Scientists have found out that drinking coffee close to bed time may not stop you getting off to sleep after all, a study suggests. Instead it is alcohol which is far more likely to lead to a night of tossing and turning.
Researchers track the sleep of nearly 800 people over 6 nights and asked them to note if they have consumed caffeine, alcohol or nicotine in the four hours before bed. Almost half had caffeinated drinks at night, but no link with poor sleep could be found.
In contrast, those who drank alcohol saw their sleep efficiency fall by almost 1 percent – the equivalent of five minutes lost sleep.
Those who smoke before bed saw a 2 percent fall in their sleep efficiency, an average of 8 extra minutes awake.
The study, published in the Journal of Sleep, did not take into account how much caffeine the participants drank or how sensitive they were to it. Some people break it down in their bodies faster than others.
Lead author Dr Christine Spadola of Florida Atlantic University said, ‘while we did find that evening consumption of alcohol and nicotine were associated with sleep disruption, we did not find an association between consumption of caffeine within four hours of bedtime and sleep disruption.
‘This was a surprise to us but is not unprecedented – the previous evidence is mixed when it comes to the effect of caffeine on sleep.
‘However, it is important to note that we did not look at caffeine dosing or individual tolerance and sensitivity levels, which are important factors that can impact the effect of caffeine on one’s sleep. Over all, it is best to limit caffeinated drinks after 12 noon for optimal sleep’.
Alcohol affects chemicals in the brain and is known to cause shallower sleep. Caffeine and nicotine are stimulants which can block chemicals important for sleep.
The NHS advises people looking for a better night’s sleep to cut down on caffeine in coffee, tea, energy drinks and colas, especially in the evening. It recommends a warm milky drink or herbal tea instead.
All the above makes a great deal of sense. Coffee in moderation has for me a great deal of benefit as far as my digestive system is concerned and an occasional alcoholic drink during the day especially with a good lunch at my favourite restaurant Le Boudin Blanc in Shepherd Market seems to trigger off my writing ability. Thank God for that.