Nicotine is the world's most powerful natural insecticide. Would you like to live in a field where they sprayed insecticide 20 times a day?
Well, you don't need to if you smoke 20 cigarettes a day....you are already putting insecticide into your lungs, arteries and brain all day long. Nicotine affects the neuromuscular system of insects causing them to go into convulsions and die.
For years it was thought that hypoxia/C02 was causing the arteries of smokers to clog up (especially the coronary arteries, which are very narrow to start with). There's no doubt hypoxia causes damage to the endothelium but a study in 2002 by Dr. Thomas Neunteufl from the University of Vienna in Austria, suggested the real culprit was nicotine:
Researchers administered 1 milligram of nicotine via a nasal spray or cigarette smoke to 16 healthy long-term smokers, and then used ultrasound to examine the endothelium after 20 minutes. Nicotine-containing nasal spray and cigarette smoke alike reduced blood flow inside the artery, the study found, with the cigarette smoke reducing blood flow only slightly more.
http://ffn.yuku.com/topic/12077/t/Nicot ... eries.html
Ironically, nicotine spray is recommended to smokers to help them quit.
Smoking 5 cigarettes a day doubles the risk of breast cancer in women. This can hardly be due to tobacco tar in the lungs! I believe nicotine is the main reason smokers have increased risk of cancer all over the body - throat, oesophagus, stomach, lungs (surprisingly, only 20% of smoking deaths is caused by lung cancer), liver, reproductive organs... no wonder 1 in 4 smokers dies in middle age.
If Dr. Neunteufl's findings are correct, it is likely to be nicotine that causes the arteries in the brain to narrow in smokers. Nearly as many smokers die from strokes as lung cancer. Surely it is nicotine entering the womb that causes so many birth defects, still births and infant mortality when the mother smokes in pregnancy.
gainsbourg