Nutrition and Breast Cancer
There are three categories of breast cancer: genetic, familial, and sporadic. Despite getting a large amount of publicity, genetic breast cancer only makes up about 5-10% of all breast cancers. This is the type of breast cancer where a person has a mutation in a gene that predisposes to breast cancer. Once a genetic mutation is in the DNA code, there is a 50% chance that the mutation will be passed onto offspring.
Familial breast cancer occurs where people who live in the same environment, eat the same foods and have a similar lifestyle have a risk of getting the same diseases. This makes up about 40-60% of breast cancers, but may be an even larger percentage as we gain more information.
Sporadic breast cancers make up the rest. These are people who get breast cancer, seemingly with no specific reason. They are often the first in a family to be affected.
Breast cancer is a multifactorial disease. We are finding that a combination of lifestyle, diet, environmental factors, hormonal influence, and genetics often play roles in its development and course. We are led to believe that sporadic and familial breast cancers, when they develop, may be largely due to food and lifestyle choices. Here, we will focus on diet and nutrition.
When it comes to nutrition, it is best to eat a whole food diet, mostly plant based. The biggest piece of this is cutting out, as much as possible, all processed foods (ie: chips, soda, packaged meals, frozen dinners, bacon, lunch meats, hot dogs and other sausages, really anything with a label). Evolutionarily, our systems were only introduced to processed foods in the last century of the 200,000 years that humans have been in existence. It follows that our bodies know how to digest whole foods, but not so much factory made foods.
WHAT DOES THAT LEAVE?
All of the wonderful foods at the periphery of the grocery store are super for nutritional boosts–specifically, vegetables, fruits, legumes (beans, lentils, peas, etc), nuts, seeds, and grains (black, red or brown rice, quinoa, farro, kamut, amaranth, etc). There are increasing numbers of studies that also link eating meat (beef, but also pork, chicken, etc) to increased risk of cancer. There also seems to be a link between dairy intake (milk, cheeses) with increased breast cancer risk. If you cannot completely eliminate these foods, at least decrease them so that you are only eating them once or twice a week. Cutting out sugar also helps with risk reduction.
Although we do realize that diet plays a pivotal role in breast cancer occurrence, prevention, and recurrence, it is true that studies have not found the one specific food that is a “magic bullet” to keep us cancer free. However, we DO know that obesity and weight gain increase the risk of breast cancer.
In case vitamins are alluring to you, please understand that these are also heavily processed. There have been no studies showing a decreased risk of breast cancer with taking vitamins. Again, it is best to eat whole plant foods to get your vitamins and necessary minerals.
A big misconception is that soy increases the risk of breast cancer. While this may be true of heavily processed soy (such as soy isolates and total vegetable protein–TVP), if you are eating traditional, minimally processed foods such as tofu and soy milk (or, even better, edamame, a.k.a. soybeans), these foods seem to have a protective action against breast cancer.
Finally, there are certain supplements that have shown promise in breast cancer risk reduction. Turmeric (curumin) has been shown to be toxic to certain cancer cell lines (including breast cancer) in animal studies. More research needs to be done to evaluate the best dose for humans. Studies in Europe have shown promising information about decreasing breast cancer risk with increased ingestion of garlic and other vegetables in the allium family (onions, chives, leeks, etc). Certain mushrooms have been shown to have similar activity to medications that are used to treat breast cancer. Women whose Vitamin D levels are in the high normal range (45-85 ng/ml), appear to have a decreased risk of recurrence of breast cancer.
As you can see, there is a lot of exciting information being researched about diet and breast cancer. For now, the most important concept is that of eating minimally processed whole foods, which are mostly plant based.