Creams and lotions can be very helpful for keeping the skin soft and smooth, but beauty sleep is just as important — if not more so. Studies are showing that this old adage is grounded firmly in science, not mythology. They reveal that getting sufficient slumber helps keep your skin looking radiant, makes you less stressed, keeps weight off and, to boot, keeps your endocrine and cardiovascular systems healthy.

Hormones are deeply linked to both health and beauty, from acne to skin plumpness, weight loss and hydration — think how hormones can wreak havoc on skin in the teenage years. Then there’s the love/hate relationship with oestrogen for women: while it helps keep the skin plump and hydrated when we are younger, it also may be the driving force behind the rippled skin effect of cellulite and, as we age and its levels decrease, so does skin moisture.

There are, however, many types of hormones aside from those of the sexes that can have a spectacular impact on our skin and health. When we sleep, powerful but good hormones such as melatonin and human growth hormone are secreted. Of course, the release of these natural skin and health elixirs is dependent on good-quality deep sleep, not merely superficial or stressed sleep.

Melatonin is essential to healthy sleep patterns. It acts as a powerful antioxidant in the body by increasing the activity of the main antioxidant enzymes and other chemicals that protect cells against free radical damage. It therefore helps protect the body’s cells (including skin cells) against the harmful effects of ultraviolet damage, pollution and stress.

Then there’s human growth hormone, released when we slumber well. HGH is necessary for helping to build and repair body tissues such as muscle and bone and, of course, skin-dependent collagen. It also helps to combat the negative effects of cortisol, the stress hormone.

Cortisol is a powerful hormone we can do with less of: while it is helpful for the short-term fight-or-flight response, when sustained it can wreak havoc on all the body’s systems and contributes to many diseases. A bad night’s sleep increases the production of this pesky hormone, which can last all day. Cortisol blocks the formation of collagen, the main protein that provides the network of support for your skin, making it firm, bouncy and resilient. High levels of cortisol have an adverse affect on the immune cells in the skin’s epidermis, disrupting the skin barrier and weakening the skin’s defence against UV light, infections, pollutions and other environmental stress. It also may well trigger or play a part in the severity of eczema and dermatitis.

Additionally, these high levels of stress are purported to trigger the release of brain chemicals called neuropeptides, known as Substance P, that can trigger the production of more sebum and inflammatory chemicals called cytokines, both of which can lead to acne. So the key is to get more melatonin and human growth hormone and less cortisol. And the simple answer is not an expensive treatment, but good-quality sleep.

So, where possible, relax and before you spend your money on an expensive night cream or a visit to a beautician, you may want to invest in some relaxing nights in. In saying that, night time is the perfect time to reap the benefits of skincare. Research suggests there is an acceleration of skin cell production at night, making it the ideal time for the body to rest and the skin to absorb moisture and nutrients. The temperature of the body is higher, too, increasing oxygen-carrying blood to the skin, giving us that lovely fresh glow on waking.