By SUSAN CALLAHAN, Associate Editor and Featured Columnist
This year, almost 300,000 women will be diagnosed with breast cancer. Of this total, 231,840 women will be diagnosed with invasive breast and another 62,290 will be diagnosed with carcinoma in situ, a non-invasive early stage breast cancer, according to the American Cancer Society's 2015 estimates.
Once you have been diagnosed with breast cancer, the real work of bolstering your health and your chance for long term survival begins.
Fortunately, there are foods that can greatly help.
One of the most promising nutrients in terms of boosting survival are omega 3 fatty acids. Omega 3 fatty acids, specifically, eicosapentaenoic acid (EPA) and docosahexaenoic acid ( DHA), have long been studied by scientists from all over the world for their potential in preventing the start of cancerous tumors ---a process known as “tumorigenesis”.
Less studied is whether omega 3 fatty acids actually help to lower the risk of death in women who already have been diagnosed with breast cancer.
How much do omega-3 fatty acids help in lowering your risk for recurrence of breast cancer? Does it make a difference if you get your omega-3 fatty acids from foods as opposed to fish oil supplements?
Omega-3 Fatty Acids Lower Your Chances of Getting Breast Cancer
Several studies have established that women who eat a high intake of fish have a lower risk for getting breast cancer in the first place. A 2003 study from Keck School of Medicine of the University of Southern California examined the health records of 35,298 women from Singapore of Chinese descent and found that women with high fish intake have a 26% lower risk for developing breast cancer.
How high is “high fish intake”? How much fish are we talking about? Well, the lowest quartile of women ate 25 grams or less of fish every day. The highest quartile are 47 grams of fish per day. Breast cancer risk seems to drop off a cliff as your fish intake climbs above 26 to 35 to 47 grams a day. As a comparison, a 4 ounce serving of fish is 35 grams.
Fish with Omega 3 Help to Improve Chances of Survival After Breast Cancer Diagnosis
In 2011, a landmark study was undertaken to address just this issue. The study, led by Dr. Ruth E. Patterson of University of California, San Diego and Dr. Shirley W. Flatt of the University of Arizona of , studied 3081 women who had been diagnosed with early stage breast cancer.
Over an 11-year period, from 1995 to 2006, the scientists took careful inventory of how much fish with omega 3 fatty acids the women consumed daily. They separately tracked the amount of omega-3 fatty acids the women consumed from fish oil supplements.
At the end of the 11 years, they recorded the number of survivors, the number of women who had recurrences of the first breast cancer or a new invasive breast cancer, deaths from breast cancer and the number of deaths from other causes.
What they found was that there is a strong association between the amount of omega-3 fatty acids you consume from food and your chances of survival. Women who consumed an average of 73 mg of DHA and EPA per day had a 25% lower risk of recurrence of breast cancer. Women who consumed an average of 365 mg per day of DHA and EPA from food had a 40% lower risk of recurrence of breast cancer or death from any other cause.
Getting 365 mg of DHA and EPA is not hard if you eat the right fish. Salmon, in general, is rich in DHA and EPA though the particular species of salmon will vary in the amount of omega-3 fatty acids they have.
You will also find widely varying reports of how much DHA and EPA is contained in a given species. We choose to rely on the percentages given by the US Department of Agriculture (USDA).
According to the USDA, a serving of Atlantic wild cooked salmon has 1429 mg of DHA and 411 mg of EPA. Pacific and jack mackerel, cooked, has 1195 mg of DHA and EPA. Atlantic herring, cooked has 1105 DHA and 909 EPA.
Sardine's DHA and EPA content also vary widely. The USDA sources do not list this information. However, according to the National Heart Foundation of Australia, a can of sardines packed in tomato sauce has 2625 mg total DHA and EPA while sardines packed in oil have 1700 mg DHA and EPA.
From any of these tasty fish, you should easily be able to get more than the 365 mg per day threshold which was associated with the 40% lower risk of breast cancer recurrence and death.
But bear in mind that these remarkably good results were only found in cases where the DHA and EPA were consumed from fish as food. What about fish oil supplements? Do they also lower your risk of breast cancer recurrence?
Fish Works But as for Fish Oil Supplements...Not So Much
In contrast to actual fish food, fish oil supplements have not been as well studied in terms of their ability to inhibit the recurrence of breast cancer. Some studies have made the observation that, as fish oil supplements have become popular in the United States, that a parallel drop in breast cancer deaths has occurred.
Perhaps the most important study on fish oil supplements and breast cancer was completed in 2010 led by Dr. Theodore Barsky of The Fred Hutchinson Cancer Research Center at the University of Washington. That study examined a the answers to a questionnaire completed by 35,016 postmenopausal women between the ages of 50 and 76 to determine the link, if any, between supplements they took and their risk for breast cancer.
For ductal but not lobular cancers, those who took fish oil supplements had a 32% lower risk of developing breast cancer.
Since this study’s publication, numerous health authorities have taken pains to point out fish oil’s effectiveness has yet to be proven as a breast cancer deterrent. We will need to see many more studies, in which the intake of fish oil is determined not just from questionnaires but under more controlled, verified conditions.
For now, the jury is still out on fish oil supplement’s effectiveness in lowering breast cancer risk.
Curcumin Induces Breast Cancer Cells to Commit Natural Suicide
Curcumin (diferuloylmethane) is the compound which gives tumeric and curry a yellow color. Many studies have found that curcumin has properties which inhibit the formation of various types of cancers.
Curcumin induces breast cancer cells to enter “apoptosis”, a natural cell death, according to a 2002 study from led by the Animal Physiology Section, Bose Institute in India and Cleveland Clinic Foundation’s Department of Molecular Biology.
Curcumin also protects normal cells from developing genetic defects after they have been exposed to radiation. Curcumin has been found to reduce the number of cells with chromosomal aberrations and to protect normal cells from chromatid breaks due to exposure to γ-radiation, a 1998 study led by Dr. K.C. Thresiama of the Amala Cancer Research Centre, in India.
This important result was duplicated in laboratories around the world, including by a 2013 team from the Health Radiation Research Department, National Centre for Radiation Research and Technology, Atomic Energy Authority in Egypt.
What these studies suggest is that after a diagnosis of cancer, and after consultation with your doctor, adding curcumin to your diet could help to protect your healthy breast cells from becoming defective after exposure to radiation. More human studies are needed in this area but curcumin’s efficacy certainly is promising.