Most people understand the importance of good quality sleep for mental and physical health. As the NHS explains, the mental health benefits associated with good sleep include reduced stress and improved mood. Sleep also supports important bodily functions and boosts the immune system.

Yet, it can sometimes feel like getting a good night's sleep is easier said than done. For some people struggling with poor sleep, diet could be the cause. For instance, people who drink caffeine might find that it affects their sleep.

According to the NHS: "Caffeine is a stimulant which means it makes you feel more awake. But it can also disrupt your usual sleep rhythms, leading to problems sleeping and then daytime tiredness." Caffeine is often found in coffee, tea, fizzy drinks, and energy drinks.

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Given that the effects of caffeine can last for up to seven hours, the NHS says it's generally best avoided in the evenings if you struggle with your sleep. Some people might choose to avoid it in the afternoons, too.

The experts at the Royal College of Psychiatrists recommend following a '2pm rule' to improve sleep quality. Advice on the website explains: "Stop drinking tea, coffee or anything else with caffeine in it by 2pm. If you want a hot drink in the evening, try something milky or herbal and caffeine-free."

To improve sleep, the Royal College of Psychiatrists also suggests that people follow a regular sleeping and waking routine and follow a wind-down routine before bed.

The advice states: "It is normal for our minds to become very busy when we get into bed. For many of us it's the first time all day that we can be alone with our thoughts. So it's not surprising that our brains become very active when we get into bed and turn out the lights.

"To stop this from happening, set aside 30 minutes to a couple of hours before you go to bed where you don't work, study or do things that cause you to think a lot. Use this time to relax and wind down, and to finish processing your thoughts about what happened during the day. If possible, leave your phone outside your room before you go to bed."

According to the experts, other helpful strategies include taking a warm shower before bed and writing down any worries or tasks that need completing the next day so that you can forget about them.

Sleep problems can usually be resolved with improved sleep habits; however, it's advised to speak to a GP if you have any health concerns. The NHS says to see a GP if you have had trouble sleeping for months, changing your habits has not helped, or if insomnia is affecting your daily life.