1. High intake of processed foods

Many different substances are added to commercially prepared foods, such as artificial colors, chemical flavors, salt, sugar or artificial sweeteners (read my article about the top 10 worst ingredients in food).

These additives are constantly investigated by researchers to check if any of them is thought to be of a real risk. Sometimes a particular additive or some additives are thought to be of a cancer risk. Heavily salted, smoked and pickled foods, for example, may increase the risk of stomach cancer.

2. High intakes of red meat, processed meat or charred food

It has been found that bowel and stomach cancer are more common in people who eat lots of red and processed meat.

Red meat includes all fresh, minced and frozen beef, pork, lamb or veal. Also processed meats posses a risk for cancer. These have been preserved in some way other than freezing and include bacon, ham, salami, sausages, corned beef, black pudding, pâté and tinned meat.

3. Sugar

Research shows that being overweight or obese increases your risk of cancer. This is because obesity may cause changes in hormone levels or insulin that might increase the risk of developing breast, colon or uterine cancer. Therefore limiting the amount of sugar in your diet is important. Diets high in sugar and refined carbohydrates can lead to overweight and obesity, which indirectly increases cancer risk over time.

4.  Fried food, French fries, potato chips and snack food

French fries, potato chips and other snacks may contain high levels of acrylamide, another carcinogenic substance that forms when foods are heated at high temperatures, such as during baking or frying. Acrylamide may be found in any food heated to a temperature above 250° F, but potato chips and French fries have been found to contain the highest levels among foods tested.

Cooking methods such as frying, baking or roasting are more likely to produce acrylamide, while boiling, steaming, and microwaving appear less likely to do so. Longer cooking times and cooking at higher temperatures can increase the amount of acrylamide in foods further.

5. Excess alcohol

There is a strong scientific consensus of the link between alcohol drinking and several types of cancer. The more alcohol a person drinks regularly over time—the higher his or her risk of developing an alcohol-associated cancer. According to Cancer Research UK and American Cancer society, alcohol can increase the risk of a number of cancers, such as mouth cancer, liver cancer, breast cancer, bowel cancer and throat cancer.

(Source: http://www.healthyandnaturalworld.com)