I definitely agree with you that the absolute, unwavering adherence to an eating window isn’t sustainable long term, but what you’re describing just blatantly is not intermittent fasting. You just are dieting by not eating as much. Your weight is dropping because, by virtue of only eating during a 4 hour window, you are naturally eating less calories (most likely by snacking less) throughout the day than you otherwise would.
The sugar in your wine is completely irrelevant to the fast. The calories in the wine are kicking you out of your fasting window. If your 20:4 hours are 2:30–6:30 and you’re drinking wine prior to 10:30, that’s totally fine, but you aren’t doing 20:4, you’re doing 16:8. Any calories (this is where the ’50 calories is fine!’ idea comes from) outside of your eating window resets your fast. A glass of wine, regardless of the sugar content, is going to have at least 100 calories in it. As soon as you drink that glass of wine, your fasting period is reset.
You’ve spent this entire article talking about how deprivation doesn’t work for you, but your diet actually is deprivation. That’s why you still get hungry / peckish outside of your window. If you had strictly adhered to it, you wouldn’t feel hungry outside of the window after doing this for so long.
For me, I do 20:4 M-F with my window being 6:30–10:30 PM and on weekends I do 16:8 with a 2–10 PM window. So I know what you mean by saying you can’t strictly adhere / it’s more trouble than it’s worth, but don’t call an apple an orange.
