The sugar diaries (1): Experiments with my pancreas

This is the story of the continuous glucose monitoring device that I had for 10 days, allowing me to do "experiments" with my own pancreas. 

The sensor sits just under the skin, checking the sugar level in my interstitial fluid every 3 minutes and sends it via Bluetooth to my phone. So neat!

Here's what the app looks like, you can see the rises and falls in real time and the trends over the course of the day. 

The Objectives:

I wanted to know:

A. Do I have diabetes or diabetic tendencies? 

B. How does my body respond to different carbohydrates?

C. How do the "healthy" foods stack up with the "unhealthy foods"?

Part A. Do I have diabetes?

Viva my pancreas! I am generally a healthy person and I eat a good variety of foods, but I don't exercise much. Like many people, I carry a bit of extra weight around the middle. My GP said last year that I was 2cm away from being overweight by waist circumference criteria, though my BMI is a normal 23.  

Throughout the 10 days, I was consistently gobsmacked by my pancreas. Thanks to my wonderful pancreas, I release insulin steadily in response to food and most foods make me sit in a relatively "normal" range. For reference, target healthy levels are 4 - 7mmol/L fasting (mine averaged 5.0 to 5.5) and 7 - 10mmol/L after meals (mine was usually between 7 and 9). 

The app also calculated my overall average glucose to be 5.6mmol/L with a standard deviation of 1.0mmol/L - pretty amazing statistic!  

Exercise predictably dropped the blood sugar by 0.5 - 1.0mmol/L  depending on how much I exercised. I even had a few hypos which the app defined as less than 4.0. The lowest I got was 3.4 after gardening. Interestingly my blood sugar level did not seem to correlate with any feeling of hunger. 

Part B. How does my body respond to different carbohydrates?

I expected different sources of carbohydrates to have different impacts on blood sugar level, since this is the whole premise of the glycaemic index. What I didn't know was that the shape of the curve would be different - some carbs made my blood sugar rise slowly with a gentler peak, others caused it to surge straight up.

Clockwise from top left: (1) Fettucine with ragu sauce; (2) Veggie pasta sauce, 1x sourdough with blue cheese; (3) Kara-age chicken bowl on brown rice; (4) Wonton noodle soup 

There were plenty of surprises! Pasta was nowhere near as bad as I thought it would be, giving me tiny peaks even though I ate hefty servings. I tried pasta quite a few times too, I love pasta and obviously, pasta loves me!

Clockwise from top left: (1) Cauliflower potato hotpot; (2) Mashed potato (with cream); (3) Instant noodles; (4) Chinese lunch of red braised pork, eggplant green beans, choko salad and rice

The "ordinary Chinese lunch" that I have with family came in surprisingly well though I ate a whole bowl of rice. However, the dinner I had at a dumpling restaurant was surprisingly high. The cauliflower potato hotpot sent me to such heights, perhaps because they put a lot of sugar in the sauce? 

There was definitely a clear effect between highly refined vs. harder to break down carbohydrates. My own sourdough consistently brought me to the 6 - 7 range, which made me very happy!

And... who would have known that breakfast would turn out to be the most controversial meal?

Clockwise from top left: (1) Weetbix granola fruit yoghurt; (2) Oatmeal; (3) Sourdough pancakes with yoghurt and maple syrup; (4) 2x weetbix, an egg, a tomato and a glass of milk

From these photos, is it surprising that 2 weetbix was the lowest? Probably not. Oats with no honey added still got to a decent 8. But the biggest surprise was that the breakfast that sent me close to 9 for the first time was one plain weetbix, a handful of muesli (to "break up" the taste of weetbix), fresh fruit and yoghurt. 

Everyone I asked said this looked like an amazing healthy breakfast. 

Who would have guessed that the reading after 3 decent sized pancakes with a generous splodge of maple syrup would be identical to the Weetbix with fruit and muesli??

That's all for now. Next time, I'll focus on the snacks, the "winners" - the foods that sent me through the roof, and my attempts to get my own BSL to 10!