Here's why experts say you should avoid showering before early morning flights

Here's a hypothetical for you: if you have an early morning flight that involves a 4am alarm, do you wake up to take a shower or just roll out of bed and out the door?If the second one sounds more like your speed, then you're doing things right.At least, that's according to one travel expert who warns holidaymakers that you should never shower before an early morning flight.READ MORE: The best train journeys in the world - and there's an Aussie icon among themNicky Kelvin, editor at travel site The Points Guy, reckons that an early pre-airport shower is just setting yourself up to be more stressed out.Instead, it's better to stay in bed and get a little more sleep.He told Yahoo Life: "Shower the night before, as this will shave 20 minutes off the time taken to get ready, meaning you can have longer in bed."There are some other reasons you might want to consider skipping the shower, regardless of the time of day you're jetting off.Last year, health professional Liberty Mills told the Daily Star that showering before your flight can dehydrate your skin and hair.READ MORE: The best places in the world for island hopping"Showering with hot water and using soap can strip away the natural oils that help keep the skin moisturised," she said."This can lead to dryness and dehydration, which can be exacerbated by the low humidity levels in airplane cabins. The dry air in the cabin can further dehydrate the skin, causing discomfort and potentially leading to issues such as itching or irritation."When it comes to choosing the right time of day to fly, a recent study indicated that those who booked flights in the earlier morning tended to be happier and less stressed.Customer feedback company Happy or Not - who make those smiley face survey terminals you see in airports - revealed that passengers flying around 4am tend to be the happiest. Those flying late at night are often grumpier.READ MORE: The 'aesthetic tray' airport trend you shouldn't be doingBased on responses from seven million customers, surveyed across 30 countries, 85.2 per cent of people tapped the happy smiling face when flying early in the morning.Not only do less travellers in the airport in the early hours mean less stress, but morning flights also tend to be more on time.Booking early morning flights increases the chances of a plane taking off on time by 20 per cent, Scott Keyes, the founder of Going.com told Travel + Leisure.