I too have experienced all symptoms listed on here, predominantly the bloating, constipation, abdominal pain after eating since i quit smoking 2 weeks ago. I am astonished that despite searching online where I concluded i may have signs of cancer!!!! and visiting the doctors where i feel i've been disregarded this is the only website that pinpoints the exact symptoms. Yesterday was my recent visit to the doctors and I asked her if my symptoms could be the result of stopping smoking and she categorically said "no". Any website/information pack on quitting smoking will list other symptoms but not any of the things discussed on here.....quite shocking.
I notice fruit, veg and pulses sit well with me and I have little or no symptoms as well as drinking water really helps. Anything outside of these foods e.g. meat, dairy, fatty foods, spicy, processed etc i have terrible abdominal pain within 15 mins of eating no matter how small, the bigger the portion the more the pain aftewards. I then have sharp pain in my back. I also experience headaches and feel i cannot concentrate which i do understand is from definitely smoking too. Everyone is different and it seems it depends on how long of a smoker you were in the past as to how severe the discomfort is when you quit. I smoked maximum 7 a day for 10 years (generally a social smoker so had most cigs on a night out) and although i get the symptoms mentioned above I'm still able to leave the house and get on with my day to day life, albeit very uncomfortable. I haven't yet gained weight but it has only been 2 weeks and to be honest i've been scared to eat due to knowing what was wrong with me before finding this page.
I cannot thank you enough to all those that posted and shared their experiences, extremely helpful as it doesnt seem to be common knowledge how much symptoms can arise from quitting. If i had known this before i started smoking i would never have touched the rancid cigarette.