Drinking coffee before breakfast may worsen blood sugar

October 6, 2020 in Diabetes & Diabetes Prevention, Nutrition Topics in the News

Drinking coffee before breakfast may worsen blood sugar

A strong, black coffee to wake you up after a bad night's sleep could impair control of blood sugar levels, according to a new study.

For the small study, researchers from the University of Bath (United Kingdom) looked at the effect of broken sleep and morning coffee on a range of different metabolic markers.

The scientists show that while one night of poor sleep has limited impact on our metabolism, drinking coffee as a way to perk you up from sleep can have a negative effect on blood sugar control.

The researchers asked 29 healthy men and women to undergo three different overnight experiments in a random order:

·        In one, condition participants had a normal night's sleep and were asked to consume a sugary drink on waking in the morning.

·        On another occasion, participants experienced a disrupted night's sleep (where the researchers woke them every hour for five minutes) and then upon waking were given the same sugary drink.

·        On another, participants experienced the same sleep disruption but this time were first given a strong black coffee 30 minutes before consuming the sugary drink.

In each of these tests, blood samples from participants were taken following the sugary drink which had a calorie content of what might typically be consumed for breakfast.

Coffee before breakfast boosts blood glucose response to breakfast

One night of disrupted sleep did not worsen participants' blood glucose / insulin responses at breakfast, when compared to a normal night's sleep. Past research has suggested that losing many hours of sleep over one or multiple nights can have negative metabolic effects.

However, strong black coffee consumed before g breakfast substantially increased the blood glucose response to breakfast by around 50%. While many studies have linked coffee to good health, some research has demonstrated that caffeine can cause insulin resistance.

The lead researcher explains: "We know that nearly half of us will wake in the morning and, before doing anything else, drink coffee - intuitively the more tired we feel, the stronger the coffee. This study has health implications as up until now we have had limited knowledge about what this is doing to our bodies, in particular for our metabolic and blood sugar control.”

Consider drinking coffee after breakfast versus before

These results showed that one night of disrupted sleep alone did not worsen participants' blood glucose/insulin response to the sugary drink compared to a normal night of sleep. However, starting the day after a poor night's sleep with a strong coffee did have a negative effect on glucose.

The researchers recommended that people should try to offset caffeine’s potential for higher blood glucose levels by having coffee after breakfast rather than before.

Source: British Journal of Nutrition, September 10, 2020.

All research on this web site is the property of Leslie Beck Nutrition Consulting Inc. and is protected by copyright. Keep in mind that research on these matters continues daily and is subject to change. The information presented is not intended as a substitute for medical treatment. It is intended to provide ongoing support of your healthy lifestyle practices.