If you reach for the kettle to brew a strong cup of coffee before doing anything else in the morning, you are not alone.
The black drink offers a welcomed kick of caffeine when you don’t feel quite ready to face the day.
However, this popular drink could actually spike your blood sugar levels when enjoyed after waking up, Dr Michael Mosley warned.
High blood sugar can stir up a cascade of health problems, including laying the harmful groundwork for diabetes.
Fortunately, you don’t need to give up the caffeine habit altogether.
Dr Mosley explained that before you wake up, your body releases a “big shot” of the stress hormone cortisol to get you ready for the day.
If you throw coffee into this mix when your cortisol is already high, you will create a recipe for high blood sugar.
What’s worse, the health guru found that even black coffee without milk or sugar has the same effect when monitoring his levels.
Because your blood glucose is already high when you wake up, caffeine can raise your levels even further, but the timing of your first coffee could tackle this.
Therefore, the doctor recommended delaying having your first cup until at least an hour after waking when your cortisol levels start falling.
Dr Mosley penned for MailOnline: “And that trick certainly seems to help control my blood sugar response.
“I also found that a brisk walk soon after eating was a good way to bring my blood sugar levels down — this is because my muscles were using up some of the surplus sugar.”
Keeping your blood sugar levels in check is crucial for a number of reasons as “millions of Brits have abnormally high blood sugar”, the doctor explained.
Worryingly, high blood glucose can deal damage to your arteries and nerves.
Dr Mosley added: “An estimated seven million people in the UK have prediabetes (i.e. raised blood sugar levels that can be a precursor to full-blown type 2 diabetes) — but a good proportion won’t know it, and even if you don’t go on to develop type 2 diabetes, simply having prediabetes increases your risk of premature death by more than 60 percent.”
Fortunately, you can keep an eye on your blood sugar levels by doing a finger prick test that can be bought online.
If the results suggest your glucose is too high, then you should talk to your GP, Dr Mosley advised.