Smoking harms almost every organ in the body, causing disease and cancer. Smokefree.gov explains the negative health effects of smoking.
Brain
Become addicted
Nicotine from cigarettes is as addictive as heroin. Nicotine addiction is hard to beat because it changes your brain. The brain develops extra nicotine receptors to accommodate the large doses of nicotine from tobacco. When the brain stops getting the nicotine it’s used to, the result is nicotine withdrawal. You may feel anxious, irritable, and have strong cravings for nicotine.
Head and Face
Ears
Smoking reduces the oxygen supply to the cochlea, a snail-shaped organ in the inner ear. This can result in permanent damage to the cochlea and mild to moderate hearing loss.
Eyes
Smoking causes physical changes in the eyes that threaten your eyesight. Nicotine from cigarettes restricts the production of a chemical necessary for you to be able to see at night, which can cause night blindness. Smoking also increases your risk of developing cataracts, glaucoma, macular degeneration and dry eye syndrome.
Mouth
Smoking takes a toll on your mouth. Smokers have more oral health problems than non-smokers, like mouth sores, ulcers and gum disease. You are more likely to have cavities and lose your teeth at a younger age. You are also more likely to get cancers of the mouth and throat.
Face
Smoking causes your skin to be dry and lose elasticity, leading to wrinkles and stretch marks. Your skin tone may become dull and grayish. By your early 30s, wrinkles can begin to appear around your mouth and eyes, adding years to your face.
Heart
Stressed heart
Smoking raises your blood pressure and puts stress on your heart. Over time, stress on the heart can weaken it, making it less able to pump blood to other parts of your body. Carbon monoxide inhaled from cigarette smoke also contributes to a lack of oxygen, making the heart work even harder. This increases the risk of heart disease and heart attacks.
Sticky blood
Smoking makes your blood thick and sticky. The stickier the blood, the harder your heart has to work to move it around your body. When your blood is sticky it is also more likely to form blood clots that block blood flow to your heart, brain and legs. Over time, thick, sticky blood damages the delicate lining of your blood vessels. This damage increases your risk for a heart attack or stroke.
Fatty deposits
Smoking increases the amount of cholesterol and unhealthy fats circulating in the blood, leading to unhealthy fatty deposits. Over time, cholesterol, fats and other debris build up on the walls of your arteries. This buildup narrows the arteries and blocks normal blood flow to the heart, brain and legs. Blocked blood flow to the heart or brain can cause a heart attack or stroke. Blockage in the blood vessels of your legs could result in the amputation of your toes or feet.
Lungs
Scarred Lung
Smoking causes inflammation in the small airways and tissues of your lungs. This can make your chest feel tight or cause you to wheeze or feel short of breath. Continued inflammation builds up scar tissue, which leads to physical changes to your lungs and airways that can make breathing hard. Years of lung irritation can give you a chronic cough with mucus.
Emphysema
Smoking permanently destroys the tiny air sacs in the lungs that allow oxygen exchange. When enough air sacs are destroyed, the disease emphysema develops. Emphysema causes severe shortness of breath and can lead to death.
Cilia
Your airways are lined with tiny brush like hairs, called cilia. The cilia sweep out mucus and dirt to keep your lungs clear. Smoking temporarily paralyzes and sometimes kills cilia. This makes you more at risk for infection. Smokers get more colds and respiratory infections than non-smokers.
DNA
Cancer
Your DNA, that acts as an “instruction manual” for cell growth and function. Every puff of a cigarette causes damage to your DNA. When DNA is damaged, the “instruction manual” gets messed up, and the cell can begin growing out of control and create a cancer tumor. Your body tries to repair the damage that smoking does to your DNA, but over time, smoking can wear down this repair system and lead to cancer (like lung cancer). One-third of all cancer deaths are caused by tobacco.
Stomach and Hormones
Belly
Smokers have bigger bellies and less muscle than non-smokers. As a smoker, you are more likely to develop type 2 diabetes, even if you don’t smoke every day. Smoking also makes it harder to control diabetes once you already have it. Diabetes is a serious disease that can lead to blindness, heart disease, kidney failure, and amputations.
Lower estrogen levels
Smoking lowers a female’s level of estrogen. Low estrogen levels can cause dry skin, thinning hair and memory problems. Women who smoke have a harder time getting pregnant and having a healthy baby. Smoking can also lead to early menopause, which increases your risk of developing many diseases.
Erectile Dysfunction or Infertility
Smoking increases the risk of erectile dysfunction—the inability to get or keep and erection. Toxins from cigarette smoke can also damage the genetic material in sperm, which can cause infertility or genetic defects in your children.
Blood and Immune System
High white blood cell count
When you smoke, the number of white blood cells (the cells that defend your body from infections) stays high. This is a sign that your body is under stress—constantly fighting against the inflammation and damage caused by tobacco. A high white blood cell count is like a signal from your body, letting you know you’ve been injured. White blood cell counts that stay elevated for a long time are linked with an increased risk of heart attacks, strokes, and cancer.
Longer to heal
Nutrients, minerals, and oxygen are all supplied to the tissue through the blood stream. Nicotine causes blood vessels to tighten, which decreases levels of nutrients supplied to wounds. As a result, wounds take longer to heal. Slow wound healing increases the risk of infection after an injury or surgery and painful skin ulcers can develop, causing the tissue to slowly die.
Weakened immune system
Cigarette smoke contains high levels of tar and other chemicals, which can make your immune system less effective at fighting off infections. This means you’re more likely to get sick. Continued weakening of the immune system can make you more vulnerable to autoimmune diseases, like rheumatoid arthritis and multiple sclerosis. It also decreases your body’s ability to fight off cancer!
Muscles and Bones
Tired muscles
When you smoke, less blood and oxygen flow to your muscles, making it harder to build muscle. The lack of oxygen also makes muscles tire more easily. Smokers have more muscle aches and pains than non-smokers.
More Broken Bones
Ingredients in cigarette smoke disrupt the natural cycle of bone health. Your body is less able to form healthy new bone tissue, and it breaks down existing bone tissue more rapidly. Over time, smoking leads to a thinning of bone tissue and loss of bone density. This causes bones to become weak and brittle. Compared to non-smokers, smokers have a higher risk of bone fractures, and their broken bones take longer to heal.