Research from the Centre for Nutrition, Exercise and Metabolism at the University of Bath (UK) looked at the combined effects of caffeine and disrupted sleep on our metabolism and found surprising results. They found that a strong, black cup of coffee to wake you up following a bad night’s sleep might impair control of blood sugar levels.
The team showed that while one night of poor sleep has limited impact on a person’s metabolism, drinking coffee to perk up from a slumber can have a negative effect on blood sugar control. Due to the importance of keeping our blood sugar levels in a safe range to reduce the risk of conditions such as heart disease and diabetes, the team’s results could have far reaching implications on health. This is especially important considering the worldwide popularity of coffee.
For the study the physiologists at the University of Bath had 29 healthy women and men undergo three different overnight experiments which were in a random order. In one, these participants had a normal night’s sleep and were then asked to consume a sugary beverage on waking in the morning.
In another experiment, the participants experienced a disrupted night’s sleep (the researchers woke them up every hour for a five minute period), and then on waking were given the identical sugary beverage as the first group.
For the third experiment, the participants experienced the same disrupted sleep as the second group but in this group they were given a strong, black cup of coffee 30 minutes prior to drinking the sugary beverage.
Blood samples were taken from all participants in each of the tests. They were taken after consuming the sugary beverage which in energy calories mirrored what might typically be consumed for breakfast.
The team’s findings highlight that one night of disrupted sleep did not result in any worsening of the participant’s blood glucose/insulin responses at breakfast when compared to a normal night’s sleep. Earlier research has suggested that losing many hours of sleep over one night and/or multiple nights might have negative effects on metabolism. Based on the new research, a single night of fragmented sleep which could be due to noise disturbance, insomnia or other disruptions, does not have the same effect.
However, a cup of strong, black coffee before breakfast substantially increased the blood glucose response to breakfast by about 50%. Population based surveys have indicated that coffee may be associated with good health although past research has demonstrated that caffeine has the ability to cause insulin resistance.
The new study reveals that the remedy of consuming coffee following a bad night’s sleep may solve the problem of feeling sleepy, however could lead to limiting the body’s ability to tolerate sugar consumed with breakfast.
The team notes that nearly half of us will wake up in the morning and prior to doing anything else will reach for a cup of coffee. Intuitively, the more tired we are the stronger the coffee we will consume. This new study is important and shows far reaching health implications as until now we have had limited knowledge in regards to what this may be doing to our bodies and in particular to our blood sugar and metabolic control.
The study shows that consuming coffee first thing in the morning and particularly after a bad night’s sleep, impairs our blood sugar control. We may be able to improve this by eating breakfast first and consuming coffee later if we feel we need it.
The results have indicated that one night of disrupted sleep did not worsen the participant’s blood glucose/insulin response to the sugary beverage compared to a normal night’s sleep which can be reassuring to many of us. However, beginning the day following a poor night’s sleep with a strong cup of coffee did have a negative effect of about 50% on glucose metabolism.
People should try to balance the potentially stimulating benefits of caffeinated coffee in the morning with the potentially higher blood glucose levels. It may be better to drink coffee after breakfast rather than before.
There is still a lot more to be learned about the effects of sleep on our metabolism. Questions remain as to how much sleep disruption is required to impair our metabolism and what longer term implications of this might be. Also, can exercise for instance help to counter some of this.
To view the original scientific study click below