Cancer is a systemic disease with various causes, some of which include a poor diet, toxin exposure, nutrient deficiencies and to some extent genetics. One extremely important way to prevent and/or treat cancer is nutritionally, through eating a nutrient-dense diet and avoiding things that are known to increase cancer risk.
But for many people navigating the modern-day food system often seems overwhelming. Ingredients in ultra-processed foods are being blamed for everything health-related, from cancer and diabetes, to reduced kidney function and bone loss. Only adding to the confusion, sometimes even the way we cook otherwise-healthy foods puts them in the cancer-causing foods category.
Unfortunately, until food manufacturers are forced to clean up the ingredients they use in their products, it’s up to us to avoid the worst kinds. Here, I’m outlining the association between certain cooking techniques, unhealthy ingredients found in processed foods, and the risk for developing cancer. Researchers have known about the dangers associated with some unhealthy habits and cancer-causing foods for decades, while others are just now emerging as possible culprits.
Certainly when it comes to cancer prevention, more research is still needed. But for now, I’ll share the types of foods and ingredients I’d recommend avoiding most, plus tips for how to transition to eating an anti-cancer diet.
What Are Cancer-Causing Foods?
What makes some foods carcinogens (in other words cancer-causing)? Foods that potentially contribute to cancer can include any number of chemicals, pesticides, preservatives and additives. For example, these are some of the factors that cause certain foods to be very unhealthy— not only potentially increasing your risk for cancer, but also causing problems like allergies, leaky gut, obesity and inflammation:
- Pesticides and Herbicides: Industrial farming practices have loaded our produce, air, water, soil and animals at the bottom of the food chain with noxious chemicals. The best way to avoid consuming pesticides is to buy organic and ideally locally-grown foods.
- Animal Products with Hormones and Antibiotics: Conventional meat and dairy products are often produced using antibiotics and hormones which help increase production, but can also cause effects such as estrogen disruption once consumed. Don’t be fooled by “natural” or “free-range” labels, which don’t always say much about how food is produced. Buy pasture-fed, locally raised animal products that are labeled as hormone and antibiotic-free.
- Added Sugar & Artificial Sweeteners: Recently studies have linked higher sugar diets to increased risk for certain types of cancer. Artificial sweeteners such as aspartame, saccharine and sucralose may generate damaging free radicals in the body. High fructose corn syrup, although manufacturers refer to it as a “natural” sweetener, is highly processed, artificial and capable of contributing to obesity and yeast growth, among other negative health effects.
- Food Additives: Nitrates, sulfites, food dyes and coloring and MSG have all been linked to free radical damage in the body. The best way to avoid these is to stay away from products that contain unknown and unpronounceable ingredients.
- Pasteurization: It’s not just milk that is pasteurized (heated to very high heats) in order to kill bacteria. Yogurts, fruit juices, and many of the foods in our grocery stores have been treated with a high heat process that destroys nutrients and generates free radicals in the body. Pasteurization is used as a substitute for proper sanitation and to unnaturally prolong the shelf life of foods.There isn’t much evidence directly linking pasteurization to cancer, but pasteurized foods can still be problematic when it comes to increasing inflammation and gut-related problems.
Here are examples of some cancer-causing foods you might not realize are in your diet:
1. Processed Meats
While quality meats, fish and dairy products can be included in an anti-cancer diet, processed meats are definitely something to avoid. The American Cancer Society states on their website that “The International Agency for Research on Cancer (IARC) has classified processed meat as a carcinogen, something that causes cancer. And it has classified red meat as a probable carcinogen, or something that probably causes cancer.” (1)
A recent meta-analysis of 800 studies found evidence that eating 50 grams of processed meat every day (equal to about 4 strips of bacon or one hot dog) increased the risk of colorectal cancer by 18 percent.
Processed meats are those that have been treated, altered or preserved to improve taste and prolong freshness. They can contain additives such as nitrates and tend to be very high in sodium. A clue that is a meat is processed is if it’s been prepared in any of the following ways: salting, curing, smoking. Examples of processed meats include hot dogs, ham, bacon, sausage, and some deli meats/cold-cuts. (2)
2. Fried, Burnt and Overly-Cooked Foods
In early 2017, Britain’s Food Standards Agency launched a campaign to help people better understand, and to avoid, the toxin called acrylamide. Acrylamide is found in things like cigarette smoke and is also used in industrial processes like making dyes and plastics. What’s surprising is that acrylamide is also a chemical that forms on certain foods, especially starchy foods like bread, crackers, cakes and potatoes, when they are cooked for long periods at high temperatures. (3)
The International Agency for Research on Cancer classifies acrylamide as a “probable human carcinogen” based on data showing it can increase the risk of some types of cancer in lab animals. (4) Acrylamide is mainly found in highly-cooked plant foods like potato and grain products, such as French fries, potato chips, and to some extent coffee.
The chemical reaction occurs when certain starchy foods are cooked above about 250° F. This causes sugars and the amino acid asparagine to create acrylamide. Note: Acrylamide does not form (or forms at lower levels) in dairy, meat, and fish products.
3. Added Sugar
Sugar can do more than increase your calorie intake and contribute to an expanding waistline— high consumption of added sugar has also been associated with increased cancer risk. There’s evidence that added sugars, such as high fructose corn syrup, may increase the risk of esophageal cancer, small intestine cancer, colon cancer and breast cancer. (5, 6, 7)
A number fo studies have found that sugar not only contributes to problems like obesity and diabetes, but is also linked to increased growth of tumors and metastasis.
Here’s another reason to avoid too much sugar: Studies have found that people getting 17 to 21 percent of calories from added sugar face a 38 percent higher risk of dying from cardiovascular disease compared to those who got just 8 percent of their calories from sugar. (8)
4. Foods High In Additives
A 2016 study published in Cancer Research discovered a link between common food additives and colon cancer. Researchers at Georgia State University’s Institute for Biomedical Sciences found that mice that regularly ingested the dietary emulsifiers called polysorbate-80 and carboxymethylcellulose experienced exacerbated tumor development and increased, low-grade inflammation and colon carcinogenesis. (9)
These emulsifiers act as “detergent-like” ingredients in the gut, significantly changing the species composition of the gut microbiome. Alterations in bacterial species can result in bacteria expressing more flagellins and lipopolysaccharides; in other words, changes in the microbiome can interfere with functions of the immune system, promote inflammation and increase harmful gene expressions.
What types of processed foods and products contain these emulsifiers? Examples include dairy products such as ice cream, creamy beauty products, toothpaste, mouthwash, laxatives, diet pills, water-based paints, detergents and even vaccines.
5. Rice Products
Drinking water contaminated with arsenic can increase a person’s risk of lung, skin and bladder cancers. That’s why there are clear limits set for the amount of arsenic allowed in water. But what about the arsenic present in the food supply? Turns out, most Americans get more arsenic from the foods in their diet than from the water they drink. So is arsenic poisoning from foods like rice something you need to consider?
While babies potentially face the highest risk, excess arsenic isn’t good for any of us. A 2012 Consumer Reports investigation found arsenic in every brand of infant rice cereals it tested – nearly ten times the legal limit for drinking water! Subsequent testing was even more dire: just one serving of infant rice cereal can put children over the weekly maximum advised by Consumer Reports. (10)
According to the The Environmental Working Group’s (EWG) website, “Heavy metals like arsenic, cadmium and lead are naturally present in water and soil. In some places, intense concentrations exist as a result of industrial pollution and decades of agricultural use of lead- and arsenic-based pesticides.” (11)
Organizations like the EWG and the World Health Organization now recommend limiting consumption of rice and rice-based foods (including those containing rice flour) when possible and instead eat a varied diet of healthy lower-arsenic grains and sweeteners.
- Cancer-causing foods include those that contain pesticides, additives, added sugar or artificial sweeteners, processed meats, burnt foods, fried foods and other chemicals.
- Examples of cancer-causing foods and ingredients are: french fries, hot dogs, deli meats, sausage, ice cream, refined rice and other gains, high fructose corn syrup, processed vegetable oils, and trans-fats.
- To follow an anti-cancer diet lower your toxin intake, support the body’s cleansing and detoxifying processes, and eat unprocessed nutrient-rich foods.