Smoking can dull your appetite, but this doesn't mean you will lose weight if you start. Giving up smoking doesn't mean you automatically put on weight either. People giving up often find they are tempted to reach for the fridge instead of a cigarette but choosing low fat healthy snacks, or finding something active to do instead, will help avoid any extra pounds. If it's looks you're concerned about, remember that smoking can have unpleasant effects on your skin too, causing dryness, wrinkles and a dull complexion. I like the feeling.
Many smokers say they enjoy smoking.
This is partly because of the effect of nicotine on the central nervous system. Also part of the enjoyment is probably linked to relieving withdrawal symptoms. Smokers' bodies get used to nicotine and if they don't smoke they feel a hunger for it. Relieving that hunger by smoking feels good in the same way that drinking water feels good when you are thirsty. There are likely to be times when you think about smoking - and let's face it, getting sick when you're older is probably the last of your worries right now.