The benefits are almost instant. As soon as a person stops smoking their body begins to recover in the following ways:
After 1 hour
In as little as 20 minutes after the last cigarette is smoked, the heart rate drops and returns to normal. Blood pressure begins to drop, and circulation may start to improve.
After 12 hours
Cigarettes contain a lot of known toxins including carbon monoxide, a gas present in cigarette smoke.
This gas can be harmful or fatal in high doses and prevents oxygen from entering the lungs and blood. When inhaled in large doses in a short time, suffocation can occur from lack of oxygen.
After just 12 hours without a cigarette, the body cleanses itself of the excess carbon monoxide from the cigarettes. The carbon monoxide level returns to normal, increasing the body's oxygen levels.
After 1 day
Just 1 day after quitting smoking, the risk of heart attack begins to decrease.
Smoking raises the risk of developing coronary heart disease by lowering good cholesterol, which makes heart-healthy exercise harder to do. Smoking also raises blood pressure and increases blood clots, increasing the risk of stroke.
In as little as 1 day after quitting smoking, a person's blood pressure begins to drop, decreasing the risk of heart disease from smoking-induced high blood pressure. In this short time, a person's oxygen levels will have risen, making physical activity and exercise easier to do, promoting heart-healthy habits.
After 2 days
Smoking damages the nerve endings responsible for the senses of smell and taste. In as little as 2 days after quitting, a person may notice a heightened sense of smell and more vivid tastes as these nerves heal.
After 3 days
3 days after quitting smoking, the nicotine levels in a person's body are depleted. While it is healthier to have no nicotine in the body, this initial depletion can cause nicotine withdrawal. Around 3 days after quitting, most people will experience moodiness and irritability, severe headaches, and cravings as the body readjusts.
After 1 month
In as little as 1 month, a person's lung function begins to improve. As the lungs heal and lung capacity improves, former smokers may notice less coughing and shortness of breath. Athletic endurance increases and former smokers may notice a renewed ability for cardiovascular activities, such as running and jumping.
After 1-3 months
For the next several months after quitting, circulation continues to improve.
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