Smoking can cause fatal diseases such as pneumonia, emphysema and lung cancer.Smoking causes 84% of deaths from lung cancer and 83% of deaths from chronic obstructive lung disease, including bronchitis.
There are usually no signs or symptoms in the early stages of lung cancer, but many people with the condition eventually develop symptoms including:
a persistent cough
coughing up blood
persistent breathlessness
unexplained tiredness and weight loss
an ache or pain when breathing or coughing
Cigarette smoke contains over 4,000 chemicals, including 43 known cancer-causing (carcinogenic) compounds and 400 other toxins. These cigarette ingredients include nicotine, tar, and carbon monoxide, as well as formaldehyde, ammonia, hydrogen cyanide, arsenic,
Nicotine is highly addictive. Smoke containing nicotine is inhaled into the lungs, and the nicotine reaches your brain in just six seconds.
Nicotine in small doses acts as a stimulant to the brain. In large doses, it's a depressant, inhibiting the flow of signals between nerve cells. In even larger doses, it's a lethal poison, affecting the heart, blood vessels, and hormones. Nicotine in the bloodstream acts to make the smoker feel calm.
smokers often suffer shortness of breath and nagging coughs. They often tire quickly during physical activity. Some other common short-term effects include decreased sense of smell and taste, premature aging of the skin, bad breath, and stained teeth
Smoking also damages the arteries. This is why many vascular surgeons refuse to operate on patients with peripheral artery disease (poor blood circulation in the arms and legs) unless they stop smoking. And male smokers have a higher risk of sexual impotence (erectile dysfunction) the longer they smoke.
About half of the people who keep smoking will die because of it
In the United States, tobacco causes nearly 1 in 5 deaths, or about 480,000 premature deaths each year –almost half a million in the US alone. Smoking is the single most preventable cause of death in world.