AM I eating too little?

Your diary is private but are you:

A) hitting your calorie goal every day?
weighing and measuring your food?
C) eating back your exercise calories?

If yes to all the above try calculating you BMR and aiming to NET at least that every day.

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This information would be helpful.

My experience has shown me that basing your diet on a 2000 calorie generality is one of the biggest mistakes we continue to make, the FDA standard was developed back when Food labels were first being added to foods, the government needed a baseline and dismissed the 2,350 calorie average it had determined because it thought it was too high. Additionally, the range of caloric sustainment in their test samples ranged from 1800 to as much as 3000. The point here is that body composition, activity level, metabolism, age, and sex play a huge part in the total numbers of calories our bodies require us to consume a day...this is why some people can eat like a horse and stay thin and some of us get hevy just looking at food. There is truly no way to determine your caloric need (besides the point that it can change from year to year) without proper metabolic testing....But all is not lost and it can be summed up this easily...if you are gaining weight you are eating too many calories, if you are losing weight you are eating under your daily needs, and if you are not gaining or losing anything then you are eating exactly what you need to maintain. The 2000 calorie diet is used in MFP and then depending on how many pounds you want to lose it adjusts that number down, but like I said...this is no golden number is going to ultimately depend on you...which is why you can customize this for lower than normal. I am a large 6' male and if i were to eat 2,500 calories a day...heck even 2,000 calories a day I would gain weight. My body just uses calories more efficiently which means I need less...sucks for someone who loves food and variety but it is a fact...if I want to splurge I must equal my calorie increase with exercise. When I want to lose weight I have to reduce my calorie intake to no more than 1,000 to 1,200 calories and that is with exercise. So to sum it up, your body is different than any body else out there, and while many may say that "don't go any lower than that" or "you should be eating more" you must remember that your body is your body and their evaluations are generally based on the political figure point of 2,000 calories or their own experiences. If you are not losing weight you can continue to reduce your calorie intake until you do find yourself losing weight...remember approximately 3,000 calories is a pound. So, if you are maintaining right now then either increasing exercise or cutting out something else will eventually lead to weight loss.

Yes, Yes and Yes! I have tried calculating my BMR and each site gives me a different answer. I am 5'3" 167 lbs female, 21 years old

Well,

Based on the information provided and using MFP BMR calculator it says your Calorie intake should be about 1400 a day to maintain...I believe you said you are consuming 1350 a day. I would definately say that when we add our cals in it is plus or minus at least 50 calories...possibly more depending on the methods you use to determine your calories. If that is the case then you are eating basically what you need to maintain your current weight. If you are in fact only eating 1350 a day then it would take you two months at your current deficit to see any weight loss. I believe weight loss can be a little more radical than most...but to stay within what most folks on MFP deem "healthy" weight loss, you can effectively lose about 2lbs a week and remain in that healthy range of weight loss. If you want to lose 2 lbs a week...based on your BMR....then you would need around a 7000 calorie deficit in that same time period. It sounds like a lot, but dont be freightend by that number...just break it down. 7000 calories comes out to a 1000 calorie deficit a day. Now obviously a 400 calorie diet is not going to net you the nutritional requirements you need and you are not going to stick with it...so you have to supplement that with exercise. If you reduce your diet by 200 calories a day (might not be as hard as you think if I could see your diet) and you include 60 minutes a day of walking you meet the point you will need to be at to lose 2lbs a week.

Do not listen to anyone that says you mustn't eat back your exercise calories. If you are supposed to have a daily calorie goal of about 1300(which already has a built in calorie deficit) and you exercise and burn off 300-400 of those calories you are in fact only netting 900-1000 calories. You need to be netting close to what your goal is. And we need to try to be as consistant with our daily calorie intake as possible. Roller coaster ups and downs don't help.

Based on the information provided and using MFP BMR calculator it says your Calorie intake should be about 1400 a day to maintain...I believe you said you are consuming 1350 a day. I would definately say that when we add our cals in it is plus or minus at least 50 calories...possibly more depending on the methods you use to determine your calories. If that is the case then you are eating basically what you need to maintain your current weight.

I might be wrong, but isn't BMR the ammount of energy you would use if you stayed in bed all day? I think even if you are sedentary and don't exercise at all you times BMR by 1.2, giving 1680 Kcals. If you are moderately active it gives 2170

No, you are right...but the number you multiply by can vary greatly based on an individuals metabolism. I guess 1.2 is a good starting point...but if you multiply it by 1.2 and you are gaining then your body obviously doesnt fall into the "norm"