…Because every image of insomnia freely available online is indistinguishable from a staring competition
A friend recently brought my attention to the latest Lush product which had literally been “blowing up her Instagram”. After seeing news articles such as this, I wanted to find out whether the evidence supported the hype. Now, before I start, I want to say that I have absolutely no problem with people paying for what they feel helps them. If you suffer from insomnia and find that this product helps you where other products have not then please keep using it. However, I want to draw attention to the tenuous support for its active ingredients and the fact that most people would benefit just as much from taking a hot bath and introducing a bunch of flowers into their bedroom. At a sell-out price of £13.95 for 215g it strikes me there should be some strong evidence to back up its miraculous effects.
So, what is the evidence for the soporific effects of Lush’s latest goop? Well, the website argues that because the cream contains lavender and oatmeal that this should help individuals drift off to sleep. To quote the Lush website, “You’ll sleep well after dipping into this dreamy lotion, made with a gentle oatmeal infusion, calming lavender flower and comfortingly sweet tonka absolute.” According to the reviews on the website, and social media, this seems to be the case. The main reason for this appears to be the relaxing and anti-anxiety properties of the cream which plenty of customers are swearing by. However, what is the research evidence that this expensive cream does what it says on the tin?
Let’s assess the key ingredient, lavender. I have chosen to focus on lavender as this is the only active ingredient I could find which had any research linked to sleep (apparently tonka beans and oatmeal are great to eat though). Lavender oil has been championed as a natural way to improve sleep in healthy individuals and those suffering from insomnia. There are numerous blogs which support its use and there is even a brief reference to it on NHS resources for insomnia. Nonetheless, neither of these prove that lavender oil has a genuine impact on sleep beyond a placebo effect. It may be that the expectation that lavender will improve sleep or increase relaxation is responsible for its positive effect.
This exact point was shown clearly in a study conducted almost ten years ago by Siobhan Howard & Brian Hughes in the British Journal of Health Psychology. They found that it was the expectation of an effect, and not the lavender aroma itself, which was responsible for the calming effects it produced. They asked participants to smell either a jar of lavender oil or a jar full of a control aroma (tea tree). Following this, their levels of relaxation (measured objectively using galvanic skin response) and self-reported anxiety were assessed. The researchers found no effect of lavender oil on either of these measures. However, when participants were told that the oil would enhance relaxation, as compared to decrease it, they found that objective relaxation levels increased. The opposite was found when participants were told the lavender would decrease their relaxation levels. This effect was not found for the self-report measure of anxiety. This suggests that simply being told lavender oil is relaxing or not is enough to produce a physiological relaxation response.
Admittedly, this is one study. So what does the wider pool of research suggest? Well typically we can go to a systematic review to see a summary of all of the research in an area but there are few reviews assessing lavender and sleep. There are a couple on aromatherapy and complimentary medicine’s effect on sleep but these include a small number of, or no, studies examining lavender oil. So, like any good scientist, I decided to conduct a quick systematic review myself. This was done in a shorter time than you would do a typical review so please tell me if I’ve missed anything critical (*I can provide anyone with the documents and stages of my systematic review so you can work through them if you’re super interested or are keen to prove me wrong). However, I’m guessing most of you just want to hear whether the research supports the use of lavender, right? Does the research support its widespread use? Well the short answer is no, not especially. The longer answer is that the evidence conducted in this area is largely poor and very little has been done in healthy individuals in a non-clinical setting so it is hard to ascertain whether there is a true effect here. What were the main problems with these studies? Well, most of these studies did not adequately control for the problematic issue of placebo effects. A failure to account for this by not including an active control (e.g. a control which is comparable to the treatment) can inflate the effects of any potential intervention. This is dishonest as it creates an biased view of how successful a specific drug or therapy is compared to the effect of expectation that a therapy will work. It’s admittedly not that unusual in drug trials (see everything by Ben Goldacre) but it is important to understand if you want to know whether you haven’t just got an expensive placebo in front of you. Placebo effects can produce meaningful changes to health but it is much cheaper to take a sugar pill than an expensive therapy and it is important to be aware of this in healthcare.
When bees need sleep they make sure to cover themselves in lavender petals before settling into bed with Netflix
The importance of considering placebo effects was highlighted clearly in one study identified via my search. On first glance, it appeared that smelling lavender oil over 8 weeks had a big impact on perceived sleep quality (a 40% improvement in sleep from the initial baseline). Pretty good, huh? Well, when the researcher analysed the findings from the placebo condition (e.g. smelling distilled water, not a perfect control but better than nothing), they found a 27% improvement in sleep scores from the initial baseline. This means that, accounting for placebo effects, a 13% improvement in sleep, over 8 weeks, was found after smelling lavender oil for an hour before bed. This is admittedly still bigger than 0 but the improvement of 13% is fairly negligible for participants who were already sleeping well in this experiment. One study did conduct their experiment on self-reported poor sleepers but found no effect of lavender oil on any individual sleep diary measurements. When sleep was assessed using an established sleep questionnaire (the Pittsburgh Sleep Quality Index) they did find a significant improvement in sleep quality for participants wearing a patch containing lavender oil compared to a control (an identical patch contained nothing). This suggests that lavender oil delivered as a patch may improve sleep in college students. However, it is hard to say whether expectancy effects played a part here as despite the claim that the participant and experimenter didn’t know which patch they received, the absence of oil in one and presence in another is something I’m not convinced a participant wouldn’t notice. Happy to be argued against.
The only other study conducted on healthy young adults was carried out by Goel and colleagues in 2005. They found that lavender oil (compared to odourless water vapour) produced a small increase in deep sleep for the first half of the night. This is interesting as deep, or slow wave, sleep is important for a number of different cognitive functions including memory. By including this study, that produces the grand total of 3 research papers which assessed the effect of lavender oil in a sample equivalent to the claims made by Lush. The other studies included those in an intensive care unit (ICU) following surgery, elderly individuals suffering from dementia, participants with chronic liver failure, postnatal mothers, those with major depressive disorder, and those in the ICU for an undisclosed reason. I’m not saying we can’t learn anything about the effect of lavender oil on sleep from these samples but they are considerably different in the reasons for their sleeplessness. A busy and stressful ICU ward is a different environment than say a bedroom in your own home. Nonetheless, I’ve included all of the other studies in a table for your perusal below so you can make up your own mind on whether I should talk about these more (these are even less conclusive than the studies I’ve talked about above).
So why might we see a positive effect of lavender infused cream on sleep if there is such weak evidence to support its use? Well, one clear contender which I’ve harped on about is the placebo effect. I’m sure I will receive plenty of flak for this but it has been consistently shown that placebos, even if we know they are placebos, can produce dramatic results on our health. In respect to sleep, simply being told you are sleeping better (even if this is objectively false) can produce an increase in functioning. I don’t doubt or question the effect of a powerful placebo and I have no problem with people using things which help a problem they have considered previously intractable. What I do have a problem with is people paying £13.95, or more, for a product which is no more effective than a warm bath and good sleep hygiene. This is an issue hardly confined to Lush or their products. I am sure there are many spending much more on other products in the hope of finding a solution for their insomnia.
So, what do I recommend instead of paying for expensive goop and smothering it over yourself on a nightly basis? I mean, surely, I should put forward a counter suggestion if I am going to claim ‘Sleepy’ isn’t based on sufficient evidence to support its claims. Well, firstly, if you are suffering from insomnia then go to see your GP in the first instance and consult resources created by clinical and academic experts in insomnia. These should be your first port of call and both will provide scientifically proven advice on how best to manage your sleeplessness. If products such as ‘Sleepy’ work wonders for you and you’re happy to pay for them then ignore me – I promise I won’t be offended. However, try to incorporate your own relaxation methods into your bedtime schedule and see whether these can replace ‘Sleepy’. If they don’t then go back to scented creams safe in the knowledge you’ve proven me wrong. However, if they do then do yourself a favour and save yourself the time and money which Lush’s product requires.
Alternatively, Lush could provide me with enough free cream to run a large randomised controlled trial of this stuff. Just sayin’.
*If you want more information about the systematic review leave a message below and I’ll happily email you the documents.
Systematic review of lavender on sleep (Excel spreadsheet with results for review – includes demographics and quick quality assessment)
Goel, N., Kim, H., & Lao, R. P. (2005). An olfactory stimulus modifies nighttime sleep in young men and women. Chronobiology international, 22(5), 889-904.
Howard, S., & Hughes, B. M. (2008). Expectancies, not aroma, explain impact of lavender aromatherapy on psychophysiological indices of relaxation in young healthy women. British journal of health psychology, 13(4), 603-617.
Lillehei, A. S., Halcón, L., Gross, C. R., Savik, K., & Reis, R. (2016). Well-Being and Self-Assessment of Change: Secondary Analysis of an RCT That Demonstrated Benefit of Inhaled Lavender and Sleep Hygiene in College Students with Sleep Problems. Explore: The Journal of Science and Healing, 12(6), 427-435.
Kamalifard, M., Farshbaf Khalili, A., Namadian, M., Ranjbar, Y., & Herizchi, S. (2017). Comparison of the effect of lavender and bitter orange on sleep quality in postmenopausal women: a triple-blind, randomized, controlled clinical trial. Women & Health, (just-accepted).
** (Read this and then read Bad Science if you’re interested in placebo effects and how science can be spun to support absolute rubbish) Goldacre, B. (2012). Bad pharma: how medicine is broken, and how we can fix it. HarperCollins UK.
** (Great page from the NHS which summarises my points on why we need to be concerned about what is placebo and what is not in healthcare) http://www.nhs.uk/Livewell/complementary-alternative-medicine/Pages/placebo-effect.aspx