The immediate and long term benefits of stopping smoking

Within 20 minutes:
Your blood pressure, pulse rate, and the temperature of your hands and feet will all return to normal.

Within 12 hours:
Your blood oxygen level will have increased to normal and carbon monoxide levels will have dropped to normal.

Within 48 hours:
Damaged nerve endings have started to regrow and your sense of smell and taste are beginning to return to normal.

Within 72 hours:
Your entire body will test 100% nicotine-free and over 90% of all nicotine metabolites will now have passed from your body via your urine. You can also expect the symptoms of chemical withdrawal to have peaked in intensity. Your bronchial tubes are beginning to relax thus making it easier to breathe. Your lung capacity has also started to increase.

10 days to 2 weeks:
Your body has physically adjusted to again functioning without nicotine and the more than 3,500 chemical particles and 500 gases present in each and every puff.

2 weeks to 3 months:
Your heart attack risk has started to drop. Your lung function is beginning to improve.

3 weeks to 3 months:
Your circulation has substantially improved. Walking has become easier. Your chronic cough, if any, has likely disappeared.

1 to 9 months:
Any smoking related sinus congestion, fatigue or shortness of breath have decreased. Cilia have regrown in your lungs thereby increasing their ability to handle mucus, keep your lungs clean, and reduce infections. Your body's overall energy has increased.

1 year:
Your excess risk of coronary heart disease has dropped to less than half that of a smoker.

5 to 15 years:
Your risk of stroke has declined to that of a non-smoker.

10 years:
Your risk of death from lung cancer has declined by almost half if you were an average smoker (one pack per day).  Your risk of cancer of the mouth, throat and esophagus has now decreased.

15 years:
Your risk of coronary heart disease is now that of a person who has never smoked. Quitting helps stop the damaging effects of tobacco on your appearance including:

• Premature wrinkling of the skin
• Bad breath
• Stained teeth
• Gum disease
• Bad smelling clothes and hair
• Yellow fingernails

Kicking the tobacco habit offers benefits that you'll notice immediately and some that will develop gradually over time. These rewards can improve your day-to-day life immensely.

• Food tastes better.
• Your sense of smell returns to normal
• Ordinary activities no longer leave you out of breath (for example, climbing stairs or light housework)
The prospect of better health is a major reason for quitting, but there are others as well.

Cost
Smoking is expensive. It isn't hard to figure out how much you spend on smoking: multiply how much money you spend on tobacco every day by 365 (days per year). The amount may surprise you. Now multiply that by the number of years you have been using tobacco and that amount will probably astound you.
Multiply the cost per year by 10 (for the upcoming 10 years) and ask yourself what you would rather do with that much money.
And this doesn’t include other possible expenses, such as higher costs for health and life insurance, as well as the health care costs due to tobacco-related conditions.

Social Acceptance
Smoking is less socially acceptable now than it was in the past.
All workplaces now have smoking restrictions. Some employers even prefer to hire nonsmokers. Studies show smoking employees cost businesses more to employ because they are "off sick" more frequently. Employees who are ill more often than others can raise an employer’s need for expensive temporary replacement workers. They can increase insurance costs both for other employees and for the employer, who typically pays part of the workers’ insurance premiums.
Landlords may choose not to rent to smokers since maintenance costs and insurance rates may rise when smokers occupy buildings.
Friends may ask you not to smoke in their houses or cars. Public buildings, concerts, and even sporting events are largely smoke-free. Like it or not, finding a place to smoke can be a hassle.
Smokers may find their opportunities for dating or romantic involvement, including marriage, are largely limited to other smokers, who make up only about 1/4 of the population.

Setting an Example
If you have children, you probably want to set a good example for them. When asked, nearly all smokers say they don't want their children to smoke, but children whose parents smoke are more likely to start smoking themselves. You can become a good role model for them by quitting now.