I had a press release the other day from the PR people of a department store here in the UK telling me that sales of sunlight simulating lamps are up 80 per cent on last year. The proposed explanation but this surge in sales has been the dismal, largely sunless summer we’ve had in the UK. The press release was well timely, seeing as literally two days before I’d cracked out the sunlight-simulation lamp I bought last year in an effort to combat any negative effects from the dismal weather which is only set to get more dismal as we approach autumn and winter.
Such devices are generally marketed as a solution to season affective disorder (SAD), characterised by low mood/depression in the winter months. Other symptoms that may come with this condition including fatigue and cravings for carbohydrate. However, there is at least some evidence which suggests that taking steps to ensure decent sunlight (or equivalent) exposure during the winter might have real benefits for individuals who are not suffering from the symptoms of SAD. It is possible, or course, that lack of sunlight may lead to changes that are not severe enough to be labelled as ‘SAD’, but nonetheless may have adverse effects on wellbeing.
This idea was tested in a piece of Finnish research published in the year 2000. Here, light therapy was administered to office workers, some of whom had symptoms of SAD, and some of whom did not. Office workers are a good population to study in this sort of experiment because they can be prone to lack of sunlight in the winter, by virtue of the fact that they can find themselves going to and from the office in the dark, and may perhaps get stuck in the office at lunchtime too. It is feasible, therefore, for office workers to get very little sunlight exposure through the working week.
As expected, light therapy was found in this study to improve SAD symptoms. However, it also seemed to benefit ‘healthy’ individuals who were not sufferers of SAD in terms of vitality and mood. This study was hampered by relying on self-reporting of symptoms, whereas more formal assessment of symptoms might have given a more accurate picture of any benefits. However, if lack of sunlight can cause depression, logic dictates it may also cause more subtle health and wellbeing issues that might respond to increased exposure to light therapy or sunlight. It might also be that light may enhance mood and wellbeing in individuals who are not necessarily suffering from a ‘lack’ of sunlight, as such.
My belief is that many of us can benefit from being mindful of the need for sunlight exposure during the darker months. For office this workers, this may mean making an effort to get out at lunchtime. If this can be coupled with some exercise such as walking, even better, as exercise has been shown to help improve symptoms of SAD too. This might be fine on a crisp, sunny day in the winter, but is simply not practical for most people when its bucketing down with rain or the ground is covered in snow.
For these reasons, I do see sunlight simulating lamps are worth considering. Small, portable units are now available that can deliver a good dose on light in as little as 10 or 20 minutes. Using one may well ensure that the winter months do not seem as bleak as they might otherwise be.
Partonen T, et al. Bright light improves vitality and alleviates distress in healthy people. J Affect Disord. 2000;57:55-61.