Ladies, Go Light on the Dairy

Breast cancer survival affected by high fat dairy products

(RxWiki News) Who doesn’t love a bowl of ice cream? Or cheese? What about a dollop of half and half to make that cup of coffee creamy and luscious? You may love these things, but your body might not.

High-fat dairy foods can impact the health of women who’ve beaten breast cancer.

A new study found that eating these foods regularly – once a day – can increase a breast cancer survivor’s odds of dying years later.

"Choose low-fat or plant-based dairy foods."

Candyce H. Kroenke, ScD, MPH, staff scientist with the Kaiser Permanente Division of Research, led the study – the first to examine the relationship between high-fat and low-fat dairy consumption following breast cancer diagnosis and long-term survival.

“A take-away message from my study is that women who consumed the highest amounts of high-fat dairy had an elevated risk of dying from their breast cancer," Dr. Kroenke told dailyRx News. 

"As far as recommendations, the findings from this study would be consistent with shifting to low-fat dairy (or to unsweetened plant-based foods/milks).” 

The problem is the amount of estrogen found in high-fat dairy products. Estrogen is a hormone that drives the majority of breast cancers. This hormone exists mostly in fat. Therefore, more estrogen is found in high-fat than in low-fat dairy products.

Researchers looked at the records of 1,893 women from the Life After Cancer Epidemiology (LACE) study diagnosed with early-stage invasive breast cancer from 1997 to 2000. These women had all completed the Fred Hutchinson Cancer Research Center Food Frequency Questionnaire shortly after diagnosis and six years later.

The women were asked what types of dairy products they consumed, how often, portion sizes and whether the foods were full-, low- or non-fat.

Of the study members, 349 saw the cancer return, and 372 women (19.6 percent) died during a median follow-up of 11.8 years. Breast cancer was the cause of death for 189 women – 1 percent of the total group.

The study found that women who had one or more servings of high-fat dairy a day had a 64 percent higher risk of dying from any cause and a 49 percent increased risk of dying from breast cancer within 12 years of being diagnosed with the disease.

High-fat dairy products included cream, ice cream, whole milk, full-fat cheese and yogurt, whole condensed or evaporated milk, pudding, custard and flan. The study found that low-fat dairy did not affect survival.

“High-fat dairy foods are not recommended for breast cancer survivors because the major type of fat in these foods is saturated fat, which is linked with increased blood cholesterol and higher risk for cardiovascular disease," Cheryl L. Rock, PhD, RD, professor of medicine at the University of California, San Diego, told dailyRx News.

“Low-fat and nonfat dairy foods are a better choice and can provide calcium, vitamin D (in the case of fortified milk), high-quality protein and other nutrients in the diet,” Dr. Rock said.

Christopher O. Ruud, MD, breast cancer specialist at the Austin Cancer Centers, told dailyRx News, ""This is an interesting epidemiologic study. While it is not certain that high fat dairy promotes recurrence, it makes sense to use low fat dairy. According to the NCHPAD [National Center on Physical Activity and Disability],"Low-fat dairy options include: low-fat cream cheese, low-fat cottage cheese, skim milk, reduced fat sour cream, one-third less fat cream cheese, and low-fat and non-fat yogurt."

The LACE study is one of several studies Kaiser Permanente investigators are undertaking to look at the role of lifestyle factors (diet, exercise, social support) in breast cancer survival.

Findings from this study were published March 14 in the Journal of the National Cancer Institute. The National Cancer Institute of the National Institutes of Health funded this study. No conflicts of interest were reported.

Review Date: 
March 14, 2013