I went to a personal trainer at my gym recently, and during part of my health assessment, we talked for almost an hour about what types of food to eat and how much to eat. I already have a lot of good habits going - lower carbs, no processed carbs, no corn syrup, higher lean proteins, lots of veggies. One thing that stuck out to him when reviewing my food journal though was that I do not eat enough.

He recommended based on my lifestyle, body size/structure, fitness routine, etc a diet of approximately 1588 calories. I eat about 1100-1200. To give you some background history, I have a history of disordered eating and crash dieting, but I've been healthy for a long time. This has slowed my metabolism tremendously.

But, I figure, what the ****? I'll give it a shot. I upped my calories slowly to 1500-1600. I started with 1200-1300 and worked up. Since increasing my calories, I have put on several pounds. I never go over the alloted calories, work out just as hard, and eat similar foods to what I was previously eating.

I'm panicking, because I don't want to blatantly ignore my trainer, but this is not working for me at all.

What would you do?

I think 1100-1200 is not enough. I'd suggest you do about 1300-1400 for a bit and see if that helps. I'm sure your trainer will understand if you don't feel comfortable with the amount he has suggested. There are some people who just need to eat less, regardless of what the BMR calculators say. If you see that after about 2 weeks, you're still not losing, then I'd say drop it a bit more but I would suggest you don't go less than 1200 if you can help it.

Also, I'd like to add that the few pounds gain could be water retention from the fact that you're working out with the trainer and your muscles are repairing. Just a thought though.

I wouldn't panic just yet. Your body has spent how long at 1100-1200 calories? It's gotten used to getting by with so few calories. When it finally gets the calories it needs, it stores them for a little while because it thinks it might be "starved" again. Obviously you are not starving, I'm just referring to the term "starvation mode" that gets talked about often here at 3FC.
I've heard your body does get used to the increased calories after a while and starts to lose weight again.
How long have you been eating the increased calories? Can you also post your height and current weight?
Again, I'm not a dr., I'm just spitting back what I keep seeing people talk about here. Others, please feel free to correct me!

if you decide to up your calories, I would do it slowly, not all at one time

Thanks for all the feedback so far, guys! I spoke with him initially about calories a little over two weeks ago. I started eating slightly higher Tuesday 2 weeks ago, and I have been working my calories up since then

Right now, I'm about 138 and 5'4. I typically weigh around 120 (and did until last summer), and then life happened and I put on a lot of weight in a short period of time. I started this journey into losing weight at roughly 170 pounds. I've been eating about the same (1100-1200 calories) since February, trying to get back to normal. :-)

As someone has already said, when you consume very low calories (I've heard this number vary from being 1200 to under your BMR depending on what study its from) your body goes into starvation mode, essentially it changes some of the basic ways it operates and lowers your overall requirements by approx 30% (Example. Someone who would normally require 2000 to maintain now requires 1400). Its fixable, by increasing calories and letting your body know its not starving (eating regularly, healthy meals), however, you may put on a little weight for the first couple weeks while waiting for the light bulb to go on internally.

ALSO, Your muscle weighs more then fat. You say you have gained a few pounds these could be from muscle and water retention due to weight training.

Overall, I'd recommend going with 1400 calories, talking to your trainer, and using measurements of your B/W/H (get a tape measure)

How much do you exercise? Do you do weight training?

My gut is that 1100-1200 is too low, especially if you exercise, especially if you lift weights. I think you need to give it more than 2 weeks. Anything could be going on to put you up a few pounds. Last week I gained four pounds between Friday and Monday (and lost them again by today, Thursday).

Also, you look young in your pic. If you are young, you need more calories.

When you say your metabolism is low -- have you actually had it tested? I read somewhere that while loads of people say they have slow metabolisms, it is actually very rare. I understand you have a history that could affect your metabolism, but don't assume it has.

Lastly, how closely do you count your calories? Do you weigh and measure? Before I bought a scale I did a lot of "eyeballing" and later it became obvious that I was overestimating my calories on a lot of foods, especially meats, so I was eating a bit under my target. If you are by any chance overestimating your calories at 1100, you could really be undereating.

and good luck with finding your sweet spot!

I'd give it a little more time as well to let your body adjust to losing at the higher calorie mark. BUT, if you continue to gain, there's no reason why you can't go back down to 1200 (maybe stick with that minimum though). Personally I think 1200 is a fine calorie intake, it's what I do and I'm never hungry. If you're losing weight on 1200 calories and you feel energized and you're eating the right things (which is seems like you are), then why fix something that isn't broken?