Can't sleep? A cup of one particular herbal tea could help, says research

Insomnia's no joke, and if you're reading this through bleary eyes after yet another tiresome night of not enough sleep, you're doubtless keen to learn of anything that can help you get a blissful, uninterrupted eight hours or even more. 

You might have invested in the the best mattress to no avail, and maybe even the best pillow to go with it, and if sleep's still not happening for you then you might even have tried the best sleep tracker to get to the bottom of your insomnia. However it turns out that what you might really need to do is go old-school if you want to improve your prospects of a good night's sleep.

The passion flower (specifically Passiflora incarnata Linnaeus) has a longstanding reputation as a natural medicine, and it's been used around the world to treat anxiety and menopausal symptoms, and it's also been used as an anti-asthmatic and analgesic treatment. However it's also a popular insomnia treatment, and modern research has found that it's more than an old wives' tale; there's now some serious scientific evidence to back it up.

Most recently a study at the Soonchunhyang University College of Medicine in South Korea found that in subjects with insomnia, taking a passion flower extract significantly improved sleep prospects. 110 people took part in the study, and were given either a passion flower extract or a placebo for two weeks. They underwent polysomnography to record sleep activity, as well as completing sleep diaries.

At the end of the study, it emerged that the subjects given the passion flower extract showed greatly improved sleep time, while the placebo group showed no change. And there were similar improvements in sleep efficiency and wake after sleep onset (the amount of time you stay awake after a sleep cycle), too.

This isn't the first time that science has backed up the passion flower's sleep-assisting powers, either. Another study in 2011, on a group of 41 participants, also found that passion flower tea resulted in much-improved sleep quality after just a week.

So if sleep's not happening for you, try a soothing cup of passion flower tea at bedtime. And maybe you could make a little bedtime snack of one of these 10 foods recommended by a sleep expert, too.

• 3 sleep aids that actually work, according to a sleep expert
• QuietOn 3 sleep earbuds review: a silent dream for side sleepers