Can eating certain foods cause the development of various types of cancer?
There has been a great deal of attention paid to this over the course of many decades. The evidence indicates that there is an association between the intake of certain foods like dairy products, fruits, and vegetables and the development of cancer. The regular intake of these foods is associated with a lowered risk of developing certain types of cancer. However, are there foods that cause an increase in the incidence of cancer? Some newly published research can shed some light upon this important subject.
The study looked at cancer incidence data from 157 countries which evaluated the incidence of 21 different types of cancer from 87 studies and compared the incidence rates to various risk factors for cancer development. This data was gathered in 2008.
What this study found is that people who consumed the most animal products in their diet had the highest rate of cancers of the breast, kidney, pancreas, prostate, and thyroid. The consumption of alcohol was only found to be associated with the development of colorectal cancer. The addition of artificial sweeteners in the diet was associated with an increased incidence of cancer of the brain, pancreas, and prostate.
“My study reiterates that animal products are an important risk factor for many types of cancer,” said the study author. “The data also show that there is a 15- to 30-year lag between diet and cancer incidence. Eating animal products is as important as smoking for increasing the incidence of all cancer types (apart from lung cancer).”
This study found that the consumption of animal fat is associated with an increased risk of developing lung cancer. The study author attributes this fact with the increased incidence of lung cancer in countries like Japan, despite lowered rates of smoking. This is happening because the Japanese diet has shifted to a westernized diet—much higher in animal fat. The incidence of cancers including those occurring in the breast, colon, and prostate has increased in westernized countries following a 20-year lag.
This pattern of cancer development in westernized countries is attributed to the corresponding changes in diet involving the increased consumption of animal products with reduced intakes of fish, fruits, and vegetables. Animal products contain high amounts of the fatty acid known as arachidonic acid. Arachidonic acid converts to chemicals which can greatly encourage the development of inflammation. Chronic inflammation can cause tissue damage from toxic free radicals and may set the stage for pre-cancerous cell development.
Certainly after 10-20 years, chronic inflammation could be an important cause of cancer, especially if the intake of the “good” anti-inflammatory fats from the omega-3 family found in fish and plants are not being consumed in adequate amounts. Animal products can be an important addition to your diet, but moderation is key. Organic, free range meat contain much less arachidonic acid, no growth hormones, and are much leaner and safer to consume.
Sources:
Nelson, R., “Diets Heavy in Meat Boost Risk for Certain Cancers,” Medscape web site; http://www.medscape.com/viewarticle/819017?nlid=45183_1885&src=wnl_edit_dail&uac=205413HV, last accessed Jan. 21, 2014.
Grant, W., “A Multicountry Ecological Study of Cancer Incidence Rates in 2008 with Respect to Various Risk-Modifying Factors,” Nutrients 2014; 6(1): 163-189.