Okay to eat below BMR? Losing too fast?

Awesome job with your weight loss!!! If you're losing 1 lb / week, that's spot on and it is definitely not a red flag. In fact, I'd say it's a sign of how committed you are to being healthy.

I am totally curious about this too

Your fine. In order to hit starvation mode you have to take your BMR and divide in half. So if your at 1500 and eat less then 750 calories a day you will hit starvation mode. However, do not eat under 1200 calories because your body will not get the nutrients it needs.

If your BMR is 1500 and you are genuinely sedentary then your TDEE is probably something close to 1800. A reasonable deficit of 25% should have you eating around 1350 a day and you should be losing around 1lb per week on that.

Weight loss will likely be much faster in the early weeks as water weight comes off. Even more if you're heavy in the first place.

Bump. Again. I am confused, please help me out. If my BMR is 1500 ish then what should I be consuming to lose weight without being unhealthy? If MFP is wrong then I want to fix it.

I can't really tell you if the number you're getting is wrong without knowing your stats, height, age, weight, activity level, exercise make-up over a week.

What I can tell you is that generally speaking losing more than 2 lbs a week is not healthy. However for those of us (like me) that started morbidly obese it is very easy to shed significant weight in a short amount of time.

In order for you to lose 1lb of fat, you need to burn up 3500 calories. On a diet, this is usually listed as a 500 calorie a day defecit. Also keep in mind, that if you're big on 'salt' - stop. You will shed alot of weight there. If you're not drinking enough water (want 1-2 clear urinations a day) - drink more water. Additionally, SLEEP. You need a good 7-8 hours of sleep more if possible a night.

It is very easy to rebound on your weight loss if you cut out too much. Look at my profile and look for the post I made on the Topic: "I can't keep motivated" alot of that applies here. If you can't find it, let me know (send a message, and i'll send it to you directly).

I don't think it matters what your "BMP" or MFP or anything says. are you feeling run down? If so, give yourself a little break... Do you feel like you want to do something more than lose the weight you are now? If you feel great while losing the weight you are now, you should feel great about it!!! If you feel like you need to eat a thanksgiving feast once you've gotten over whatever hump your'e trying to get over, you should scale it back so its sustainable. I got really into working out (yoga, eliptical, running, climbing, rugby, swimming, everything! anyways, I too started to freak out because I was loosing 2-3 lbs a week... but I was talking cereal to bed when i was REALLY hungry at night , and didn't have a bad "relapse" period, because It fit into my normal life. You are in risk if you start something unsustainable- either in diet or exercise. If you are loosing weight, and feeling greater and greater by the day, play on!!!

Hi, so I have been on here since January 1 of this year (yes, a resolutioner) and have lost 26lbs. I am set at a sedentary lifestyle, with wanting to lose the recommended 1 lb per week. I workout when I can, but that could mean several times a week or not at all. But I do eat back most, if not all, of my exercise calories. Currently, I am at 1400 cals a day, as set by MFP. It started higher, but as I lost MPF lowered it.

I am glad that I am losing, but I am worried that its happening too fast. I just looked up my BMR here and its 1507 cals a day. Is it okay that MPF has me under that, or should I up my calories?

I feel like I eat enough and have energy. It is working and I am happy with my loss. While I am not complaining, if this is unhealthy, I would want to fix it.

It's not unhealthy, but perhaps unwise, and slower, because in general that means your BMR is NOT really 1507, not if you have been netting at 1400 constantly for awhile and not hungry anymore.
At least eating back exercise has kept it that high - smart girl.

Now, that is only a difference of 100 a day, so not bad at all. Though, if you have been exercising and improving muscle, your potential BMR could be higher than estimated at this point.
So you could be missing out on more than 100.

And the problem is more that with slower metabolism - all your daily activity is actually burning less calories than it could be.
So what could be 1507 * 1.25 (sedentary) = 1883 - 1507 = 376 activity calories
Is really 1400 * 1.25 = 1750 - 1400 = 350 activity calories.
So a potential 26 daily or 182 a week. Not bad for missed potential. The inaccuracy in your exercise calories estimates and food calories is probably more than that.

As you have discovered, you actually lose more than 1 lb a week, which means your activity level is NOT really sedentary, but slightly above that multiplier. So that is great.

If you would like to try netting at the other side of your BMR for a couple weeks (it would be easier sliding into goal weight with full burning BMR), here's how you can setup MFP so stuff is still automatic.

Settings - Diet/Fitness profile
Change activity level to Lightly Active (which is 1.35 instead of 1.25)
Keep goal as 1lb weekly.

That should then set your daily net goal to 1535, just slightly above your current BMR.