I lost my excess weight (about a stone) over 4 months, by lowering carbs. I did it gradually, swapping refined sugar products out (cakes, biscuits, sweets & sugary syrups, jams etc), then white goods (white pasta, white rice, potatoes, white bread). Then I cut brown carbs (whole grains) that I had substituted in down to smaller portions. I don’t go by the lowest level to actively remain in Ketosis, but bought a testing kit after a while and noticed I was often in ketosis on the relatively small amount I do ingest each day. That includes a small bowl of muesli with s little fruit and yogurt at breakfast. And I’ve gradually worked out that I can eat a little bit of dark chocolate and the odd sugar-free biscuit. I use a little xylitol to sweeten anything where I’d miss a sweet taste. But as you’ll hear a lot here, everyone is different! This is just what has worked for me. It hasn’t quite been a year yet so I’ve yet to learn if there’s been a further drop in my HBa1c but it had dropped by 1 marker last time. Just 1 more, I think, and I will be considered non-prediabetic. Good luck!