What is more effective?

Long term or short term? If you think very short term, then starving yourself, however if you do this it is extremely unhealthy and it starts to eat away at your muscles not your fat, so you are mainly losing muscle (not the kind of weight you want to get rid of). Also once you start to eat again, your body will store all the food you consume into fat. This happened to me, I didn't starve myself on purpose but I had my appendix out and didn't eat anything for like 10 days and lost 10lbs, then once I started to eat again (even though I was eating healthier than before), I put on 20lbs really quickly! I weighed even more than before the surgery. This is the reason you are not losing any weight, because you are starving yourself some days, and eating others, your body is putting all that food into fat. So to get back on track and start losing weight, I would reccomend increasing the amount of food you normally eat when starving yourself over a period of 3 days, and eat healthy, regular amounts (eat your BMR), and you will start to see results after a few weeks. Don't expect to lose weight really quickly. Also, don't hate yourself for having a treat, they help keep you on track and stop you from ending up binging.