It is NEVER a good idea to lose weight too fast, you have way more chance of putting it back on really quickly! Deprivation never worked for anyone, apart from those anorexic girls/guys you might see. My sister has been addicted to laxatives, and is now the size of a stick. She is in treatment for bulimia, and her guts are soooo messed up it isn't funny. Firstly, tell Grandma that commenting on your weight is only going to hurt your feelings, and while its nice she's worried about you, this is something that is yours to do and not hers to comment on. Then up your water intake. It will flush your system and help things flow. 2 litres per day (hard to do at first, put some lemons in and drink it ice cold). I bought a tupperware style jug that has a good sealing lid on it, and am amazed at how easy it is to drink the 2 litres now. Eat a good breakfast, include some proteins if you can stomach them first thing, like an egg on toast. Try organic breads if you can find them/afford them. Try eating a substantial lunch (including vegetables and protein), allow yourself to be satisfied. A smallish snack as late as possible, can be carbohydrate, but nothing too sugary otherwise cravings will kick in. Things like rice wafers are good with tahini/small amount of peanut butter. Cut down fruits (quite sugary) but don't forget a piece or two per day for vitamin intake. And vegetables are your friends! Cut down carbs like bread (I don't advocate cutting them completely!), cut down fats but not to a ridiculous level. Olive oil is great, and if need to add in some omega 3 supplements. If you want to follow a good diet, try the blood type diet book (not a starvation diet, but a change in eating habits). Its designed to work with your body's needs, and there is no deprivation or counting calories. Or a liver cleansing diet, but definitely not one that advocates eating pitiful amounts of food. I have an eating disorder, and am constantly amazed at how little food some of these "diets" expect you to eat and cope with. I always, always end up worse than when I started. The only books that have never caused a problem are the ones I mentioned. They allow you to EAT, and not feel deprived. I attended an eating disorders group, and was convinced that they were right by the end of it - starving causes eating disorders! Good luck - I hope you can manage what I never could - pride in yourself for being who you are, regardless of your size. Its hard not to obsess about the weight loss, I know. Eat good foods that are good for your body.