Coffee anyone?

Why is this important?

Another interesting study that looked at glucose control in relation to sleep quality and coffee consumption. The role of caffeine and its role in improving exercise capacity is well established yet the role of caffeine on fat burning and glucose control is a little less clear.

Conventional Wisdom

There is a fair bit of media coverage at the moment relating to sleep and its effect on glucose control and insulin sensitivity. It has been proposed that one night of bad sleep can negatively impact the following days control from a physiological standpoint - poor glucose control and reduced insulin sensitivity. Further to this, a bad night's sleep can impact your decision making by influencing areas of the brain that like reward and push you towards sweet and fatty foods. Pretty incredible. Couple this with prior research highlighting differing responses to coffee in the morning, the study sought to answer a few questions relating to the impact of sleep quality, black coffee and a high carbohydrate drink on glucose control.

Tinlane Perspective

The issue I have with this study is that who the hell drinks a sugar containing beverage for breakfast? If you are doing that, you have bigger concerns than your morning black coffee. It would have been great to compare the sugar drink with a high protein food choice and reveal the blood glucose response. This would have been minimal despite the coffee and perhaps led to some further insight into the choice of food for breakfast can significantly impact your blood glucose levels. The other interesting aspect about this study is that research completed in 1967 reported a similar effect on glucose levels after black coffee consumption. 

Key Takeaways

I will keep it succinct, 

• Effectively one night of bad sleep does not affect your glucose metabolism, so you can hold despair and not worry about your newly implanted continuous glucose monitor attached to your left tricep (this is extremely trendy right now if you did not know). 
  
• If you have a coffee before a high glucose containing beverage then you will see a significant spike in blood glucose levels and subsequent insulin response. 
  
• Other research investigating short time frames (e.g. 1-3hrs post consumption of coffee) have found black coffee consumption to increase the area under the blood glucose curve (spikes blood sugar),
  
• Long term studies have found it actually improves blood glucose control.
  
• Regardless of the short term or long terms studies on black coffee consumption - DO NOT DRINK A SUGAR DRINK FOR YOUR STANDARD BREAKFAST.  Problem solved.
  

1. Harry A. Smith, Aaron Hengist, Joel Thomas, Jean-Philippe Walhin, Philippa Heath, Oliver Perkin, Yung-Chih Chen, Javier T. Gonzalez, James A. Betts. Glucose control upon waking is unaffected by hourly sleep fragmentation during the night, but is impaired by morning caffeinated coffee. British Journal of Nutrition, 2020; 1 DOI: 10.1017/S0007114520001865