Lots of good advice here, thanks, we're getting organic veggies every week from quecomescuandocomes, jantango's recommendation I believe. Lots of green stuff, my girlfriend's face goes green too when the bags arrive. Basically the idea is no sugar, minimal fruit (and occasional orange juice), as few carbs as possible, no bread, no pasta, almost no rice or potatoes, lots of protein and fibre, and some fats (olive oil, avocados).
And yes, it's not just diet, but exercise as well, we used to walk a lot, one hour per day easily all around Recoleta and Palermo, so we're starting to do that as well, and adding daily workouts as well. The lack of activity in the earlier parts of quarantine here took their toll. We're not going to be going to the gym anytime soon though, even if they open, the gyms here are generally utterly unhygienic, none we've seen have paper towels and disinfectant spray for the machines after use, and the shower / toilet facilities are generally unspeakable. I really can't see the gym opening going well.