How long does it take to lose 1 stone - which is equal to 14 pounds?

the safest amount to lose in a week is about 1-2 pounds, which, if you lose around 2 pounds a week, can amount to half a stone a month and therefor you could probably lose a whole stone in about 2 months, 3 at the most I would say. You just need to limit your calorie intake to about 1200 and exercise about 3/4 times a week in half hour sessions in things such as cardio work (walking, weight etc) and perhaps funner things like dance :) but tbh ig youre losing more than 3 pounds a week, you should maybe add some calories onto your diet and cut a wee bit of exercise out to balance it out :)