I did the low-carb insanity for 2 years in order to lose 100 lbs of fat. I would estimate my daily net caloric intake (calories in - calories burned working out) was about 1,850-2,000. Usually I would eat about 2,500 and train to lose about 600 with weights and cardio. I went from about 275 lbs to 185 lbs (100 lbs of fat - 10 lbs of muscle gained = 90 pounds lost overall). I saw very little progress re: hypertrophy, gaining 10 lbs of muscle in 2 years is nothing to write home about.
If you want to get bigger, but with muscle instead of fat, (and I think that's what you're asking given that you refer to your body size), you will need to eat and train for hypertrophy. Strength gains can come with very little hypertrophy, believe it or not. I've seen guys who weigh 135 lbs and look skinny in a t-shirt come in and bench 200+ pounds in perfect form.
In my experience, low-carb diets work generally because they are low-calorie diets. It's easy to stay below 2,000 calories a day when all you eat is chicken, turkey and vegetables.
If you want to get huge, you need to eat huge and train huge. When I flipped my diet I gained 15 lbs of muscle in one year and all my 1-rep maxes went through the roof. I started training with much more emphasis on bigger weights (4-6 rep ranges), I went from 50/50 weights/cardio to 90/10 weights/cardio. Listen to this part: I also started eating 3,300 calories a day. It wasn't planned, but I got tired of waking up in the middle of the night with hunger pangs. I just kinda listened to my body. As soon as I did that, I started seeing tremendous gains in both strength and hypertrophy.
I wish I'd have known about T-Nation then, because trying to lift heavy while eating low calorie was an exercise in stupidity =). I guess I learned it the hard way (trial and error, trying to decode why I was getting hunger pangs at 3 AM). I guess we're all beginners in our own ways.
A food log is a good idea but a bit too much of a hassle. I just eat the same things pretty much day in day out, week day or week-end.
In order to up my calorie intake, I re-introduced whole eggs, red meat (I like horse, it's much leaner than beef and has 2x the iron per serving), fruits, starchy potatos, salad dressing, whole milk, and tons of healthy fat in the form of nuts, nut butter, olive oil, avocado. Believe it or not, I haven't even gained an inch on my waist (as a former fatso, I monitor it daily!), but I look much more muscular now.
The first 4 months I ate that, I think I put on about 5 lbs of muscle (i.e., half of what I put on in the preceding two years) and my lifts all exploded. My squat 1-rep-max doubled! Gains are slower now, but when I am trying to get bigger I usually eat 2,700-3,600 calories a day. Some guys at my gym are at 4,000+.
Here is an article I find useful:
If you want to get bigger, you will have to do it with the expectation of putting on some fat. This is because you will want to avoid a caloric deficit at all times.