If you're feeling bleary-eyed today after a less-than-satisfactory sleep, you're not alone in your predicament. One in four people suffers from insomnia every night and the root cause is usually stress, according to a study by Stanford University in California.

The study also shows that women seem to be more sleep-deprived than their male counterparts. Some 27% of women surveyed said they wake every night compared to 19% of men.

Without a good night's snooze, you're more likely to under-perform at work, forget simple tasks and have mood swings during the day.

To make sure you drift away to the land of nod, follow our top tips.

Eat the right foods

If you've skipped a meal during the day, you might end up missing some sleep. Not eating enough calories can cause the neurotransmitters in the brain that control hunger to go into overdrive so you won't be relaxed enough to sleep.

Make sure you eat early in the evening and try to chomp on foods that contain melatonin, a substance that helps regulate your body clock. Oats, sweetcorn and rice are the best sources of melatonin.

Sleep separately |from your partner

This may be difficult if you like nothing better than snuggling up next to your other half. A study by the University of Vienna showed that both genders have a more disturbed sleep when they nod off with their partner.

Women seem to fare better than men when they share their bed because they tend to sleep more deeply. However, men seem to suffer temporary blips in their brain power the day after sharing a bed — no doubt due to their disturbed sleep!

The obvious answer to this one is to swap your double bed for twin beds, but, as a compromise, you could consider getting a bigger bed and making sure you have plenty of bedclothes.

Switch off your worries

One of the most common complaints from insomniacs is that they can't stop thinking about family worries, financial fears and problems at work.

Some people have lost the ability to relax their mind. Cognitive behaviour therapy can help some people to relearn their thought patterns and manage to turn off that worry switch.

Try Tai Chi

Researchers at UCLA have found that practising Tai Chi can help people sleep better at night. Nearly two-thirds of the people in a study who learnt a westernised version of the ancient Chinese martial art had significant improvements in their sleep quality.

Give your bed an MOT

You give your car the once over and go for a medical check-up, so why not take the time to evaluate how your bed is functioning? Sleep expert Dr Chris Idzikowski carried out a study in 1988 that found that swapping an uncomfortable bed for a comfy, new one could account for an average of 42 minutes' extra sleep.

You can give your bed an MOT courtesy of the UK's Sleep Council (www.sleepcouncil.com). Among the crucial questions are whether your bed is more than 10 years old and if you ever wake up with neck or back ache.

Sleep only at night

While research has shown that there are some health benefits to taking a siesta (there is a study linking it with a lower risk of dying from heart disease), it would be a big change for us to adopt a three-hour sleep in the middle of the day.

One problem with taking short naps during the day is that it can sometimes cause difficulty getting to sleep in the evening.

Keep active

Exercising too late in the day may stop you getting a good night's sleep, because your body and mind will be over-stimulated. But you should make sure you get plenty of physical activity earlier in the day.

A study by the Stanford University Medical School showed that older and middle-aged people reported that they slept better after they added regular exercise to their routine. It took 16 weeks for the benefits of the moderate-intensity exercise to be seen, but, by this stage, they were able to fall asleep about 15 minutes earlier and sleep about 45 minutes longer at night.

Keep your bedroom |as dark as possible

Make sure you close your curtains completely and turn off any devices that have a light (such as phone chargers or your TV standby light).

If there's light in the room, it can disturb your circadian rhythm and fool your body into thinking it's time to be awake.

Regulate the temperature

One of the most common causes of a restless night is sleeping in a room that's either too hot or too cold. But, strangely, wearing socks to bed can actually help you drift off, particularly if you're a woman.

"Women who wear socks in bed fall asleep 27% faster than those who go barefoot as the increase in temperature sends a signal to your brain to snooze," say researchers at the Netherlands Institute for Brain Research.

Try not to obsess |about sleep

When you can't snooze at night, the temptation is to stay in bed and fret about it. Sleep expert Professor Kevin Morgan says this tactic is self-defeating.

"Sleep is a completely automatic activity and trying too hard to get to sleep will not help it happen," he says.

To help you chill out, remove your clock from view as staring at the time will only add to your anxiety.