Quit smoking: know your enemy

If you want to stop smoking, it helps to understand just how the addictive substance in tobacco, nicotine, gets a hold on you. When you inhale from a cigarette, a hit of nicotine enters your brain within 10 seconds. That is faster than the entry of almost any other substance and helps to give nicotine its powerful grip.

• Smoking feels good because nicotine is a stimulant. It can make you feel calmer, more energized and more mentally alert. By prompting release of the body's own feel-good chemicals, called endorphins, it can give you a mood boost and lift depression.
• These effects are only temporary, however. To sustain them, you need regular doses of nicotine, and after a while the brain adapts, lowering your natural energy and mood levels.
• So the consequence is that you need to smoke to feel "normal" — and, when you try to quit, you are hit hard by nicotine-withdrawal symptoms including anxiety, depression, impaired concentration and tiredness.
• Tobacco plants produce nicotine as a chemical defense against being eaten by insects. In other words, nicotine is a natural insecticide. So, when you smoke, remind yourself that you are taking in a toxin that, drop for drop, is more deadly than strychnine, arsenic and the venom of the diamondback rattlesnake.

Unfortunately, not inhaling makes little difference. Nicotine can be absorbed through the membranes that line the mouth as well as those in the lungs.

• The short answer is no.
• Any reduction is better than none, but as long as you continue to smoke you remain at risk.
• Even smoking just one to five cigarettes a day increases your risk of a heart attack by 38 per cent. Smoke more, and your risk rises in direct proportion to the number of cigarettes you smoke.
• If you are a two-pack-a-day smoker, your risk is increased by a staggering 920 per cent.
• Low-tar brands contain similar levels of tar and nicotine to normal brands; the main difference between the two types lies in the filter.
• But research shows that people who smoke low-tar cigarettes smoke harder and more frequently to satisfy their nicotine craving.
• According to one study, low-tar smokers ended up inhaling about 80 per cent more smoke than those who smoked normal brands and had similar levels of cancer-causing chemicals in their blood.