We live in an age of conscientious eating.
Nutrition labels are checked.
Portion sizes are kept small.
Green smoothies and avocado toast have now become a staple of our weekend brunches.
These are all great habits to have and will likely play more than a small role in reducing our cancer and heart disease risk.
But just as important as tracking and including nutrient rich foods in our weekly dietary line-up is the avoidance of certain foods and beverage items.
The American Cancer Society in their latest 2020 guidelines for diet and physical activity for cancer prevention revealed 5 food items that should be avoided to reduce cancer risk. Here they are:
Processed Meats and Red Meat
In 2015 the World Health Organization (WHO) and the International Agency for Research on Cancer (IARC) classified processed meats as a carcinogen (Group 1) and red meat as a probable carcinogen (Group 2A). To add fuel to the fire (pun intended), they added another word of caution regarding preparation of these food items: grilling, frying or smoking red and processed meats (as well as poultry and fish albeit to a lesser extent) at high temperatures can cause a chemical reaction within the meat forming carcinogenic heterocyclic amines (HCAs). Naturally, the researchers found that the higher contents of the HCAs correlated to the “done-ness” of the meats. Thus, the more well done the meat, the higher the HCA content.
Other possible culprits that increase cancer risk within these products, particularly in processed meats, include nitrate and nitrite preservatives that transform into cancer causing chemicals when we ingest them called N-nitroso compounds (NOCs). Another compound, called heme iron, which is intrinsically within red and processed meats further stimulate the production of NOCs within our bodies.
Colorectal cancer appears to have the greatest association with ingestion of red and processed meats. Pancreatic and prostate cancer have also demonstrated significant associations as well. There also appears to be a dose dependent association with meat intake and cancer risk. A meta-analysis of 10 studies revealed that for every 50 grams of daily processed meat intake, the risk of colorectal cancer increases by 18%.
Added Sugar
Although added sugars are not directly linked to cancer in and of itself, excess consumption of it can lead to many high-risk conditions that are indeed associated with malignancies. These conditions that include obesity and diabetes are associated with 13 types of cancer (See infographic from the CDC below).
Added sugars come in a variety of forms such as white sugar, brown sugar, raw sugar, corn sweeteners, agave nectar, and high-fructose corn syrup to name a few. Added sugars are also commonly found in fast food items and heavily and ultra-processed food items (think frozen pizza, fat-free products, breads, cereal, frozen pizza and sodas).
So, what can we do to lower our risk? Decrease intake of added sugars, of course! The Dietary Guidelines for Americans 2020-2025 recommend that all Americans 2 years and older limit added sugars to 10% of total calories. This means, for a standard 2000 kcal diet, 200 kcal or 50 grams of sugar is the max suggested amount.
Acrylamide
Acrylamide has been classified as a probable carcinogen (Group 2) by the IARC. It is formed as a byproduct of the Maillard reaction which occurs when carbohydrate rich food items are overheated (think browning process of toast). Specifically, it develops when asparagine reacts with certain sugars when heated to high temperatures. Food items that have the highest contents include: French fries, potato chips, cookies, breakfast cereals, prune juice and instant coffee.
Now, most of the dangers of acrylamide have been demonstrated in animal studies and not strongly evidenced in epidemiologic human studies. Our suggestion is to be mindful of Acrylamide’s low-level possible human cancer link.
The FDA has suggested ways to decrease acrylamide in our food items. These include: decreasing intake of fried plant based foods, toasting bread to a light brown color instead of a dark brown color, and keeping potatoes out of the fridge for storage as this can increase acrylamide formation during cooking.
Alcohol
Alcohol is classified as a Group 1 carcinogen by the IARC. The American Cancer Society recommends that it is best to NOT drink any alcohol. Alcohol use is attributed to 6% of all cancers and 4% of all cancer related deaths in the U.S.. However, for individuals who do drink, they should limit intake to 1 alcoholic drink per day for women and 2 drinks for men.
A common misconception is that there are “safer” alcoholic beverages compared to others such as red wine. However, when it comes to cancer risk, this has proven to not be the case. Ethanol is the common denominator of all alcoholic beverages and is the culprit for the associated cancer risk.
Arsenic Contaminated Food Items
Popularized as the cause of death of many characters in Agatha Christie novels, Arsenic is a heavy metal that is widely found in nature, particularly in soil and water. Its inorganic form is very toxic. Perhaps the biggest source of arsenic worldwide that poses a public health threat is contaminated groundwater. The United States is unfortunately one of the countries that have higher levels of inorganic arsenic present in its groundwater in addition to Bangladesh, Chile, China, India, Mexico and Argentina.
Drinking water and crops that are irrigated with contaminated water along with food prepared with contaminated water are the sources of exposure. Food sources that have been linked to higher levels of inorganic arsenic are rice and rice-based cereals as well as apple juice. The FDA has a recommended limit of 100 micrograms/kg or 10 micrograms/Liter.
The IARC classifies inorganic arsenic as carcinogenic to humans (Group 1). Cancers that have been linked to arsenic include skin, bladder and lung cancers.
What can we do to limit our exposure to inorganic arsenic? Regarding drinking water, check with your county’s water department to get access to their annual water quality report or enter your zip code in the Environmental Working Group’s Water database to check contaminant levels in your local drinking water. Reverse osmosis water filters and the Zero Water pitcher filter have been shown to significantly lower inorganic arsenic levels. Limit intake of rice products and fruit juices that are known to have higher inorganic arsenic levels. Regarding rice in particular, the FDA suggests that cooking rice in larger amounts of water (like how pasta is cooked) and then draining that water can decrease the inorganic arsenic content by approximately 40-60%!
