This is the type of thing that the linked studies refute - there are either too many external variables to control, or our bodies glucose response is far more complex than we currently understand. Or both - both of the above seem possibly true at the same time.

Either way, if something as simple as eating a few bites of bacon before you eat your toast can change your glucose response, manually logging your meals for Zoe isn’t gonna provide enough data for any reliable extrapolations.

> And they can extrapolate to other foods that you didn't eat during the testing period.

I would need to see an independent researcher confirm they can do this. As of now, I don't believe they can, and I'm not even sure the theory is reasonable.

A CGM is not easy to use reproducibly. The quality control of the manufacturers is not that good, the placement of the sensor (particularly if it is near a place where insulin injections have caused lumps under the skin, or if it is on the back of the arm, where there may not be a lot of flesh) may cause some troubles, the calibration process is dubious, since CGM readings lag blood glucose by around half an hour, rapidly changing blood sugar levels seem to confuse the monitors, and very high or very low blood sugars seem to cause the accuracy of the sensors to deteriorate noticeably a few days prior to their respective expiration dates.

And how do you know that the logs are accurate? The best subjects are incarcerated subjects.

All that said, it's a long row to hoe, and the monitors are definitely worth all the annoyances; they are way better than peeing on a strip of testape like we did back in the old two-holer. But science is very hard.