i went on a 1000 calorie a day diet, which i found hard to live on for more than a few weeks but i lost 3 stone in 6 1/2 weeks!, and i didnt eat anything that i couldnt work out the calories of, weighd everything, even cerial, and i kept a diet diary which i found the most usefull as i could tally everything up throughout the day, and it helped mentally x