FWIW I managed to lose around 8-9kg / 10% of my body mass at a rate of about 0.5kg/wk on low carb / keto; along with a further, similar amount through extended water-fasting over a much shorter timescale (which Keto opens the door to as it kills the carb craving and makes it so much easier).
It definitely works for weight loss and while the diet can be pretty difficult to accomodate (everything has carbs in!) it's nice to be able to eat stuff you'd otherwise avoid on a traditional diet (I was eating fried eggs and halloumi for breakfast and the weight was still falling off). Once you've sacked off the carbs suffiicently the cravings subside and you generally find yourself eating a lot less; avoiding the while carb-fuelled blood sugar spikes and deficits that underpin the insatiable urge to eat more.
In the long term though it can be hard to stick to, and I find that I have an "all or nothing" attitude to carbs; I'm OK when off them pretty much completely, but trying to reintroduce them opens the door to the cravings again and soon I'm wanting all the crisps and chocolate. It also helps to be happy and otherwise have a stable, low-stress life (yeah, right!) as eating tends to be an emotional crutch for many (myself included).
Ultimately I think Keto's great for targeting weight loss but I'm less convinced as a long-term strategy due to the practical aspects of such a restrictive diet and lack of long-term data. Once at a decent weight I think a more sensible approach (assuming you can tread that tightrope) is low-carb; sticking only to low-GI foods and avoiding all the nasty high-GI, sugar-laden processed crap.
I'll just leave this here, Dr David Unwin a well respected , experienced GP passing a wonderful message.
https://mol.im/a/8084971
While I'm dubious of anything presented as fact by the Daily Fail, I do know at least two folks personally who've come off diabetes medication after following a low carb / low GI / Mediterranean diet to control their blood sugar fluctuations
