More often than not we hear about foods to include in our diets to reduce breast cancer risk. I do think this is the best approach, but I am always up for looking at the other side of things. If you have breast cancer or are trying to prevent breast cancer, you may be wondering if there are any foods to eat less of. Research has uncovered some potential concerns with particular foods, and I have listed them below. The foods listed are in no particular order.
In research studies, trans-fats have been associated with an increased risk of breast cancer. Trans-fats are an unnatural form of fat, created through a process called hydrogenation. This process converts liquid vegetable oils into solid fats, which then become more like saturated fat – only worse. Some food manufacturers began using these fats because they were cost effective and improved the shelf life of their products.
Trans-fats are mostly likely to be found in fried foods, pastries, pie crusts, and store bought cookies (the kind that sit on the shelf). Shortening and margarine are sources of trans-fats. Check the ingredient list on your food products. If it says “hydrogenated oil” or “partially hydrogenated oil”, it contains trans-fats.
Though alcohol is not a food per se, it is important to be included in this discussion. Alcohol is one of the most well known dietary factors associated with breast cancer. Risk for breast cancer increases with a higher alcohol intake. At this time, researchers have not been able to pinpoint the reason why alcohol causes an increased risk. Some evidence points to a disruption in our hormone balance, while other evidence suggests that the products of alcohol metabolism are carcinogenic. All in all, it is smart to limit your intake all together.
Women who have had hormone positive breast cancer should not consume more than 3 alcoholic drinks per week. Women who are at increased risk (but have not had breast cancer) should limit intake to less than 5 drinks per week.
Heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs) are two chemicals that form on meat when it is cooked at high temperatures. These chemicals have been classified as “mutagens”, meaning they can cause damage to your DNA that could lead to cancer development.
Several studies have been done looking at how meat consumption affects breast cancer risk. One study found that women who consumed well-done meat had almost five times greater risk than women who consumed meat medium or medium rare. The researchers attributed the increased risk to the HCAs and PAHs present in well-done meat.
Slower cooking methods can reduce the formation of HCAs. These include steaming, braising, poaching, stewing, and microwaving. Grilling and pan-frying are two methods that encourage the formation of HCAs and PAHs.
*please note that I am not encouraging the consumption of raw or undercooked meat. Meat should be cooked to the level that meets food safety standards.
There is not a direct relationship between breast cancer and sugar, but consuming excess sugar can have an indirect effect for two reasons. One, food and drinks high in sugar cause the body to pump out more insulin. Insulin can act as a growth factor and promote the growth of cancer. Two, foods high in sugar are high in calories. Consuming too many calories causes gradual weight gain. Being overweight is a big risk factor for breast cancer.
6. Canned Foods
Canned foods contain bisphenol A (BPA). BPA is an industrial chemical used to make plastics and liners for food storage containers. The chemical leaches into the food from the can. Several studies have shown that BPA increases risk for breast cancer. BPA acts like a weak estrogen in the body and can alter the way our breast cells function.
It is almost nearly impossible to reduce your BPA exposure to zero. Worldwide, BPA is one of the most highly produced chemicals. Reducing your intake of canned food items will have a big impact on decreasing your exposure to this chemical.
There are a few companies that produce cans without BPA. One I know of for sure is Eden Foods.
7. Seafood High in Toxins like PCBs
Fish and seafood absorb pollutants from the waters where they live. PCBs or polychlorinated biphenyls are of particular concern. Research has indicated that PCBs can disrupt normal estrogen levels, which may cause an increase in breast cancer risk. Exposure to a low dose of PCB’s will not have a big impact on your health but if you routinely eat contaminated fish, it can become a problem.
Seafood low in toxins include: wild salmon from Alaska, freshwater coho salmon from the U.S, farmed rainbow trout, tilapia from the U.S, wild sardines from the Pacific, farmed oysters, farmed mussels, Alaskan cod, and farmed clams.
Please visit the following pages for the most update seafood safety information.
8. Processed Soy Foods
A large amount of research suggests that processed soy foods may be harmful to women who have breast cancer or women who are at risk. Studies have shown that when isolated soy compounds are consumed, they may be stimulatory to breast tumors. Processed soy foods include soy shakes, soy crisps, soy breads, soy bars, soy supplements, and fake meat products. If the label lists soy protein concentrate, soy isolate, or isolated soy protein, it should be avoided.
Moderate intake of whole soyfoods is considered safe. 1 to 2 servings of whole soyfoods are ok to include in your diet. Whole soyfoods include whole soybeans, edamame, roasted soybeans, soymilk, tempeh, tofu, and miso.
9. Milk from Cows Treated with Bovine Growth Hormone (rbGH or bST)
Bovine Growth Hormone is a type of hormone drug used to increase milk production in dairy cattle. It has been approved for use in the U.S since 1993. Studies have shown that dairy cows treated with rbGH have higher levels of IGF-1 (a type of growth factor) in their milk. There is a concern because women with breast cancer have shown to have higher levels of IGF-1 circulating in their system. Currently it has not been determined if the IGF-1 from milk treated with rbGH actually enters the human bloodstream. Until this is determined, I believe it is wise to avoid hormone treated milk. Plus, I don’t think it is compassionate to treat the dairy cows with this growth hormone, I have read that it can lead to pain and infection in the animals.