Two weeks ago I wrote about the next phase of Project Food as Fuel. I have been wearing a continuous glucose monitor (CGM) for fourteen days, and I’d like to share some observations so far.

• More data is better - Obviously continuous monitoring is clearly better than capturing one data point every day. My eyes have been opened to the real trends occurring in my body on a daily basis.
• Accuracy matters but relative accuracy matters more - In general, the readings from the CGM are lower than actual blood readings by 5-20 points. Even though the CGM data are not as accurate, the trending is still valuable. A lower reading compared with another lower reading still matters.
• The meals I used to eat–YIKES - I admit I have had some meals in the last two weeks that are not approved for Project Food as Fuel. I was curious about what effect these specific meals have on me. Of course, carb-laden meals spike glucose (no surprise), but what did surprise me is how long my blood sugar remained high. One day I had a croissant breakfast sandwich and a donut (shame, shame!). At about 7AM my blood glucose started to rise and it peaked just over 200 mg/dL about four hours later. For reference, normal blood glucose levels for non-diabetics should be less than 140 mg/dL two hours after eating. My blood glucose did not get below 140 mg/dL until over six hours later! Needless to say, I fasted the rest of the day to recover from this terrible onslaught. I have several more examples that illustrate the same pattern, but I shall spare you the gory details and spare myself the shame.
• Proof of the Dawn Phenomenon - One of my frustrations has been checking fasting blood glucose first thing in the morning and getting high readings (130 mg/dL or higher). Logically, this makes no sense. If I haven’t had any food since dinner twelve hours ago, and all I’ve been doing is relaxing and sleeping, why is my blood sugar so high?? The Dawn Phenomenon occurs in about half of people with diabetes. It is marked by an increase in blood glucose during the night and peaking about 1-2 hours after waking up. The underlying mechanism is not fully understood, but it is related to insulin resistance or a lack of insulin. The consistent trend I have seen is blood glucose is lowest around midnight to 1 AM, then it slowly rises throughout the night and peaks shortly after I wake up. There are some strategies to mitigate this phenomenon. 

Eat dinner earlier in the evening and avoid late-night snacks. 

Make dinner the meal with the least amount of carbs. 

Have some sort of light activity after dinner. 

Make breakfast as low carb as possible. 

Last night I did not eat dinner. What I noticed is that the Dawn Phenomenon still exists, but it took longer to get there. My blood glucose did not start rising until about 5 AM.

• Exercise causes blood sugar to go down - I knew this, but it’s nice to see the trend in the data. In fact, doing some sort of exercise after a meal, could be as simple as a walk or a bike ride, helped keep blood glucose from spiking.
• The keto diet is working for me - When I behave and stick to Project Food as Fuel, my blood sugar stays within normal targets (70 mg/dL - 140 mg/dL). I have more energy and focus, and I just generally feel better. By the way, all this is happening without any medication.

What’s next? Each sensor only lasts 14 days, so today I will ditch the current sensor and attach a new one. Other than a trip to Vegas, I have been home these two weeks. In the next two weeks I have back-to-back trips to California. I look forward to more insights with life on the road.