How to lose weight and keep it off permanently

This is a chart of my weight since the 23rd of August 2012 until around a week ago.  You'll notice 2 sharp drops in my weight, one occurring at the beginning of the chart in August 2012 and another one in June of this year.  I'll talk about the latter one first.

This latter drop in weight occurred in June of this year and was precipitated by moving to another area of the country (in England).  This was very stressful for me and when I worry or am stressed I tend to eat somewhat less than I do normally.  As can be seen I regained the weight after about 3 months or so.  I never tried to keep this weight off, nor did I try to regain my weight. I just ate what I liked during this time period. The fact that it has gone back up to what it was originally, but then stayed there without going further up, suggests to me that I have a natural weight or "default" weight which my body will strive towards. Thus if I lose weight for whatever reason over a few weeks, my body will make me sufficiently hungry so that I eventually regain that weight. But the same might happen if I eat too much over a few weeks. My body will reduce my hunger so that I lose it again.

I further suggest this is why the vast majority of diets fail-- namely because people can only keep up a diet for a few weeks or months since they are constantly having to struggle against their hunger. Once they give up their bodies will make them sufficiently hungry so that they regain all the lost weight. So dieting was a fruitless endeavour because all that happens is that whilst you're on the diet you're hungry for a few weeks or months, you eventually give up, and you just end up putting all the weight back on. So people go through all that suffering (being hungry all the time) for nothing. Moreover, I have heard that constantly dieting, then falling off the wagon, might be deleterious to one's health.

But what about the first drop in weight back in August 2012? Did I move home then too? Was I worried about something? Was I stressed about anything at all?  No, I went on the 5-2 diet i.e a diet where for 2 days in every week I restricted my calorie intake to 600 calories on each of those 2 days. These days were not consecutive. The other 5 days I just ate what I liked. 

So I kept on this 5-2 diet for a few months and lost close to a stone (a stone is 6.5kg or 14 lbs). At that point I wasn't really losing any more so I came off the diet. Why didn't I regain the weight? I'm not sure. One possibility is that the 5-2 diet is more successful than other diets. But I suspect it was because even when I came off my 5-2 diet I still weighed myself every day. On those days where my weight seemed to be a tad high I cut back on my food intake slightly on that day. Those days where my weight was slightly lower I just ate what I liked. At this point I wasn't on a slimming diet, but just frequently checking my weight and reducing my food intake accordingly on occasional days.  I did this for a few months, but I don't do that any longer. I just eat what I like now.  However my "default" weight has changed from what it was prior to August 2012.  It has gone down by almost a stone.

I suggest to lose weight permanently one has to change their "default" or natural weight. The only other alternative to permanently lose weight is to deliberately restrict your calorie intake and fight against your hunger for the rest of your life!  I suspect one can change their default weight by first of all going on a diet (probably the 5-2 diet isn't necessary, but I'm not sure). Then once you're down to a desirable weight to keep checking your weight every day and make slight adjustments as necessary to one's calorie intake. After a few weeks or months then perhaps your body will have adjusted to a new "default" weight and you won't have to do this any more. This seems to have happened to me anyway.