Cancer is the No. 2 cause of death in the US, second only to heart disease.
It fundamentally affects the way our cells grow and divide, changing them in perverse ways. All cancer is a result of damage or genetic mutations in our DNA. The nasty, debilitating class of diseases spreads through a body like an invading army, as toxic cells grow relentlessly into unruly tumors.
Some cases of cancer are out of our control, determined by genetic defects and predispositions passed down from one generation to the next, or spurred by genetic changes we undergo through our lifetime.
But we also know that breathing in certain substances, eating specific things, and even using some kinds of plastics ups the risk of developing some deadly cancers.
Here are some known carcinogens (cancer-causers), as well as a few more things scientists are zeroing in on as prime suspects.
SEE ALSO: A study of more than 100,000 people has found that one food group is closely linked with cancer
Sugar
Scientists now know that eating too much sweet stuff can not only lead to diabetes, but actively damage your cells and increase your risk of developing cancer.
But that's not all.
New research suggests that sugar may fuel tumor growth in the body — because cancer loves to use sugar as fuel.
"The hyperactive sugar consumption of cancerous cells leads to a vicious cycle of continued stimulation of cancer development and growth" Johan Thevelein, a Belgian molecular biologist, said in October after the release of his study.
Scientists say that the groundbreaking research gives us a better understanding of how sugar and cancer interact and that it could one day help create targeted diet strategies for patients.
Processed foods
Any food that comes in a crinkly plastic wrapper, is industrially sealed, and is designed to last for months without spoiling may be a quick on-the-go fix for a hunger pang, but it's also most likely increasing your risk of cancer.
Scientists in France recently zeroed in on a link between people who eat more processed foods and those who develop cancer.
They're not sure yet whether the problem is the shelf-stabilizing ingredients, the plastic packaging, or some combination of the two. And because their study was correlative, it's possible there's some other hidden factor at work.
Smoking
Though the tobacco industry tried to cover this one up, we've known for years that tobacco smoke has at least 70 cancer-causing chemicals inside.
And it's not just smokers who are affected — people who inhale secondhand smoke can develop deadly forms of cancer too.
The Centers for Disease Control and Prevention says: "Nonsmokers who are exposed to secondhand smoke at home or at work increase their risk of developing lung cancer by 20-30%."
People who chew their tobacco are at increased risk too.
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