Studies have shown that following the ACS's cancer prevention guidelines for maintaining a healthy body weight, limiting alcohol intake (for those who drink), consuming a healthy diet, and being physically active is associated with a reduced risk of developing and dying from cancer.
The good news is that the rate of death from cancer in US has decreased by 25% over the past several decades. He said the study doesn't address how two or more risk factors, like smoking and drinking, might work together in some cancer cases and deaths.
Two types of cancer were found to have the most number of cases and deaths due to these risk factors - lung cancer and colon cancer.
A new American Cancer Society (ACS) study calculates the contribution of several modifiable risk factors to cancer occurrence, expanding and clarifying the role of known risk factors, from smoking to low consumption of fruits and vegetables.
"The results indicated that we can prevent a substantial proportion of cancers with the help of behavior and prevention strategies", said lead study author Dr. Farhad Islami, Strategic Director of Cancer Surveillance Research at the American Cancer Society. Also, a number of cancer types with likely, but as-yet unestablished associations with modifiable risk factors were not considered. "Nevertheless, these findings underscore the vast potential for reducing cancer morbidity and mortality through broad and equitable implementation of known preventive measures".
To perform a contemporary analysis of modifiable factors' contribution to cancer burden, the authors used published risk factor data from the International Agency for Research on Cancer and the World Cancer Research Fund/American Institute for Cancer Research.
These risk factors include cigarette smoking; secondhand smoke (SHS); excess body weight; alcohol intake; consumption of red and processed meat; low consumption of fruits and vegetables, dietary fiber, and dietary calcium; physical inactivity; ultraviolet (UV) radiation exposure; and infection with Helicobacter pylori, hepatitis B virus (HBV), hepatitis C virus (HCV), human herpes virus type 8 (HHV8), human immunodeficiency virus (HIV), or human papillomavirus (HPV). Excess body weight was associated with more than twice as many potentially preventable cancers in women as in men, whether represented by PAF (10.9% versus 4.8%) or actual case volume (85,680 versus 37,670).
With respect to cancer mortality, smoking accounted for nearly 30% (169,180) of all cancer deaths and more than half of cancer deaths attributable to potentially modifiable risk factors (265,150).
Next in line was excess body weight, with 7.8 percent of cases and 6.5 percent of deaths.
In 2014, the latest year with available incidence data, there were 1,596,486 new cases of cancer and 591,686 deaths from it.
Among all risk factors, cigarette smoking accounted for the highest proportion of cancer cases, the study found. Smoking accounted for more than 80% of lung cancer and 74% of all larynx cancers. Among women, the leaders in terms of number of cases of preventable cancers were breast (68,390), uterine (37,640), and colorectal (33,980).