Is it true that smoking causes cancers other than lung cancer?
Smoking is causally linked to at least fifteen cancers outside the lung; quitting smoking reduces that risk, and the sooner you quit, the greater the benefit.
Smoking does indeed cause a large number of cancers outside the lung. A causal relationship has been established for cancers of the mouth and throat, the larynx, the nose and sinuses, the oesophagus, the stomach, the pancreas, the liver, the bile ducts, the colon, the kidneys, the ureters, the bladder, the cervix and the ovaries, as well as for leukaemia (a cancer of the blood). Up to 30% of all cancer deaths are attributed to tobacco smoking.
The risk of cervical cancer in current smokers is more than three times as high as in non-smokers. Both large observational studies and a genetic analysis support the conclusion that this is a causal relationship, not merely a coincidence or a side effect.
Breast cancer also occurs more frequently in women who smoke. Several large prospective studies show a consistently elevated risk: roughly 10 to 13% higher than in non-smokers. This is a relatively small increase, and whether it is entirely causal has not been established beyond doubt. With second-hand smoke (passive smoking), the elevated risk is smaller and the uncertainty is greater.
Smoking in combination with alcohol is particularly dangerous: the two risk factors reinforce each other, causing the cancer risk to multiply compared with smoking or drinking alone.
Quitting smoking demonstrably reduces the risk of all these cancers. The longer you have already been smoke-free, the greater the benefit. It is therefore never too late to quit, even if you have been smoking for many years.
Claims are based on two broad review articles (PMID 33735927, 36691379), a meta-analysis of 27 prospective studies on breast cancer (PMID 26546245), and a large observational study with Mendelian randomisation on cervical cancer (PMID 41062422).
Can long-term inflammation in your body cause cancer?
Prolonged inflammation is one of the most robustly supported risk factors for cancer. Well-known causes such as smoking, substantial obesity, and certain infections are modifiable, so addressing them concretely lowers your risk.
Does sitting a lot increase my risk of cancer, even if I exercise?
Sitting a lot increases your risk of certain cancers, even if you exercise. In addition to moving regularly, try to reduce your sitting time itself, because the two only partially compensate for each other.
Does being overweight increase my risk of cancer, and if so, which types?
Excess weight increases your risk of at least 13 types of cancer, including uterine, colorectal, breast and liver cancer. Losing weight reduces that risk, although it remains unclear whether all methods of weight loss are equally effective for immune defence against cancer.
Does eating a lot of sugar increase my risk of cancer?
Drinking large amounts of sugar-sweetened beverages is associated with a noticeably higher risk of certain cancers, particularly early-onset colorectal cancer and liver cancer. The association is observational, but consistent enough to make reducing soft drinks and fruit juice a concrete point of attention.
Does poor sleep increase my risk of cancer?
Poor sleep, and certainly untreated sleep apnoea, is associated with an increased cancer risk, but it has not yet been proven that sleeping poorly causes cancer. Have sleep apnoea checked if you have symptoms, and try to maintain a regular sleep schedule.
Does having type 2 diabetes increase your risk of certain cancers?
Type 2 diabetes increases the risk of several cancers, including liver, pancreatic, uterine and colorectal cancer. If you have diabetes, it is worthwhile to discuss with your doctor whether closer attention to early detection or lifestyle improvement is appropriate for you.