HELPPP!!

your body maybe going into starvation mode everything you eat your body will hold onto since it doesnt know when there will be more food...thats 1 thing that might be happening or you just arent working out enough or drinking more water. idk what are you doing for workouts,eating,drinking etc..??

This is a great article that could help you.

http://www.webmd.com/fitness-exercise/guide/make-most-your-metabolism

reallly pay attention to the section heading "revving your engine" and "Eat more, burn better"

What I've noticed is that people are posting enormous calorie burns for moderate exercise. I suspect most of them are over-estimating their exercise calories and that is wiping out a lot, sometimes all, of deficit that MFP sets for them.

In the OP's case, it's impossible to know what's going on because not enough information is provided. Things to look at are:

(1) Is the BMR that MFP is calculating for you accurate? Many morbidly obese people have yo-yo dieted for a large part of their lives and their metabolism is slower than average. As a result, the amount of calories MFP and other online apps predicts they need for maintenance is way too high. I remember when I first started, the online calculators said I should be losing 2 lb. a week but I was only losing 1. They also said I needed 2600 calories a day to maintain my weight. But I was only 223 and not exercising. I was eating around 2200 a day and my weight was stable. So the online calculators were giving me 400 calories a day too much -- with a 500 calorie a day deficit, I would only have to be off by 100 calories to erase my deficit.

(2) What did you pick for your activity level? If you are inputing your exercise calories, then you shouldn't include your exercise as part of your activity level because then you are counting it twice. (The directions aren't clear about this IMO.) If you have an office job, your activity level is probably sedentary.

(3) How are you calculating your exercise calories? The online databases tend to over-estimate for some exercises and under-estimate for others. The machines at the gym have the same issues. The most accurate estimate is to wear a heart rate monitor and then round down what tells you (even the most accurate can be off by 10% and they work better with cardio than with strength training)

(4) What kind of deficit did you ask for? If you only have 25 lb. or less to lose, then 2 lb. a week is probably too much. On a related note, when you say you are under your calories most days, are you talking about being under by 50 calories or 500? 50 is noise. If you are regularly under by a large amount every day and you aren't morbidly obese, you will slow your metabolism.

However, "starvation mode" as it's expressed by many on this web site is largely a myth. No one leaves a concentration camp morbidly obese. If you eat less than you burn, you lose weight. In studies where people ate 50% of their calorie needs, their metabolism did slow down but it took months to get down by 40% and they still continued to lose weight (they were still eating 10% less than they were burning). You definitely aren't going into "starvation mode" if you are under by 50 calories a day, either, even if you do that for days at a time.

(5) Are you measuring your food or eyeballing it? Studies show that people routinely under-estimate their portion sizes if they eyeball.

(6) Are you doing a lot of strength training or recently upped your exercise? Muscle repair requires water storage and so for the first week or so, you might not see a loss on the scale. But, if you go a month with no loss, then I'd start looking at your numbers and seeing if you have inaccuracies anywhere.