For example, I've heard that some people have spikes after eating bananas, but other people do not. Also, rice can be very bad for some people (and different kinds of rice have different effects). I'd be curious to wear one for a month or so just to see how my body reacts to various foods and combinations of foods. I think it's possible to rent devices that do this, but it's hundreds of dollars for not that long of a trial. If I could spend $400, gather data for a month, and then sell the device in like-new condition for $250, that'd be a win in my book.
For example, if I could make my liver 20% healthier by eating more moderate portions of bread in a meal where I plan to eat dessert, it would be useful to know that.
On the other hand, I don't think I have to wear the device forever to gain this information. I could learn about what makes my blood glucose spike after a month or two, and then just carry that knowledge with me going forward.
I mean, the potential health benefits in terms of preventive care seem to be incredibly large to me.
It made some sense to me, but ultimately considered it would work out for the greater good.
So I feel like your doctors maybe don't understand or appreciate technology.