Yes, I am on Warfarin 5mg a day, and started the 5.2 on 1st June, and have lost approximately 2 stones…I Fast Monday and Thursday and visit the nurse for INR test every week with INR between 1.9 and 2.7…have the diet more in control now and the nurses and the Dr’s are very happy with my weight loss…I will stay with this programme because it works. and I eat a lot healthier..tried other diets and could not stick with them…hope that helps…just discuss it with your surgery..and do it…but check INR weekly.