Written by Cesare Attuoni
8th Mar 2023 • 8 minute read

Smoking and cigarettes have many serious negative effects on your health. The NHS reports that smoking is responsible for nearly 80,000 preventable deaths every year in England alone — making it the biggest cause of preventable death in the country. Statistics also show that 1 in 2 smokers will die from a smoking-related disease. 

Tobacco cigarettes

What’s inside a cigarette?

Research shows that cigarettes release over 5,000 harmful substances when they burn. The three main components are carbon monoxide, tar, and nicotine.

Carbon monoxide
Carbon monoxide is a poisonous gas that has no smell or taste. When it enters your bloodstream, your blood can’t carry oxygen. This forces your heart to work harder and will stop your lungs working properly. The lack of oxygen can also cause your cells and tissues to fail and die — which can lead to heart disease and stroke. 

Tar is created when tobacco is burned. It refers to a mixture of substances that come out of cigarettes as smoke, but when inhaled it forms a sticky layer inside your lungs. Tar contains most of the cancer-causing particles (carcinogens) in tobacco smoke — increasing your risk of developing cancer. Short-term effects include a chesty cough and shortness of breath. Tar is also what causes the yellow stain on your teeth that you get if you smoke.

Nicotine is a poisonous chemical that increases your heart rate. It’s also incredibly addictive and is responsible for the feeling of relaxation when you smoke.

Cigarettes also contain additives that flavour the cigarette, help the tobacco last longer, and make the smoke easier to inhale.

Tobacco cigarette split in half

How does smoking affect your heart health?

The carbon monoxide and nicotine in cigarettes increase your heart rate, making your heart work faster. Long-term, this puts a strain on your heart — making it more vulnerable to conditions like coronary heart disease, heart attack, and stroke. Statistics from the NHS show that smoking doubles your risk of having a heart attack and coronary heart disease. 

But, it’s never too late to stop. Studies show that just one year after quitting smoking, your risk is reduced by half. And after 15 years, your risk of heart disease is similar to someone who has never smoked.

How does smoking affect your veins?

When you smoke, the chemicals in tobacco tar enter your bloodstream. This makes your blood thicker, making it more likely to clot. Tar also causes your arteries to narrow, meaning less oxygen reaches your organs. And your blood pressure also rises, causing your heart to work harder. Long-term, these combined effects make you more likely to have a stroke or heart attack. 

Within five years of quitting, your chances of suffering from a stroke is similar to that of a non-smoker.

How does smoking affect your stomach?

Smoking increases your risk of stomach ulcers and stomach cancer. It particularly increases your risk for cancers of the upper portion of your stomach —near your oesophagus (the tube connecting your mouth to your stomach). The rate of stomach cancer is about doubled in smokers.

It’s also linked to an increased risk of kidney cancer. 10 cigarettes a day increases your risk by 1.5 times (compared to someone who doesn’t smoke). 20 a day doubles your risk.

How does smoking affect your lungs?

Your lungs are the part of your body that cigarettes damage most (along with your heart and veins). Short-term, you might experience chesty coughs, colds, and bouts of wheezing. Long-term, you might develop serious conditions like lung cancer, pneumonia, and chronic obstructive pulmonary disease (COPD).

Lung cancer

As you inhale the chemicals from smoke, it damages the cells in your lungs. Your body tries to repair the damage, but over time this becomes more and more difficult. Eventually, this might cause your cells to act abnormally and lung cancer could develop — smoking causes 84% of deaths from lung cancer. Smokers are 25 times more likely to die from lung cancer than those that have never smoked. 


COPD is a name given to describe several lung conditions that cause breathing difficulties, which tend to get worse over time. This includes chronic bronchitis (inflammation of your airways) and emphysema (damage to the air sacs in your lungs). 

Early symptoms of COPD are what’s sometimes called a ‘smoker’s cough’ — phlegmy coughs and breathlessness. This is down to the narrowing of your airways, damage to lung tissue, and a buildup of mucus. 83% of deaths from COPD are caused by smoking.

How does smoking affect your skin?

Smoking reduces the amount of oxygen that reaches your skin, making it age quicker and giving it a dull and grey tone. It also stimulates the production of the enzyme that breaks down collagen (a protein that is essential for skin elasticity). This causes your skin to sag — leading to wrinkles. 

What’s the link between smoking and cholesterol?

Smoking also affects your cholesterol. The tar makes your LDL cholesterol (‘bad’ cholesterol) stick to your arteries, clogging them up. Cigarettes also lower your HDL cholesterol (or ‘good’ cholesterol). 

Does smoking cause diabetes?

Smoking increases your risk of developing type 2 diabetes by 30%. This is because the damage smoke causes to cells can lead to inflammation and oxidative stress — an imbalance between damaging free radicals and protective antioxidants. This is linked to an increased risk of having type 2 diabetes. 

Long-term smoking also leads to an increase in belly fat, another risk factor for type 2 diabetes. 

What does smoking do to your mouth and throat?

Smoking causes both superficial and serious damage to your mouth and throat. The tar in cigarettes stains your teeth yellow. It can also give you bad breath. 

More seriously, smoking increases your risk of cancer in your lips, throat, tongue, and oesophagus. 93% of all cancers found in the throat area are caused by smoking. 

How does smoking affect your fertility and reproduction?

Smoking and male health

Smoking damages all of your blood vessels. This includes the ones that supply blood to your penis, which can lead to erectile dysfunction (impotence) in males — when you can’t get or keep an erection. NHS statistics show that in the UK 120,000 males in their 20s and 30s are impotent as a direct result of smoking. 

Smoking might also damage sperm and decrease your sperm count. It might also increase your risk of testicular cancer.

Smoking and female health

Smoking also affects female fertility. Females who smoke have 72% the fertility of non-smokers. Smoking during pregnancy might lead to pregnancy complications — like premature birth, miscarriage, and stillbirth. It might also increase the risk of cot death by at least 25%. 

How bad is smoking 1 cigarette a day for you?

Put simply, the more you smoke, the more harm it does to your body. But even one cigarette a day increases your risk of heart disease and stroke. A recent study found that people who smoke one cigarette a day increase their risk of heart disease by 48% in men and 57% in women. In other words, to reduce your risk of heart disease, stopping smoking altogether is much more effective than just cutting down

The amount of years you smoke has a bigger impact on your health than the amount you smoke a day — for example, 20 a day for 40 years is worse than 40 cigarettes a day for 20 years.  

The NHS also reports that every 15 cigarettes you smoke will cause a mutation in your body –– mutations are how cancers start.

E-cigarettes and vaping 

What is vaping?

Electronic cigarettes (e-cigarettes) are a battery-powered alternative to smoking. They’re also known as vapes. They still release nicotine, but don’t release tar or carbon monoxide — two of the main harmful chemicals found in smoke. 

E-cigarette and cigarettes in hands

Is vaping better for you?

Because e-cigarettes are still so new, their exact effects on your body are still not known. Plus, some studies on the effects of vaping are funded by tobacco companies (who now also supply e-cigarettes). So their interpretation of the results might be biased. 

The UK government states that ‘e-cigarettes are around 95% less harmful than smoking’. This figure has been challenged by several scientists, but most agree that vaping is less dangerous than smoking. Sceptics of vaping do point out that comparing e-cigarettes to traditional ones is misleading. Smoking is universally accepted as one of the most damaging things you can do to your health. So even something that’s 95% less harmful, could cause significant damage to your long-term health.

The NHS mentions that vapes could still contain some of the potentially harmful chemicals found in cigarette smoke (but at much lower levels). 

What are the risks of vaping?

E-cigarettes contain various substances that could harm your body.

Firstly, there’s nicotine. Apart from being addictive, nicotine has also been shown to cause harm to the developing brains of young people. 

Secondly, the ultrafine particles in the aerosol can be inhaled deep into the lungs, and damage them. So can flavourings that use a chemical called diacetyl. 

Are non-smokers beginning to vape?

One concern with vaping is that young people or non-smokers might see it as a risk-free alternative to smoking. Experts all highlight that e-cigarettes do pose health risks. And shouldn’t be marketed to young people or non-smokers. 

In the UK, over half of the people that vape are ex-smokers. While 39.4% of vapers are people who smoke both traditional and electronic cigarettes. Only 6.1% of vapers are people who’ve never smoked traditional cigarettes. Also, according to a survey conducted in 2019, the main reason why ex-smokers and smokers vape is to try and quit (or not relapse). Studies also show that those who vape daily smoke a lot less than those who vape less regularly.  In summary, all evidence suggests that vaping and e-cigarettes are not risk-free. But, they might be a useful tool to help current smokers quit.