why is this happening to me?!

need more info

Perhaps you are gaining muscle from your consistently rigorous exercise?
It could also be water retention from high sodium intake.
And it could be underestimating your food intake.

Eating under your calorie goal might be putting your body into starvation mode. And you need to eat back some if not all your earned exercise calories!

maybe meet your calorie goal or increase your calorie goal.

Your body needs 1200 calories to maintain all it's functions on a daily basis -- for your heart to beat, for you to breath, for your brain to work. If you were to sit still for 24 hours, your body would STILL burn 1200 calories.

Because of this, you need to make sure you always eat at LEAST 1200 calories -- so you can support these daily functions. But as humans don't just sit still all day long, your body is most likely burning a lot more than 1200 calories, depending on your activity level -- which is why many people on this website stick to the 1400-1600 range, to make sure that they're always above that 1200 mark.

So the next question is, what happens if you dip below that mark. If you do it once, not a big deal. However, when you're consistently under 1200 calories, your body goes into what's called "Starvation Mode". The scientific reason is that the human body is ridiculously adaptable and well equipped to survive.

So, when you're eating less than 1200 calories, your brain assumes that the reason you are not being adequately fed is because you are in the middle of a famine -- as a response, the brain starts to slow down as many "side" functions as it can, in order to save energy and fat stores -- to survive this "famine". The main "side" function -- your metabolism -- It slows WAAAAYYY down.

So by not eating 1200 calories, you're forcing your body into starvation, and actually hindering your weight loss.

Will you lose weight? Yes, over time you will -- but your body will burn through it's own muscle until you become a skeleton. (I suggest you google anorexics)

WIll the weight that you lose stay off? No. The INSTANT you start eating again, your body will actually STORE extra fat from the food you've eaten -- in this meal is the only one you'll be getting for awhile (Starvation response). Your metabolism will STILL remain very slow, and you will gain weight back.

You've got to think of your body as a machine. In order to lose weight, you need to allow your body to streamline itself -- to do this, it needs to run in peak condition so it can shed the excess fat it has. Feed it.

Don't Believe me? Google it. Search this site's forums. I dealt with an eating disorder for a very long time, eventually went to a nutritionist to help me understand the above concept. Because of my past with dealing with this, I am very sensitive to those who I believe abuse this website -- either by deliberately not feeding themselves or by congratulating others who are WAY under calorie.

eating 500 calories between breakfast and lunch, is not acceptable

thats what someone told me what i was doing but i cant eat 1200 cali

Perhaps you are gaining muscle from your consistently rigorous exercise?
It could also be water retention from high sodium intake.
And it could be underestimating your food intake.

No, will not be muscle gain with a large caloric deficit.

i am in the same boat as you, i am gaining a little weight as well. However you say you are working our vigorously, so your body is gaining muscle. muscle weighs more than fat, so maybe next week take your measurements and see if you have lost anything their. also make sure you are eating enough because if not then your body is gonna store everything you eat and not burn it off, hence starvation mode. but dont give up, keep going and all your hard work will pay off in no time.

Need more food and more water!!! Your body is probably reatining water due to the increased physical exertion which is why it seems like you're gaining weight. Your muscles will retain water after you exercise to repair the damage that was done by the workout. It sounds counter-productive, but drink more water. This will trigger your body to excrete more water due to the influx of water and will help flush your system of the bad stuff that your body puts out when you exercise as well. If your net calories are under about 1200, then you're probably not eating enough which will also trigger your body to conserve and will cause you to put on weight. This will usually only occur after an extended amout of time, though. Depending on how long you have been working out and dieting, the culprit in this case is probably water gain.

Another thing that will cause you to retain water is sodium. Track your sodium and see what your intake is. You will probably be surprised at how much sodium you take in on a daily basis without even trying.

Hope this helps and good luck!!

If you make your food log visable we will be more likely to help you.

Most of us, myself included, are quite poor at estimating food portions. Are you measuring and weighing your food?

How far under your daily calorie goal are you? If you set up MFP right to start with then the daily calorie goal that MFP gives you already has a calorie deficit built in to lose weight. That said, you should eat close to the calorie goal MFP gives you each day including eating back most of your exercise calories. Depending on how far under the daily calorie goal you are, you are very likely to cause your body to hang onto the fat it has by either slowing down or even stopping fat loss. It may not happen right away but eventually you will most likely plateau. If you have a lot of weight to lose you can probably get away with it longer but as you have less to lose your body will plateau easier. May sound counter-intuitive but that's just the way it is.