Half of cancer deaths driven by bad habits, researchers find

*Eating processed meat, smoking, excess body weight, alcohol intake, physical inactivity implicated
*Sugar industry blocked research linking sucrose to heart disease, tumour from publication 50 years ago

At least half of United States (U.S.) cancer cases and deaths are caused by avoidable factors like smoking, eating processed meat and physical inactivity, a new American Cancer Society report reveals.

These graphs lay bare which lifestyle factors are the riskiest, and how much they affect your cancer risk, according to the study – with cigarette smoking easily the most dangerous activity.

They also reveal how some lifestyle habits are more risky for men than women, and vice versa.

Notably, cigarettes and processed or red meat and alcohol carry a much higher cancer risk for men than women, while women should be more wary of excess body weight than men.

Medical Director (MD), Dr. Farhad Islami, of the American Cancer Society, compiled a comprehensive list of known risk factors, and how risky each one is, based on previously-published data. His team then applied those figures to actual cancer data from 2014 to roughly calculate how many cases and deaths were attributable to those lifestyle factors.

The risk factors included in the analysis were: cigarette smoking; secondhand smoke; excess body weight; alcohol intake; consumption of red and processed meat; low consumption of fruits and vegetables; dietary fibre and dietary calcium; physical inactivity; ultraviolet light; and six cancer-associated infections, including herpes and Human Papilloma Virus (HPV).

Also, newly-uncovered documents have revealed that the sugar industry blocked the release of a study showing sucrose directly increases the risk of heart disease and cancer in 1968.

The research, which was funded and designed by the sugar industry, was intended to dispel fears that fructose-containing sugars affect blood lipids. But internal correspondence uncovered by researchers at the University of California at San Francisco, United States (U.S.), show that industry leaders pulled the plug on its publication after getting wind that it would prove the clearest link between sugar and disease ever found. The finding, published today in PLOS Biology, is the latest in a series of bombshell reports from investigative researcher Dr. Cristin Kearns and co-author Dr. Stanton Glantz, who was the first researcher to reveal Big Tobacco was hiding research on the danger of cigarettes in 1996.

Meanwhile, the American Cancer Society They found that an estimated 42 percent of all cancer cases in America (659,640 of the 1,570,975 cancers diagnosed in 2014) were attributable to these modifiable risk factors.

These factors were also the underlying cause of 45.1 percent of cancer deaths (265,150 of 587,521 deaths) that same year.

Staggeringly, they believe this is an understatement, since there are other risk factors that they couldn’t get the data for. There are also a number of cancers which are widely suspected to be caused by certain risk factors, but the links are not yet proven.

Based on the data Islami could compile, cigarette smoking accounted for the highest proportion of cancer cases and deaths: 19 percent of cases (298,970 people) and 28 percent of deaths (169,180 people).

Excess body weight was the second-riskiest, linked to 7.8 percent of cases and 6.5 percent of deaths, followed by alcohol intake (5.6 percent of cases and four percent of deaths), UV radiation (4.7 percent of cases and 1.5 percent of deaths) and physical inactivity (2.9 percent of cases and 2.2 percent of deaths).

Low fruit and vegetable intake accounted for 1.9 percent of cases and 2.7 percent of deaths, while HPV infection accounted for 1.8 percent of cases and 1.1 percent of deaths.

For women, excess body weight was far riskier than for men, since this risk factor is associated with 60 percent of uterine cancer, as well as 11 percent of breast cancers, which either exclusively or disproportionately affect women.

Physical inactivity is also riskier for women because it is more closely associated with uterine cancer than any other cancer types. By Dr Islami’s estimates, lack of exercise drives 26.7 percent of uterine cancers, as well as 16.3 percent of colorectal cancers, and 3.9 percent of female breast cancers.

Smoking, meanwhile, was a higher risk factor for men, causing a third of male cancers, compared to one-fourth of female cancers.

Alcohol intake was associated with almost half of oral cancers in men (46.3 percent) and more than one-fourth (27.4 percent) in women. It also drives 24.8 percent of liver cancers in men, compared to 11.9 percent in women, and 17.1 percent of colorectal cancers in men, compared to 8.1 percent in women.

UV radiation was associated with 96 percent of melanomas of the skin in men and 93.7 percent in women.
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