I'm trying to lose some weight at the mo & succeeding by all the looks of it cause any day my trousers are liable to fall down around my ankles without me noticing.
I'm not into tortuous diets & counting every calorie so my doctor advised I eat porridge

(not bl**dy likely)

in the morning or 'museli' cause it fills you up. 'Tropicano' he days is the best juice you can buy though of course water is the best. Plenty of veg & fruit too if you're like me & not a great fan of the first, also chicken, lean meat, fish, skimmed milk, light bread (though I spoil myself a bit with some homemade wholegrain). Careful of those 'Weightwatcher meals' though cause they've a high salt content. Try not to buy too many convenience foods, better cook your own so maybe invest in some low fat cookbooks, Marks & Sparks have a good range of low fat dishes if you must.
Just don't make it unpleasant for yourself otherwise IMHO you'll never keep at it & remember your diet starts in the supermarket. My shopping basket has never looked so healthy in years, if you haven't got cr@p in the house you can't eat it hence less temptation. If anything else the diet I'm on will improve my health goodo.
He also recommend filtering you water, nothing to do with losing weight though but because of the dangerous additives i.e. flouride & chloride that are dumped into them by those well intentioned but misinformed people who manage our water. He's the second extremely knowledgeable person I've heard speak on this issue in a matter of weeks.