Insomnia is a common problem for adults, with at least one
third of adults worldwide experiencing symptoms. Over the counter sleep
supplements promise a deep refreshing sleep. Does the evidence support these
claims?
Most OTC supplements are a mixture of herbs
A browse along your pharmacy shelf will reveal a plethora of
sleep supplements available to buy without a prescription. The labels boast a
variety of specific benefits including “beauty sleep” “deep sleep” “fall
asleep” “sleep recovery”. However if you read the ingredients labels, most of
these preparations contain a mixture of similar herbs.
Common herbal preparations in sleep supplements include:
valerian, kava, wuling, hops, chamomile, passionflower and St. John’s wort.
Most claims are not backed up by science
Very few scientific studies have examined the effectiveness
of these herbal ingredients. The studies that have been done focus on a
specific herb rather than the combination you will find in a supplement.
Overall, the evidence that herbal supplements will actually help you sleep is
“low” (stronger ratings would be “moderate” or “high”). There is, however, some
promising research that three herbs may help reduce anxiety: kava,
passionflower and chamomile. Anxiety often contributes to poor sleep so these may
be of some benefit.
Magnesium supplements
In the last year, there has been an explosion in the
availability of supplements containing magnesium for sleep. Although magnesium
is crucial for muscle and nerve function, the studies report only a minimal
impact, if any, on sleep. A healthy balanced diet will provide you with the
recommended amount of magnesium and adding more is unlikely to be helpful. If
your diet is lacking vegetables and wholegrains then perhaps a magnesium
supplement would be beneficial. Remember it is always better to obtain vitamins
and minerals from food rather than a tablet.
Melatonin
Melatonin is not a herbal preparation. It is a natural
hormone produced by the brain that signals it is time to go to sleep. Levels of
melatonin increase at night, hence it is often referred to as the hormone of
darkness. Melatonin is useful for treating jet lag and specific sleep
syndromes.
Depending on your country, melatonin may be able to be purchased
over the counter as a supplement rather than as a pharmaceutical drug. These
supplements are available without a prescription, but they contain such a small
amount of melatonin they are very unlikely to help you sleep. It is important
to understand that the over the counter preparations are not considered “drugs”
and are therefore not subject to the same rigorous testing for quality and
effectiveness that prescription medications undergo.
In some countries, melatonin tablets are available by
prescriptions to treat certain sleep disorders and depending on your location,
may be available for people aged over 55 without a prescription. You should
discuss with your pharmacist and doctor if melatonin is likely to help you as
for many individuals it will not be effective. Focusing on lifestyle changes
can often have a more significant impact on your sleep.
Can sleep supplements be harmful?
Herbal supplements are not tested for safety. There have
been reports of serious liver disease from the use of kava while hops are known
to cause skin rashes and changes to the menstrual cycle. High doses of
magnesium are likely to cause gut side effects and may be dangerous. You should
always be cautious with any over the counter product – we often mistakenly
think they are safer because they are natural or herbal. They can also
interfere with any other medications you may be taking, so be sure to ask your
GP before starting to take a supplement.
Understand the real reason you cannot sleep
The first step to improving your sleep is to complete a
sleep diary. These are freely available on the internet. Complete the diary for
one week. You will observe connections between things you do during the day and
the quality of your sleep. For example, it took you a long time to fall asleep
when you spent several hours scrolling on your phone in bed; or you had a good
sleep on the night you did yoga after work. Noticing will allow you to make
specific changes to your daily routine.
