Hello,
It is the nicotine contained in cigarettes which is  an appetite suppressant.
Following are the reasons why a person gains weight on quitting smoking.
1....smoking can increase the body's metabolism (smokers' bodies have to work to remove the toxins from cigarettes)
2....smoking affects how you taste and smell food (people often rediscover the joy of food when they give up smoking)
3...some people put food into their mouths rather than cigarettes,as they have the habit of putting some or other thing in he mouth.

Just dont worry about it,as this shall settle soon with calorie reduction and exercises.
The benefits of quitting smoking are enormous and so just don't start smoking again.
Thanks

Hello and welcome to Healthcare Magic. Thanks for your query.

Other than nicotine (which can suppress appetite), the smoke from traditional cigarrettes often causes gastric irritation, hyperacidity and agstric ulcers. So, this can be another reason for the suppression of appetite. This is possibly the reason why you have an increased appetite after stopping traditional cigarrettes.

Another possibility is that electronic cigarrettes may contain a lower dose of nicotine than the traditional cigarrettes (and traditional cigarrettes come with varying doses of nicotine). So, it is possible that you may have been previously smoking a stronger dose of nicotine when you were having the traditional cigarrettes - and this present reduction in the nicotine levels could be causing a rebound increase in appetite and weight.

Wish you all the best.

Regards,
Dr. Jonas Sundarakumar
Consultant Psychiatrist