This is a long post but it's one worth reading because it sums up my experience of low carbing since September.
For the people that are having trouble turning down food for politeness sake or because they are worried about people's reactions to saying you are low carbing, what I do in restaurants etc is say that I am coeliac (this might be true - I definitely have issues with wheat) and diabetic (this would be true if I continued to eat carbs - I was borderline pre-diabetic this time last year after eating mostly low GI carbs for many years). I used to just say that I was wheat intolerant and on a low carb diet and always found that people bent over backwards to accomodate me - I just say I'm coeliac and diabetic for simplicity's sake. It's a very British thing to not want to make a fuss but every place I've asked have been happy to do me a mix and match from the menu. If you see something like:
Steak, peas and chips
Salmon, broccoli and new potatoes
Chicken, spinach and pasta
Most places would be happy to give you Steak, broccoli and spinach if you just ask them.
As for depression and carbs. Last summer I had such bad depression that I was having a good day if the only constructive thing I did was have a shower - I managed this maybe twice a week. Citalopram made me better enough that I wanted to do something about the weight gain the depression had caused so I started low carbing and within about a month I had to halve my dose because I was bouncing off the walls.
My insomnia has also almost completely vanished. A good night for me used to be getting to sleep within an hour of lights out and now I get to sleep pretty much straight away most nights and an hour is a bad night. Previously a normal night was not getting to sleep until dawn and a bad night was not sleeping at all.
The other things that have improved are my flatulence, asthma and psoriasis which I think are all at least partly down to cutting out wheat. I used to be a very farty person which was quite embarrassing at times but now I only really fart if I've accidentally eaten something with wheat in it (it's very hard not to eat any wheat because it's in pretty much everything processed). My asthma has gone from me getting through a ventolin inhaler a month to not using it at all for several months. My psoriasis which is only around my nose has gone from being horribly red and inflamed the whole time to just when I'm stressed and even then not so bad.
There are probably other things that cutting out wheat/low carbing have helped that I just haven't put two and two together for yet.