Ughh

Are you drinking enough water and limiting sodium on most days? I know that my cheat day means I'm taking in a bit more sodium than I should so I retain water and the number on the scale goes up the next day. Also, are you taking measurements in addition to weighing yourself? Weight is a very rudimentary way of tracking fitness. You might have developed muscle weight also. A tape measure will give you a better idea about changes.

There's also the chance that you need to change up your workout intensity. How long have you been running 3 times a week? Is it the same distance and heart rate each time? If it is, maybe you need a new cardio routine.

Good job on the weight loss! You are probably stuck at that weight with that calorie intake and consistent exercise regimen. It sounds easier than it is, but changing your exercise regimen is probably the simple thing to do. Try to focus on intense bursts of activity in weight bearing exercises that you don't normally do (a proven burner). Combining exercises normally done as single motions with significantly lighter weights - squats and shoulder press for example - can be very effective, just think "explosive" when you move. Not knowing your conditioning level or possible injuries or weak spots (mine is the left shoulder) you may have, proceed with caution. If you want some ideas for training explosively, check out the guys who train for mixed martial arts fights. The lighter and middle weights are some seriously lean and fit people. Good Luck!

It sounds like your body metabolism has slowed, maybe as Bridgie says, 1400 cals is insufficient.
My question is this: do you still have body fat that you need to remove? Rigorous exercise produces muscle, hopefully replacing the fat you are losing, wt for wt. However, if you heart is elevated excessively during exercise, chances are you are not burning fat, rather using muscle tissue. Try some starvation exercise: ie run or exercise in the morning before eating, keeping the heart rate below125/130 bpm. Consume lots of water, keep a healthy attitude. Well done, you'll get there.

Have you entered your new weight into MFP? You need to if you want to get the correct calculations. Certainly every 5 pounds.

I also stall if my carbs for the week get over 50%, even if I'm in my calories.

Finally, yes, as you get closer, it gets slower. Keep at it. And congratulations!

It sounds like your body metabolism has slowed, maybe as Bridgie says, 1400 cals is insufficient.
My question is this: do you still have body fat that you need to remove? Rigorous exercise produces muscle, hopefully replacing the fat you are losing, wt for wt. However, if you heart is elevated excessively during exercise, chances are you are not burning fat, rather using muscle tissue. Try some starvation exercise: ie run or exercise in the morning before eating, keeping the heart rate below125/130 bpm. Consume lots of water, keep a healthy attitude. Well done, you'll get there.

Ah, no. Rigorous exercise does not produce muscle. Strength training helps to build muscle. As for heart rate, that is utterly wrong. The more your heart rate is up, the more calories you burn.

Buy a food scale and start logging your cheat days.

Hmm mactaffy84, you've missed the point, and my definition of rigorous fits with yours! Of course the higher the heart rate the calories burned, but the issue is where are these calories coming from??? High heart rates tend to burn muscle, not fat, given it is easier to breakdown and the body is asking for calories in a hurry. More work, slower heart rate, more fat burned. Cheers.

Sorry but muscle being used as fuel is a complete myth for all but people on a totally inadequate diet or extremely excessive exercise (certainly not an issue for the OP's routine). Otherwise all the world's athletes would have the least muscle!

The so called fat burning zone is thoroughly debunked.
It doesn't matter what heart rate you exercise at - the calorie balance at the end of the day is what is important.

OP - your diary is private. As you are in a plateau the most like explanation is that you are eating at maintenance calories.
Suggest you revisit your logging accuracy, weigh and measure everything you eat. Be really consistent for a few weeks and see what results you get.
The other side of the equation is how are you estimating your calorie burns? Assuming you are eating back exercise calories of course.

You have to eat at a calorie deficit to lose weight. Think about it, if your already eating at maintenance, why would you eat more? Try cutting back to 1200 calories, I bet you will lose weight!!

Congrats on the 40 whoop!

I'm in the same boat as this person:

I will not pretend to be an expert but in my own personal experience, my body will not release weight if I am not taking care of myself in other ways. If I am sleep deprived I cannot lose weight. If I am not drinking enough water I cannot lose weight. If I am not managing my stress levels I cannot lose weight. It does not matter how much run, work out, have perfected my eating habits. I have to set my body up for success.
Thats all Ive got!

If I don't take care of myself beyond diet everything goes freaking haywire!

I am at the exact same height and almost same weight(140-141) and have lost 35 pounds as well from my highest. But i know why i am not losing though I have slagged right now because i know i am at a healthy comfortable weight and it takes extra dedication and motivation to lose the last few pounds Give it all you have got, if you want it badly and it will happen! Count everything you intake, even cheat days and it will make more sense!
Good luck!