Diet and exercise together would allow you to meet that goal, but make sure that you take some vitamins and if possible check in with your doctor, just in case you have a condition that might be best to monitor.
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It is NEVER a good idea to go below 1200 calories for anyone. In your case, I'm assuming your a growing teenager who, as a bare minimum, needs at least 1500 calories to function properly, and that's not even including the energy you need to have for normal things such as walking or even typing on the keyboard. If you go below 1200 cals your body will go into something called starvation mode, in which your body stops using energy for the less important things such as your hormonal system, which will result in you losing your period and most likely the chance of you ever being able to conceive permanently because of the massive stress your body is under. You also have the risk of developping full-blown anorexia, which in most cases with lead to death. Anorexia is a TERRIBLE disease, believe me, I've had it before, and I'm in recovery now. No matter how much you want to be thinner, its not worth it. Have anorexia - for me - was absolute Hell. Anyway when I had it, I got down to the lowest weight possible which for me was 88 pounds, which might to someone with anorexia is the best thing possible, but I looked horrible, my ribs protruded, my eyes looked sunken in, my arms were, literally, stick-like, and to top it off, my lack of food made me irratatted constantly and I often fainted and woke up hours later with no idea what had happened. To cut a long story short, I spent 3 months in a hospital recovering, just to be able to go home, where I couldn't even walk around, and am now still recovering. In the beginning before the whole eating disorder thing, I had been at healthy weight of 110 pounds at 5"2. Yes, the exact same as you, and I too thought I had to lose weight, but now looking at myself now compared to before, I honestly looked better at the normal healthy weight of 110 pounds, then now at 94. My skin was creamy, when now its a dull grey color and dry, my eyes shone and now their sunken in, and my hair, once a thick shining golden blond, now looks like a floor mop, thinning and dull. Losing weight is never the answer, unless your very obese, and your health is in danger. In your case, by losing the weight you'll put your health in danger, when in reality your at the ideal weight for your height.
It is pysically impossible to lose 7 pounds in a week.
since 3,500 calories = 1 pound, you need to lose 7,700 calories per week to lose 2.2 pounds per week.
1200 Calories
you will lose about 5 pounds. Because for every 3400 calories you burn it is a pound, so take 17500 and divide it by 3400
you have to lose calories you do that by excising and lose 500 calories each say for one week no junk food you will lose 1 pound in a week if you only lose 500 calories each or 1000 each day you will lose 2 pounds
depending on how active you are and how much you want to lose a week would help. there are 3600 calories in a pound so if you cut out a 1000 calories a day you will lose about 2 pounds a week without exercising. So if you eat about 1200 calories a day and work out to burn about 300 calories a day you will lose 2-3lbs a week.
2 pounds if you do not increase your activity level. For every 3500 calories you will lose one pound.
In order to lose one pound, you need to burn 3500 more calories than you take in. If you want to lost 2 pounds in a week, you need to burn 7000 calories more than you take in.
6500
500 to 1000
350000 a week
If you are a 16 year old female who weighs 257 pounds and is 5'5" tall, consuming 1,200 calories a day would help you to lose 3-3.5 pounds per week.