Cancer: 42% of cases down to risk factors you can change

A large new study from the American Cancer Society inventories the risk factors for various types of cancer.
Those findings shed much-needed light on the proportion of cancers that could be prevented by making the necessary lifestyle changes.
Smoking is the top risk factor for all cancer cases, according to new research.

The new research examined a total of 1,570,975 cancer cases, 587,521 of which resulted in death.



These 9 modifiable risk factors are active measures people can undertake to reduce their risk of cancer.

In the new study, such factors included:

  • alcohol intake
  • smoking (both first- and second-hand)
  • excess body weight
  • a low content of fiber in one’s diet
  • the consumption of processed red meat
  • a low intake of fruit and vegetables
  • ultraviolet (UV) radiation
  • low calcium
  • a lack of physical activity

The top 3 risk factors were smoking, excessive weight, and alcohol use.

The study revealed that 42% of all cancers and over 45% of all cancer deaths were down to modifiable risk factors.
    • 19% of all cancer cases and almost 29% of related deaths were attributable to cigarette smoking.
    • 7.8% of cancers and 6.5% of cancer deaths were attributed to excess body weight
    • 5.6% of cases and 4% of deaths were down to alcohol intake.
    • 4.7% of cancer cases and 1.5% of deaths were due to UV radiation
    • 2.9% of cancer cases and 2.2% of deaths were accounted for from lack of physical activity


Certain major cancers had a high portion of cases attributable to modifiable risk factors. Lung cancer was at the top, with 85.8 percent of cases down to such factors, 81.7 percent of which were attributable to smoking alone.

Over 70% of liver cancer cases, almost 55% of colorectal cancer cases, and nearly 29% of breast cancer cases could be attributed to modifiable risk factors.
Additional findings include the fact that UV radiation was linked to 96% of skin melanoma cases, and excess body weight to over 60% of uterine cancers.
50% of esophageal cancers were tied to smoking. Cigarettes were also associated with nearly 47% of bladder cancer cases. Finally, over 10% of colorectal cancers were associated with a low intake of dietary fiber.


‘Knowing about preventive measures’ is key

The study authors remind the public of the four key factors that everyone can keep in check: body weight, alcohol consumption, diet, and physical activity.
The combined influence of these 4 factors made up nearly 14% of cancer risk in women and over 22% in men.
The authors concluded “Increasing access to preventive healthcare and awareness about preventive measures should be part of any comprehensive strategy for broad and equitable implementation of known interventions to accelerate progress against cancer.”