Food sources high in refined sugars such as sweetened beverages, sodas and many juices can increase cancer risk. A 2010 study in the journal "Cancer Epidemiology, Biomarkers & Prevention" shows that individuals who consume two or more servings of soda per week have an 87 percent higher chance of developing pancreatic cancer compared to individuals who do not consume soft drinks. Other studies have shown links between sugar consumption and cancers of the stomach and colon. While sugar itself does not directly turn healthy cells into cancer, it is the preferred food source for cancerous cells and helps to promote tumor growth during the tumor formation process. Over time, a heavy sugar intake can also increase overall metabolic output of cells, increasing the amount of oxidative byproducts that are produced and released into their environment.
Fried foods increase one's risk of developing cancer, especially when they contain hydrogenated oils, trans-fats, and a byproduct of the deep-frying process called acrylamide. Acrylamide is a well- known tumor causing agent and also a potent neurotoxin, having adverse effects not only on the brain, but on the reproductive system as well. High carbohydrate foods such as potatoes readily produce acrylamide during the frying process. This places many fried potato products such as french fries, tater tots, potato chips and hash browns high on the list of cancer-causing foods.
Doughnuts are the culmination of three major classes of cancer causing foods; they are deep-fried, contain high levels of sugars and are based on heavily refined carbohydrates. The combination of by-products from the frying process together with heavy amounts of sugar and processed flour make doughnuts particularly risky to those hoping to reduce cancer risk.
Preserved, cured or pickled meats are a known risk factor in stomach cancer and other malignancies of the digestive system. Such meats are even more dangerous when ingredients such as sodium nitrate, a key preservative in hot dogs and other meat products is added into the mix. Hot dogs and other preserved, salted meats such as bacon or bologna should be consumed in moderation or avoided, especially for those at risk for stomach cancer.
When organic plant or animal matter is burned, a number of toxic, mutagenic by-products are formed. Many of these by-products are exactly the same as those produced in the burning of tobacco that accounts for the toxic and cancer promoting effects of cigarettes. According to the National Cancer Institute, cancers of the colon, stomach and other digestive system malignancies are associated with high intake of charred or burned meats. While this effect has not yet been rigorously established for other burned foods such as burnt toast, the same effect is possible.