Eat below BMR?

I've been eating (or sticking as close to as possible) 1200 cals per day and I've lost 27.5kg / 61lbs in 14 months.
I guess it's a personal thing... do what works for you.

You can always eat the lower amount for awhile and see how you go, then increase it if it's not working for you? Good luck!

I've lost all my weight eating below my BMR. BUT I think this is the reason I have ended up low weight/high body fat. I'm going to try to net my BMR from now on & I have been netting close to it recently. I was just scared to eat more, but now I asked for some help from sum1 who looks amazing & I'm going to do it. Sum1 on here did a study on ppl how ate back their exercise cals and ppl who didn't. People who ate them back lost less muscle mass. Weight doesn't tell u every thing, doesn't tell u whether ur losing fat or muscle. Keep that in mind.

Hi,

I've seen a bit on here about how its bad to eat under your BMR. My current calorie goal is 1290, which is 500 under MFP's calculation of my TDEE as 1790. MFP calculates my BMR as around 1450.

So, I'm eating under BMR. But if I eat to BMR then I won't have a 500 deficit below my TDEE.

I'm a bit confused, should I be eating my BMR?

It has more to do with your energy availability, or net calories, in this case.

Your calorie goal is your net calories that you should reach after deducting exercise. If you were not to exercise, then eating the 1290 is fine. Note that a deficit includes the sum of restricting intake calories AND exercise calories. MFP's default deficit only considers, in your case, a 500 calorie deficit coming exclusively from eating 500 calories under TDEE. If you wish, and in your case I do, to stick with the 1 lb per week plan, then you need to eat an additional X amount of exercise calories so your net stays at 1290. If you were to exercise and burn off 300 calories, and do not eat an additional 300, you would create a 800 calorie deficit and, thus, be 300 under your goal (1290 - 300 = 990 net). That would be a huge 45% deficit below TDEE instead of a more sustainable yet high cut of 28%. Ideally, the less body fat you have to lose (the leaner you are), the less of a deficit you should create because the less calories from true fat you will actually use. We all have limits to how many calories from a lb of fat we can potentially burn, thus, it's no advantage to create an unnecessarily large deficit if it does not lead to more true fat loss.

FYI, woman of average weight and body fat percentage can lose potentially up to 2 lbs of true fat per month, or 0.5 lbs per week. Leaner people will expect slightly lower true fat loss whereas people the size of The Biggest Loser contestants can lose up to 8 lbs per month.

I personally have seen nothing scientific stating it's detrimental to eat below your BMR (if someone has some reputable studies, please send them my way). My net target is 1200, though I allow myself to go up to 1400 on non-workout days. On workout days, I eat anywhere from 1500 to 1900 to net my 1200. I've been doing this for 16 months now (target started around 1460 when I started and is now down to 1200 since I've lost so much weight) and had my RMR tested by the university hospital system in July. It was 1662, which is about 10% above online calculator estimates. Eating below my BMR (but eating back ALL exercise calories) has absolutely not affected my metabolism at all.

If you are struggling and think you should be losing more, I would suspect a counting issue. Either you're eating more than you realize (weigh everything, measuring is NOT accurate) or you're not burning as many calories exercising as you think you are.