The morning of Sunday 27 October will be dominated by a flurry of collective research into whether the iPhone automatically adjusts to daylight saving time. After this, there’ll be the inevitable fiddling with all the buttons in our cars in the hope that one of them controls the clock. So why don’t we also ensure that our circadian rhythm – the internal body clock that tells the body when to sleep, rise and eat – has also adjusted to this shift? Seasonal Affective Disorder (SAD) is proof of just how much difference one hour can make.

Many studies have attributed SAD to individuals being so sensitive to the decrease in sunlight during winter that their circadian rhythm is thrown off balance. This can lead to an increase in production of the sleep-inducing hormone melatonin, which can lead to drowsiness, constant fatigue and the craving of starchy and sugary carbs. Darker days also reduces the production of serotonin – the happy hormone that thrives on sunlight and vitamin D – and so those with SAD often struggle with symptoms similar to ones associated with depression.

Try… People who think they may suffer from SAD will benefit from getting outside as much as possible in order to boost depleted vitamin D levels. Can’t bank on the sunshine? Light therapy boxes mimic sunlight and have been shown to suppress the excess production of melatonin, as well as alleviating symptoms of SAD. It also pays to think about your food as eggs and oily fish such as wild salmon are great nutritional sources of vitamin D. Meanwhile turkey and bananas are rich in the amino acid tryptophan, which converts into serotonin in the body. This daylight saving time, forget about checking in on Siri – go make yourself a big, fat, turkey and egg sandwich.