Groggy, grumpy, hangry, short-tempered. You know when you’ve had a bad night’s sleep, as does everybody you come into contact with the following day. Nobody enjoys that sense of lethargy, the irritability, the inability to focus on even the most menial of tasks.

A dearth of good quality sleep can result in inflammation due to raised cortisol levels, weight gain, messed up hormones, impaired cognition and reduced productivity. And - as if that weren’t enough of an incentive to prioritise getting seven to nine hours of shut eye per night - a lack of sleep can seriously harm your immune system.

Clinical studies and Sleep Expert and Director of the Sleep & Health Research Programme at University of Arizona Dr Michael Grandner, have confirmed what we know from our own experience to be true: sound sleep makes for a happier and more productive life, not to mention the noticeable effect sleep has on the way we look.

Scientists are also finding that, in addition to all the other wonderful - indeed, necessary - benefits of sleep, getting those forty winks is fundamental to maintaining a strong and functionally optimal immune system. The reason for this, scientists say, is that sleep augments the ability of T cells to protect against illness and disease.

T cells are a subset of white blood cells that play a central role in the body’s immune response. The cell’s ‘stickiness’ is the key to their ability to fight infection. This ‘stickiness’ refers to literal sticky proteins called ‘integrins’ that are excreted by the T cells when they come into contact with foreign pathogens. The sticky protein enables the T cells to attach themselves to, and kill, infected cells thereby stopping the spread of the virus to other cells in the body.

Clinical studies have compared the volume of integrins excreted by T cells in participants after a solid night’s sleep, and after a broken night’s sleep. Those in the sleep deprivation group produced significantly fewer integrins than those in the high quality sleep group, meaning that their body’s ability to fight infection was markedly reduced in comparison.

Researchers concluded that improved sleep, and the consequent improved levels of integrin activation and thus T cell functioning, has the potential to strengthen the body’s immune response. In people who sleep poorly or suffer from insomnia, immunity may be impaired. Insomnia is particularly common in older people, and women going through menopause.

Further studies have indicated that sub-optimal sleep can put pressure on the endocrine system and interfere with the regulation of stress hormone cortisol. Dysregulation of cortisol, as well as adrenaline and noradrenaline, have been associated with poor sleep quality and can cause the body to enter a chronic inflammatory state as it fights to return to homeostasis. Scientists have known for a long time that the presence of chronic inflammation has a direct association with weakened immunity. This is because chronic inflammation can cause your immune system to go into overdrive. In extreme cases this over-taxing of the immune system can lead to the development of full-blown autoimmune disorders.

The jury is still out on precisely how much sleep we should be aiming for each night - sleep requirements, it seems, are highly individualised - but seven to nine hours is generally agreed upon in the sleep science community as the optimal numbers of hours that an adult should be sleeping each night, and routinely hitting this number should result in improvements in health.

Up to a third of people regularly fail to achieve seven to nine hours of sleep per night which can - in addition to having a negative impact on your immune system - have deleterious effects on everything from mood regulation and insulin resistance to cardiovascular health and both long- and short-term memory. Regularly failing to hit just five hours of sleep per night has been associated with increased mortality.

The bottom line: insufficient slumber can pose a threat to your health over both the long and short term.

Some of the most common factors associated with less-than-optimal sleep include elevated stress levels, over- or under-exercising, over- or under-eating, age (women going through menopause may experience menopause insomnia), eating too close to bedtime, drinking coffee or alcohol too close to bedtime, a bedroom that is either too hot or too cold, a bed that is uncomfortable, or exposure to blue-light emitting devices within an hour before heading up to bed.

Establishing a healthy nighttime routine can be really helpful if you want to improve your sleep. Your routine should avoid the pitfalls mentioned above, and should include any relaxation or wind-down activities that help you to fall asleep. Calm-promoting activities include reading, listening to music, meditating, treating yourself to a bubble bath, or whipping up your favourite snooze-inducing drink.

If you suffer from insomnia and are worried that it’s having a knock-on effect on your immune system, supplementing can help you to fall asleep more easily and stay asleep for longer. LYMA contains two patented ingredients that are clinically proven to improve sleep and reduce sleep onset latency to help feel restored:

Sensoril Ashwagandha is a sleep-supporting powerhouse. The adaptogenic root extract is the highest-concentration extract on the market, is fully patented and confirmed for efficacy, and has been proven in peer-reviewed clinical trials to enhance sleep quality and reduce the time it takes to fall asleep.

affron® is the latest wonder-ingredient to be introduced into the LYMA formula. Six studies to date have demonstrated positive benefits across mood and sleep quality in healthy adults and peer-reviewed evidence has demonstrated affron®’s ability to alleviate insomnia. The active compounds in affron® act on the specific genes, ion channels and neurons that regulate sleep and mood hormones, thereby promoting restorative sleep, and supporting your immune system in the process.

Great quality sleep and a strong and functional immune system go hand in hand, and getting a good night’s sleep can literally help to prevent you from getting sick. If you know that your sleep could be better, longer, deeper or more regular then it’s time to take action. You can’t afford to leave your health to chance.

Always consult your medical professional if you have a medical condition, or existing health protocol, before beginning any new supplementation regime.