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.
Yes, type 2 diabetes increases the risk of several types of cancer, and for some the risk is considerable. The most robustly supported association is with liver cancer: people with type 2 diabetes are more than three times as likely to develop it as people without diabetes. Pancreatic cancer, uterine cancer, colorectal cancer and breast cancer have also been consistently linked to diabetes, both through large observational studies and through genetically informed analyses. For colorectal cancer the increased risk is approximately 21 percent.
For gallbladder and bile duct cancer the observational evidence is also strong, although it is less clear here whether the association is causal. For kidney cancer, genetic analyses support a possible causal link. For stomach cancer, lung cancer and bladder cancer the risk is also elevated, but to a lesser degree and harder to separate from other factors such as smoking or excess weight. For lung cancer, smoking plays a confounding role, making it difficult to determine the portion of risk attributable purely to diabetes.
One exception: prostate cancer. Large prospective studies actually found a lower risk in men with type 2 diabetes. Why this is the case has not yet been explained well on a biological level.
An interesting pattern lies in the timing. The elevated overall cancer risk peaks around six to eight years after the diabetes diagnosis and then gradually declines. After fifteen years, cohort research found no more significant elevation in overall risk. This runs parallel to blood insulin concentrations: higher insulin levels in the early stage of diabetes appear to stimulate cell division, which is a plausible biological mechanism. If you also have other risk factors such as excess weight, smoking or physical inactivity, those risks add up: diabetes patients with several such factors also develop cancer at a younger age on average.
Cancer has now become one of the leading causes of death in people with type 2 diabetes, which makes the combination particularly relevant. If you have diabetes, discuss with your doctor whether additional screening or lifestyle-based risk reduction makes sense for you, especially if other risk factors are also present.
Based on a systematic review, multiple meta-analyses, large prospective cohort studies (including UK Biobank) and genetic analysis studies (Mendelian randomisation). The total body of evidence is large, but for some cancer types (bladder, stomach) the evidence is weaker or harder to separate from confounders.
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 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 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 working with pesticides increase your risk of cancer?
Working with pesticides is associated in multiple studies with an increased risk of several types of cancer, including bladder, bowel, and blood cancers. Avoiding unprotected contact is sensible, especially if you are pregnant or planning to become pregnant.
Does type 2 diabetes increase your risk of dementia?
Type 2 diabetes substantially increases the risk of dementia, and the younger you are at diagnosis, the greater that risk. Good blood sugar management and the choice of medication appear to be relevant; discuss this with your doctor if you have diabetes.
Does eating a lot of sugar give you type 2 diabetes?
Sugary drinks clearly and demonstrably increase your risk of type 2 diabetes. Sugar from solid food barely does. The biggest difference comes from drinking fewer sugary drinks, exercising more and losing weight.