cucumber, orange or watermelon.