How Does Smoking Relate to CVD?
Smoking affects your health in a big way. The many harmful chemicals in cigarettes cause damage to nearly every organ in your body, including your heart, blood vessels, mouth, eyes, lungs, bones, reproductive organs, bladder, and digestive organs. This is why smoking causes so many deaths — more than 37,000 Canadians will die prematurely each year from tobacco use and almost 6,300 non-smokers will die from exposure to second-hand smoke.
The nicotine in smoke causes the arteries of your heart to narrow. The carbon monoxide released from cigarettes damages the walls of your arteries, encouraging fat to build up on artery walls.
- Raises your LDL (lousy) cholesterol
- Lowers your HDL (healthy) cholesterol
- Speeds up your heart rate
- Raises your blood pressure
- Makes your heart work harder
Any amount of smoking — light, occasional, or second-hand — is dangerous and likely to cause damage to your cardiovascular system. The harmful chemicals from a cigarette can negatively affect the condition and functioning of your heart and blood vessels. For example, nicotine increases your heart rate, while carbon monoxide (a toxic gas) replaces oxygen in your red blood cells. Together, these affect the normal function of your heart, eventually making it work harder. Over time, smoking also causes plaque to build up in your arteries, a decrease in the oxygen in your blood, and increased blood pressure.1, 4 What you face as a smoker if you continue to smoke includes the following:
- On average, smokers live 10 fewer years than non-smokers.
- Smokers have double the risk for cardiovascular disease compared to non-smokers.
- Smokers are up to four times more likely to experience sudden cardiac death than non-smokers.
- Smoking causes about 10 per cent of cardiovascular disease overall, and it’s especially dangerous for women. Being a smoker puts younger women at 60 per cent higher risk for heart disease than men of the same age, effectively cancelling out the protection most young women seem to have from heart disease.
- Smoking damages the heart, contributes to high blood pressure and leads to the buildup of fatty substances that can narrow and block arteries, leading to hypertension and cardiovascular disease. When an artery becomes completely blocked, the result is usually a heart attack. In a long-term study of 12,000 women, even smoking just one to four cigarettes a day doubled the risk of dying from a heart attack significantly. Ask your doctor to connect you with resources to help you quit smoking for good.
Smoking Is Not A Habit, It's An Addiction
Quitting smoking is hard, but it’s not impossible. Every year, thousands of people go smoke-free. Quitting smoking is the most powerful thing you can do to reduce your risk for heart disease. Because smoking is so highly addictive, quitting is extremely difficult and requires persistent effort and help from others.
The decision to quit smoking is influenced by your beliefs about the benefits of quitting and by the physical dependence of smoking. Many smokers attempt to quit several times before succeeding. When you are ready to quit, a variety of proven methods are available to increase your chances.
Your quit plan should include a range of strategies to address the various aspects of smoking. Smoking is an addictive process that becomes a learned behaviour, and it is supported in three ways:
- Physical Dependence
Nicotine is a powerfully addictive drug. Once inhaled through cigarette smoke, nicotine is rapidly absorbed into your bloodstream. Your body quickly learns to crave its presence. When you stop smoking, the amount of nicotine in your body drops and you may experience irritability, difficulty sleeping, changes in appetite, and fatigue. Reactions vary from person to person. These are normal signs of recovery from nicotine.
- Behavioural Conditioning
Smoking behaviours are repetitive and, over time, can become unconscious habits reinforced by where you smoke, the activities you engage in while smoking, and the emotions you feel when you have a cigarette. Behaviours that are repeated hundreds of thousands of times each year add to the difficulty of quitting.
- Social Aspects
Many people smoke in the company of friends and family. The social aspects of nicotine dependence are difficult to overcome. This is because once you quit, you are still exposed to the social situations that remind you of smoking. Nevertheless, you can learn to handle social situations so that they are not triggers for smoking.
Inside a Cigarette
To better understand why smoking is so bad for your health, it helps to know what’s in a cigarette. The three main components of a cigarette are nicotine, tar, and carbon monoxide. Each cigarette contains tobacco and numerous chemicals, including toxic substances. Tobacco naturally contains nicotine, notorious for its highly addictive properties. In addition to nicotine, smokers and those around them are exposed to more than 4,000 chemicals. Hundreds of these are toxic and more than 50 can cause cancer.
- Butane found in lighter fluid
- Cadmium found in batteries
- Stearic acid found in candle wax
- Toluene found in industrial solvent
- Nicotine found in insecticide
- Ammonia found in toilet cleaner
- Methanol found in rocket fuel
- Methane found in sewer gas
- Acetic acid found in vinegar
- Carbon monoxide
- Arsenic found in poison
Nicotine is why it’s so hard to quit smoking. Found naturally in tobacco, it is a highly addictive drug that is absorbed in no more than four to seven seconds through the tissue that lines your nose and mouth. In this way, nicotine is fast-tracked to the addiction centre of the brain.
Nicotine alters your brain chemistry, changing the way you feel and act. It can make you alert and better able to concentrate because it releases the chemical dopamine in the brain. Dopamine also has the effect of increasing feelings of pleasure so that you associate smoking with positive sensations. Dopamine therefore strongly rewards smoking behaviour, making it highly likely you’ll continue smoking. Once you experience nicotine, as with other addictive substances, your body craves more of the drug. As your tolerance increases, you need to smoke more to avoid nicotine withdrawal symptoms.
It’s important to recognize that nicotine acts both physically and psychologically. The powerful physical addiction is created as nicotine rewards smoking behaviour by altering the brain, and the speed at which nicotine reaches the brain creates a strong association between smoking and the feelings it generates. Together, these mechanisms create a negative cycle that is extremely difficult to break.6
This video lecture explains the process of nicotine addiction (Mayo Clinic).
Smoking is associated with many health risks for both the smoker and those exposed to the second-hand smoke, causing significant damage to the entire body. Although no level of smoking is considered safe, smoking fewer cigarettes for a shorter period of time can reduce the damage. Any level of smoking can cause the following:
- Shortness of breath
- Worsening of asthma symptoms
- Respiratory infection
- Harm to pregnancy
- Lung cancer
- Cancers of the colon, mouth, throat, bladder, and cervix
- Emphysema and bronchitis
- Smoker’s cough
- Heart disease and stroke
- Complications during pregnancy that can lead to an underweight baby or premature death in infancy
- Digestive problems
- Compromised immune system — increased likelihood of flu and pneumonia
- Decreased vitamin C levels, causing wounds to heal more slowly
- Restricted circulation in the legs
- Macular degeneration (vision loss at the centre of the field of vision)
- Gum disease
- Tooth loss
- Raynaud’s phenomenon (fingers that turn white or blue in the cold)6 7
Dangers of Second-Hand Smoke
Second-hand smoke is the smoke from a tobacco product exhaled into the environment. It contains not only asbestos, arsenic, ammonia, and benzene but more carbon monoxide and tar than the smoke that is inhaled by the smoker. Because the harmful chemicals remain in the air long after the cigarette is smoked, non-smokers frequently in contact with second-hand smoke experience excessive coughing and are at risk of developing heart disease, lung cancer, emphysema, and chest infections — putting them at increased risk for premature death.
The smoke exhaled by the smoker tends to be more toxic than the smoke burning directly from the end of the cigarette. Therefore, those exposed to second-hand smoke are essentially inhaling the same chemicals as the smoker but with an increased sensitivity that comes with being a non-smoker.