The scientific evidence behind sleep supplements
Which herbs and sleep supplements can best help you sleep?
By Laurentia Campbell, Nutritionist and Neuroscientist (mental health, polyphenols, diabetes/obesity, gut microbiota) academic, content writer, food waste warrior & science/healthtech/food/fmcg New Product Devlopment (ideation-scale)
The COVID-19 pandemic and continued remote working (where people sleep where they work), and our ever-increasing addiction to the blue lights on our phones, have interrupted the sleep patterns for many with the National Institute of Health observing a 37% increase in insomnia rates since the pandemic. In a world where medicine has yet to find a long-term solution (as reported in Matthew Walker’s book “Why we Sleep”, most prescription medications cause rebound insomnia) sleep supplements are an expanding market, increasing by 22% since 2018. Evidence for herbal help is growing but be sure to check with a doctor before taking anything new as herbs can interact with current medications. So, what is the scientific evidence behind the claims? What does and does not work?
Melatonin
Melatonin is a hormone produced in the brain by the pineal gland which regulates the body’s circadian rhythm, endocrine secretions, and sleep patterns. Melatonin levels are suppressed by blue light from phones, inadequate sunlight (office jobs and winter- which is why it’s important to get out for a walk in the day in winter or to buy a SAD lamp which replicates sunlight). HRT [2] hormone replacement therapy for menopause (or dysmenorrhea) also suppresses melatonin. Dosages of 2–5g Melatonin have been shown in large scale human randomised controlled (RCT) trials (the gold standard of clinical evidence) to have sleep benefit, especially for those with trouble falling asleep at a conventional bedtime (delayed sleep phase syndrome). In a RCT trial led by professor Wilhelmsen-Langeland at the University of Bergen [3], Norway, it was found that taking melatonin supplements of 1–6mg by mouth shortened the time needed to fall asleep without the hazy hangover the day after left by sleeping pills. This supports the findings in many other trials. You can buy this supplement over the counter in patch or topical form, but these have been shown to have limited benefit in trials. You can also purchase it in Europe or the UK with a prescription. The precursor 5-HTP serotonin, is often used in sleep supplements to help generate melatonin. However, the efficacy of this is less clear. Melatonin can interact with blood thinners, immunosuppressants and some antidepressants, so you should always check with your before taking herbal supplements. The best supplement is Chronobiane 1.9mg melatonin, which can currently be purchased from France online.
Valerian
Valerian is a popular herb which has been used for centuries to help encourage sleep. Found in popular sleep herbal teas such as Pukka nighttime tea and Twining’s sleep tea, it is a popular natural alternative to sleeping tablets. Scientific evidence has shown that taking valerian root extract 300–600mg by mouth daily seems to improve sleep quality, with continuous use for up to 4 weeks suggested before an effect is noticeable. It is frequently found in combination products with other sedative herbs such as hops, passionflower, and lemon balm. Prolonged use may result in dependence, with withdrawal symptoms such as rebound insomnia upon discontinuation and it is advised never to drink alcohol with any sedative herbs. In a systematic review and meta-analysis of 16 RCT with over 1093 human study participants, 8 of which studies were in healthy participants, by Dr Bent at the University of California, it was found that there was a significant improvement in sleep quality as a result of Valerian supplementation [4]. The best Valerian product on the market is Vitabiotics Sleepnight tablets (400mg valerian root extract). Again, make sure you check with your doctor before using herbal medications.
Lavender
Lavender is a herb whose oil (Silexan) is often used in combination with other sleep herbs in doses of 80–160 mg by mouth daily for up to 10 weeks. Lavender essential oil is commonly used in aromatherapy and various topical products such as massage oils and lotions. Although most meta-analyses into the benefits of this herb show no significant difference in study participants for falling asleep, the herb’s relaxation effect was documented in trials, including the metanalysis of 20 RCT by Professor Chen at Sapporo City University, Japan where it was found to increase sleep quality [5].
Passionflower
Like Lavender this herb, also known as Passiflora incarnata, is often used in combination with other herbs and sedatives. It was found in a RCT of 113 healthy men [6] to improve sleep efficiency. Evidence is limited but there are many emerging clinical trials in this area. The best product for this on the market is Holland & Barrett Stress Relief Passionflower 30 Tablets 425mg, which has the required dose, without bulking agents, added sugars, sweeteners, or additives (which impact blood sugar and health).
Chamomile
Chamomile is a popular sleep herb, due to its calming effects [7]. Whilst studies remain uncertain on its effectiveness for promoting sleep, its effects on relaxation and reducing anxiety are well documented. Most current studies are only in animal models and more research is needed. The study by Professor Mousavi at the University of Iran found that chamomile extract significantly improved the sleep quality of elderly people [8]. The best Chamomile products include Pukka nighttime teas with Chamomile, Lemon Balm and Passionflower.
CBD
CBD is the non-psychoactive (it won’t make you high, that’s THC) part of the cannabis plant which has calming properties. What is important is the dosage, with 25–1000mg (ideally 300mg) dosages being found to have best clinical application. Although results are mixed, the 2020 systematic review of 14 preclinical and 12 clinical studies [9] cannabinoid therapies for the management of sleep disorders by Professor Suraev and team at the University of Sydney, found “promising evidence for future randomised controlled trials of cannabinoid therapies in individuals with sleep apnoea, insomnia, post-traumatic stress disorder-related nightmares, restless legs syndrome, rapid eye movement sleep behaviour disorder, and narcolepsy.” The best calming products include those with other sleep promoting agents, such as Trip drinks (with Chamomile, lemon balm, elderflower, and other botanicals) at 15mg CBD and Trip 300mg CBD oils. However, care should be taken as often the strength and source of CBD is unregulated, and so, after first checking with a doctor, start small and self-test your way with products to find what best suits you.
Other options?
- Magnesium
- Lemon balm
- Hops
- Oatflower
- L-theanine
Some people also use Magnesium for sleep, but the evidence for this in large-scale human RCT trials is mixed. This mineral is found in green leafy vegetables, nuts, wholegrains, dairy, soy products (a healthy balanced diet) and some supplements. Lemon balm has been investigated in recent trials and found to have efficacy. The evidence for this is growing. Hops and Oatflower have been researched in human clinical trials and found to potentially have benefits in combination with other sleep aids. L-theanine is another popular option for sleep with research mounting. This comes from caffeinated green tea, so be sure you buy pure form, not caffeinated extract form. Overall watch the conflated claims behind the marketing of sleep aids and always trust the evidence.
Some people also use Magnesium for sleep, but the evidence for this in large-scale human RCT trials is mixed. This mineral is found in green leafy vegetables, nuts, wholegrains, dairy, soy products (a healthy balanced diet) and some supplements. Lemon balm has been investigated in recent trials and found to have efficacy. The evidence for this is growing. Hops and Oatflower have been researched in human clinical trials and found to potentially have benefits in combination with other sleep aids. L-theanine is another popular option for sleep with research mounting. This comes from caffeinated green tea, so be sure you buy pure form, not caffeinated extract form. Overall watch the conflated claims behind the marketing of sleep aids and always trust the evidence.
The verdict?
Overall sleep quality can be improved by watching caffeine content (it has a half-life of 5 hours so don’t drink or eat caffeine (it’s in chocolate, darker chocolate has more) 5 hours before sleep), alcohol and getting exercise and sunlight during the day. Evidence for herbal help is growing but be sure to check with a doctor before taking anything new as herbs can interact with current medications. Be wary of products like Kalms sleep products and Nelsons Rescue Bach Remedy dropper, which make claims about sleep benefits with limited evidence. We can only go on the information we have at any given time, and new scientific research is ever emerging. Follow the most recent evidence from science, from unbiased randomised controlled trials in humans, and let it help take you swiftly to the land of nod.
References
1. Walker, M., Why we sleep: Unlocking the power of sleep and dreams. 2017: Simon and Schuster.
2. Toffol, E., et al., The effect of hormone therapy on serum melatonin concentrations in premenopausal and postmenopausal women: a randomized, double-blind, placebo-controlled study. Maturitas, 2014. 77(4): p. 361–9.
3. Wilhelmsen-Langeland, A., et al., A randomized controlled trial with bright light and melatonin for the treatment of delayed sleep phase disorder: effects on subjective and objective sleepiness and cognitive function. J Biol Rhythms, 2013. 28(5): p. 306–21.
4. Bent, S., et al., Valerian for sleep: a systematic review and meta-analysis. Am J Med, 2006. 119(12): p. 1005–12.
5. C1.Y., et al., The Effect of Lavender on Sleep Quality in Individuals Without Insomnia: A Systematic Review. Holist Nurs Pract, 2022. 36(4): p. 223–231.
6. Lee, J., et al., Effects of Passiflora incarnata Linnaeus on polysomnographic sleep parameters in subjects with insomnia disorder: a double-blind randomized placebo-controlled study. Int Clin Psychopharmacol, 2020. 35(1): p. 29–35.
7. Srivastava, J.K., E. Shankar, and S. Gupta, Chamomile: A herbal medicine of the past with bright future. Mol Med Rep, 2010. 3(6): p. 895–901.
8. Adib-Hajbaghery, M. and S.N. Mousavi, The effects of chamomile extract on sleep quality among elderly people: A clinical trial. Complement Ther Med, 2017. 35: p. 109–114.
9. Suraev, A.S., et al., Cannabinoid therapies in the management of sleep disorders: A systematic review of preclinical and clinical studies. Sleep Med Rev, 2020. 53: p. 101339.
