Quantifying Blood Glucose Impact of Low-Carb Foods & Ingredients

I’m getting back into self-experimentation after being distracted for a while from starting a new job.

This will be my research log for studies I’m doing on blood glucose impact of low-carb foods & ingredients. I post incremental updates at www.quantifieddiabetes.com and will collate/organize them here for people who want to follow along.

Completed Studies:

  • Effect of Low-carb Ingredients & Macronutrients
    • Report
    • Ingredients: glucose, corn starch, whey protein, olive oil, oat fiber, resistant wheat starch, inulin, allulose, erythritol
    • Summary of Conclusions:
      • The main macronutrients, carbohydrates, protein, and fat have the expected impact.
      • Insoluble or “indigestible” fiber had a wide range of impact, from near zero to 76% of glucose for resistant wheat starch.
      • My two preferred non-nutritive sweeteners, allulose and erythritol had negligible impact.
  • Meal replacement & Butter
    • Report
    • Foods: Ketochow, butter
    • Summary of Conclusions:
      • Ketochow had the expected impact based on its nutrition label.
      • Butter significantly slowed the rise in blood glucose, independent of amount used.
  • MSG
    • Report
    • Foods: Ketochow, butter, MSG
    • Summary of Conclusions:
      • 10g of MSG causes a large increase in blood glucose when eaten with Ketochow
      • This effect only occurs with meals & without insulin. When I take MSG alone, or add insulin to cover the meal, I see no effect.
      • This is really strange, but I’ve repeated the experiment and gotten near identical results.
        Low-Carb Tortillas
    • Report
    • Foods: 6 different low-carb tortillas
    • Summary of Conclusions:
      • Tortillas using oat-fiber or cellulose fiber have ~50% the blood glucose impact of those using resistant wheat starch.
  • Low-Carb Cereal
    • Report
    • Foods: 7 different low-carb cereals
    • Summary of Conclusions:
      • Impact by weight: nut & seed granola << milk protein & sweetener << Catalina Crunch
      • Impact by volume: nut & seed granola ~ milk protein & sweetener << Catalina Crunch
  • Low-Carb Ice Cream
    • Report
    • Foods: 6 different low-carb ice creams
    • Summary of Conclusions:
      • All ice-creams held up to their claims and had relatively low and similar BG impact.
      • Keto brand ice cream was ~25% higher than the next worst, but there’s no clear indication why based on ingredients (the problem with nutrition lables not specifying quantities…)
  • Low-Carb Bread
    • Report
    • Foods: 14 different low-carb breads from 4 categories
    • Summary of Conclusions:
      • Huge variation in taste, texture, and BG impact, even within categories.
      • Lowest BG impact: UnBun UnBread
      • Best combination of taste & BG impact: Carb0naut White & Kiss My Keto Golden Wheat
      • BG impact is not easy to predict from the primary ingredients or nutrition label due to not knowing the ingredient ratios. Breads with actual flour can have the same impact as ones with indigestible fibers and two breads with the same total and/or net carb count can have wildly different impact.
      • Large range of impact from resistant starches, suggesting some are more/less digestible than others. If I can find sources, I’d like to test different starches directly to figure this out.
  • Low-Carb Chocolate
    • Report
    • Foods: 13 different low-carb chocolates from 4 categories
    • Summary of Conclusions:
      • Lowest BG impact: Lily’s Almond Dark & The Good Chocolate Signature Dark
        • ~65% of the impact of 100% cocoa bars
      • Best combination of taste & impact: Taza Wicked Dark & Trendz Bar
      • Chocolate with added fiber shows much higher blood glucose impact
        • There’s a significant variation between brands
        • This could be due to different fiber type or quantity
      • Watch out for the ChocZero chocolate, which gave ~2x the BG impact of the next highest chocolate.


  • Does anyone have any suggestions for other foods, ingredients, supplements or interventions for me to try?
  • I’m also always looking for collaborators for future experiments. If you’re interested in collaborating on scientifically rigorous self-experiments with foods, nootropics, sleep aids, or anything else, let me know.

This is a super interesting result. It seems like something others could try. I haven’t done blood glucose testing since a few weeks experiments with the Freestyle Libre, but I found it pretty easy to get the measurements and I’m intrigued. Will look into it!

Yeah. Fat slowing down absorption of carbs is pretty well established, but I was surprised at how little it took to saturate the effect. 1 tablespoon was enough to do it.

Yes it’s the independence of amount that was really surprising to me.

i did a small data analysis and have found that even having dinner before 17:30 makes my postprandial glucose (CGM) elevated (in a healthy range) until 22:00. Maybe you will be interested to look. It seems not only matters what you eat but also when you eat.