High-fat dairy products linked to poorer breast cancer survival

March 14, 2013, Kaiser Permanente

Patients who consume high-fat dairy products following breast cancer diagnosis increase their chances of dying from the disease years later, according to a study by Kaiser Permanente researchers.

The study, published in the Journal of the National Cancer Institute, is the first to examine the relationship between high-fat and low-fat following a diagnosis of and long-term breast cancer survival.

Previous studies have shown that higher to estrogen is a causal pathway to breast cancer. are believed to be elevated in consumed in the Western world, because most of its milk comes from pregnant cows. Estrogenic hormones reside primarily in fat, so levels are higher in high-fat than in low-fat dairy products.

The researchers studied a cohort of women who were diagnosed with early-stage, between 1997 and 2000, primarily from Kaiser Permanente's Northern California region (83 percent) and the Utah Cancer Registry (12 percent).

Those consuming larger amounts of high-fat dairy (one serving or more per day) had "higher as well as higher all-cause mortality and higher non-breast cancer mortality," wrote lead author Candyce H. Kroenke, ScD, MPH, staff scientist with the Kaiser Permanente Division of Research, and co-authors.

"Specifically, women consuming one or more servings per day of high-fat dairy had a 64 percent higher risk of dying from any cause and a 49 percent increased risk of dying from their breast cancer during the follow-up period," said Kroenke. The category of high-fat dairy products researchers tracked included cream, whole milk, condensed or evaporated milk, pudding, ice cream, custard, flan, and also cheeses and yogurts that were not low-fat or non-fat.

In general, the women studied reported that they consumed low-fat milk and butter most often, and they consumed relatively limited amounts of low-fat dairy desserts, low-fat cheese and high-fat yogurt. Overall, low-fat dairy intake was greater (median 0.8 servings per day) than high-fat dairy (median 0.5 servings per day).

The study found an association between high-fat dairy and breast cancer mortality, but no association with low-fat dairy products and breast cancer outcomes.

"High-fat dairy is generally not recommended as part of a healthy diet," said senior author Bette J. Caan, DrPH, research scientist with the Kaiser Permanente Division of Research. "Switching to low-fat dairy is an easy thing to modify."

Women entered into the cohort approximately two years after their breast cancer diagnosis. At the beginning of the study, 1,893 women completed a self-administered food-frequency questionnaire, and 1,513 of these women completed a follow-up questionnaire six years later. They were followed for 12 years on average following study entry.

The women were asked how often they consumed dairy foods during the previous year; what portion sizes they generally consumed; which products they ate, including milk, cheese, dairy desserts, yogurt, and beverages made with milk (such as hot chocolate or lattes); and whether the dairy products were full fat, low fat or nonfat.

Of the total sample, 349 women had a recurrence of breast cancer and 372 died of any cause, 189 (50.8 percent) of them from breast cancer.

This research was part of the Life After Cancer Epidemiology (LACE) study, one of several efforts by investigators with the Kaiser Permanente Division of Research to consider the role of lifestyle factors such as nutrition, exercise and social support on long-term breast cancer survival and recurrence. While hundreds of studies have examined the role of lifestyle factors in cancer risk and prevention, this study is one of a small but growing number that focus on the role of lifestyle factors after a breast cancer diagnosis.

For example, the Pathways study of breast cancer survivorship, based at the Division of Research, is collecting and analyzing data about women's genetic background, tumor characteristics and lifestyle choices immediately after diagnosis. Findings from this study, along with the LACE study, are providing objective information to help guide women as they make decisions following a breast cancer diagnosis; among these findings are that soy decreases the risk of breast cancer recurrence, quality of life after diagnosis influences outcomes, and physical activity is beneficial.

Susan E. Kutner, MD, chair of the Kaiser Permanente Northern California Regional Breast Care Task Force, said that the new study bolsters the counseling that Kaiser Permanente gives breast cancer survivors about the importance of a low-fat diet, as well as exercise and weight management, in preventing recurrence of the disease. "Women have been clamoring for this type of information," Kutner said. "They're asking us, 'Tell me what I should eat?' With this information, we can be more specific about recommending low-fat dairy products."

Explore further: Eating low-fat dairy foods may reduce your risk of stroke

Related Stories

Eating low-fat dairy foods may reduce your risk of stroke

April 19, 2012
If you eat low-fat dairy foods, you may be reducing your risk of stroke.

The role of fat in assessing breast cancer risk

October 26, 2011
It is known that a high proportion of dense breast tissue, as seen with a mammogram, is associated with a high risk of breast cancer. But the role of non-dense fat tissue in the breast is less clear. New research published ...

High-quality personal relationships improve survival in women with breast cancer

November 9, 2012
The quality of a woman's social networks—the personal relationships that surround an individual—appears to be just as important as the size of her networks in predicting breast cancer survival, Kaiser Permanente scientists ...

Breast density does not influence breast cancer death among breast cancer patients

August 20, 2012
The risk of dying from breast cancer was not related to high mammographic breast density in breast cancer patients, according to a study published August 20 in the Journal of the National Cancer Institute.

Study finds least aggressive form of breast cancer still poses risk for death years later

September 18, 2012
Women with the most common and least aggressive subtype of breast cancer were still at risk of death from the disease more than 10 years after diagnosis, according to a Kaiser Permanente study published in the journal Cancer ...

Recommended for you

Researchers develop a remote-controlled cancer immunotherapy system

January 15, 2018
A team of researchers has developed an ultrasound-based system that can non-invasively and remotely control genetic processes in live immune T cells so that they recognize and kill cancer cells.

Pancreatic tumors may require a one-two-three punch

January 15, 2018
One of the many difficult things about pancreatic cancer is that tumors are resistant to most treatments because of their unique density and cell composition. However, in a new Wilmot Cancer Institute study, scientists discovered ...

New immunotherapy approach boosts body's ability to destroy cancer cells

January 12, 2018
Few cancer treatments are generating more excitement these days than immunotherapy—drugs based on the principle that the immune system can be harnessed to detect and kill cancer cells, much in the same way that it goes ...

Cancer's gene-determined 'immune landscape' dictates progression of prostate tumors

January 12, 2018
The field of immunotherapy - the harnessing of patients' own immune systems to fend off cancer - is revolutionizing cancer treatment today. However, clinical trials often show marked improvements in only small subsets of ...

FDA approves first drug for tumors tied to breast cancer genes

January 12, 2018
(HealthDay)—The U.S. Food and Drug Administration on Friday approved the first drug aimed at treating metastatic breast cancers linked to the BRCA gene mutation.

Breast cancer gene does not boost risk of death: study

January 12, 2018
Young women with the BRCA gene mutation that prompted actress Angelina Jolie's pre-emptive and much-publicised double mastectomy are not more likely to die after a breast cancer diagnosis, scientists said Friday.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.