Hi Bakeja
Last year I lost 5 Stone and have kept the weight off. I only adjusted me diet slightly. Eat less fat, but did not cut it out completely, in fact did not cut anything out at all. I still drank 2-3 times a week, had the odd kebab/ meal out etc.
For me the key was exercise, not diet. Thin people eat all sorts of junk. I think it all comes dowm to metabilism. If you dont exercise you metabilism becomes slow. You do not need to do alot to start losing the weight. I would walk briskly for about 4 miles (takes about an hour) most days.
If you're like me, I never exersised, so starting was a real drag, but after about 2 weeks I actually enjoyed it. I also found out that if you do strenuous exercise ie running, you run the risk of increasing your weight as you will build musle, which is heavier than fat.
This worked for me. I'm 52 - it took about 10 months to lose the weight
O and drink lots of water - 5 pints a day if possible
Phil