Ahhh, weight gain, weight loss. Here's what I've learned thru a lot of years of testing every frigging diet known to man. Several years ago, before I was realized my situation with celiac disease, my weight gain (about 30 lbs over my ideal 130 lbs which I weighed ALL my life with no problem) was bugging me. I did a strict Body for Life program for maybe 10 weeks, fairly true to the program. I ate what was suggested (including small amounts of bread) and exercised vigorously (weights and cardio) 6 days a week, an hour each day. I dropped about 20 lbs, although I didn't reach my goal. A couple of years later I decided to do Atkins, and was very strict with its induction program for a good 6 to 7 weeks. I lost a LOT of weight, got almost to my goal with no effort, and in the process, realized how wonderful I felt doing Atkins. Looking back, I now realize it was because I was eating NO GRAIN!!!! and virtually no dairy other than about an ounce of hard cheddar cheese a day. Also...no sugar, no fruit. Just meat, salads, moderate veggies, an ounce of cheese a day, lots of water. I was never a big meat eater, but was shocked at how fabulous I felt on this unfamiliar diet. When you keep carbs low like this, you do not have any sugar or junk cravings, either. I lost more weight more easily this way than anything else, period!
Well, a few years passed, I put back on about 15 of those lost pounds over time (thru sloppy eating and little to no exercise), and then started trying to lose weight again....various programs, nothing worked, and no matter how moderate my calorie level was and how much I exercised, I didn't lose a single pound and didn't lose all that much fat. Really frustrating.
So for myself, I've realized it MOSTLY comes down to your food intake, and I realized that I can't lose weight when eating a lot of sugar, carbs in general, dairy, even a lot of fruit. When I first went gluten free I started eating and "testing" all the gluten free goodies out there, which I soon noticed frequently had SUGAR as the first, main ingredient. These things are incredibly high carb, high sugar. While eating all this stuff, I continued to have a very upset digestive system. I think I didn't handle the various starchy flours or all the sugar. And I realized that I wasn't eating that way before celiac....I knew I couldn't eat all that sugar stuff without gaining weight....so why was I eating it now?
Well, this is rambling, but ultimately, I and I suspect many others as well, will not lose weight either eating gluten OR gluten free if I/we don't eat very carefully....good clean protein, good vegetables (but not much if any potatoes or rice or corn), very little in the baked goods category, and limited dairy. Little to no sugar. And finally, realistic PORTION CONTROL. And reasonable physical activity on a daily basis....could be as simple as walking. I don't think I have some weird unique body composition....I've always been pretty healthy aside from my digestive woes, and was slim my whole life until about 15 years ago when I put on this 20 to 30 lbs which I've been unable to completely lose. There's no magic pill, no magic program, just the right foods in the right amounts and reasonable physical activity every day.
Finally....you have to do these things and keep at it despite what we will always deem a "too slow rate of loss." The the turtle wins the race, and I've learned to accept that weight loss will be slow but steady when I do the right things. Every day you do the right things is a step towards your goal weight, simple as that. You are either moving towards your goal or away from it, depending on your choices for the day!