Does drinking milk increase the risk of ovarian cancer?
Medicineonline.com, a website about medical and health news, included an article on Aug. 5, 2005 titled "High Milk Intake May Boost Ovarian Cancer Risk," which stated:
"Three, large, well-designed studies in which dietary intake as assessed among cancer-free women who were followed up over time to see who developed ovarian cancer showed an increased risk of ovarian cancer among women with high intakes of milk and lactose...
If women took in a daily increase of 10 grams of lactose, about the amount in one glass of milk, their risk of ovarian cancer increased by 13 percent...
Exactly how the dairy foods may boost risk isn't known, but lactose produces galactose and glucose, and galactose has been thought to increase the risk by direct toxicity to the ovarian germ cells."
Susanna Larsson, PhD, researcher in the Unit of Nutritional Epidemiology at the Karolinska Institute in Sweden, et al., concluded in their study titled "Milk and Lactose Intakes and Ovarian Cancer Risk in the Swedish Mammography Cohort," published in the American Journal of Clinical Nutrition," in Nov. 2004:
"Women who consumed greater than or equal to four servings of total dairy products per day had a risk of serous ovarian cancer twice that of women who consumed less than 2 servings per day. We observed a positive association between lactose intake and serous ovarian cancer risk.
Our data indicate that high intakes of lactose and dairy products, particularly milk, are associated with an increased risk of serous ovarian cancer but not of other subtypes of ovarian cancer."
Kathleen Fairfield, MD, PhD, Research Scientist and Staff Physician at Maine Medical Center, et al., reported in her Feb. 2004 paper "A Prospective Study of Dietary Lactose and Ovarian Cancer" in the International Journal of Cancer:
"Lactose intake appeared positively associated with epithelial ovarian cancer, with a 40% increase in risk for women in the highest category of cumulative average intake compared to the lowest...
For women with serous ovarian cancer [a subtype of epithelial ovarian cancer], we observed a 2-fold increase in risk for those with the highest lactose intake compared to the lowest...
When we evaluated dairy foods, skim or low-fat milk consumption was modestly associated with overall ovarian cancer risk when cumulatively updated consumption was considered. For serous ovarian cancers, women consuming one or more servings of skim and low-fat milk daily had a 69% higher risk... In analyses, combining servings of all types of milk (skim, low-fat milk or whole milk), we found a 55% higher risk of serous cancers."
Lawrence Kushi, ScD, Associate Director for Etiology and Prevention Research in the Division of Research at Kaiser Permanente, et al., explained in their Jan. 1999 paper "Prospective Study of Diet and Ovarian Cancer" in American Journal of Epidemiology:
"A positive association was found between the intake of dairy products and incidence of ovarian cancer... In particular, increasing consumption of skim milk was associated with a greater risk [of ovarian cancer]...
The associations with dairy foods and lactose suggest that lactose may play a role in the etiology [development] of ovarian cancer. That intake of calcium, skim milk, and cheeses appeared to be associated with an increased risk, while whole milk, cream, and saturated fatty acids did not, also suggests that the fat component of dairy products is unlikely to be responsible for the observed increased risk of ovarian cancer associated with dairy foods."
Nutraingredients.com, a website about nutrition, included an article on Mar. 9, 2002 titled "Dairy Foods Could Lower Ovarian Cancer Risk," which stated:
"Women who consume a large amount of dairy foods may reduce their risk of ovarian cancer... Women with the highest intake of dairy products were 54 per cent less likely to be diagnosed with ovarian cancer than those who ate the lowest amounts of dairy products...
Women who consumed the most dairy products overall, including low-fat and skimmed milk, were the least likely to be diagnosed with ovarian cancer. Ethnicity had no effect on the results...
The [research] team explained that it was both the high intake of calcium and lactose that lowered the cancer risk. Lactose, the sugar in dairy foods, is thought to increase calcium absorption and promote the growth of bacteria that fight cancer-causing chemicals."
Sai Yi Pan, MD, Senior Epidemiologist at the Public Health Agency of Canada, et al., stated in their Sep. 2004 paper "A Case-Control Study of Diet and the Risk of Ovarian Cancer" in Cancer Epidemiology Biomarkers and Prevention:
"We saw no
evidence of any pattern of association of ovarian cancer risk with...
any dairy product, including all milk, low-fat milk, low-fat and skim
milk, cheese, and ice cream... Our study found that several dietary
factors were associated with ovarian cancer risk... However, [our
study] failed to find an association with any dairy products."
Marc T. Goodman, PhD, MPH, Researcher at the Cancer Research Center of Hawaii, et al., reported in their July 2002 paper "Association of Dairy Products, Lactose, and Calcium with the Risk of Ovarian Cancer" in the American Journal of Epidemiology:
"Dietary calcium has been reported to be inversely related to breast cancer and colon cancer and positively related to prostate cancer. Two previous epidemiologic studies examined the potential association of calcium with ovarian cancer.
Consumption of all dairy products, all types of milk, and low-fat milk was significantly inversely related to risk of ovarian cancer, but consumption of whole milk was not. In summary, we found that women who consume higher quantities of calcium and lactose were at significantly decreased risk of epithelial ovarian cancer."
Jeanine M. Genkinger, PhD, Assistant Professor of Genetics and Epidemiology in the Department of Oncology at Georgetown University Medical Center, et al., wrote in their Feb. 2006 article "Dairy Products and Ovarian Cancer: A Pooled Analysis of 12 Cohort Studies" in Cancer Epidemiology Biomarkers and Prevention:
this pooled analysis of 12 cohort studies that prospectively assessed
the association between diet and ovarian cancer risk, no statistically
significant associations were observed for milk or calcium intake... We
found no association between intakes of several specific dairy foods,
dietary calcium, total calcium, and dietary and supplemental vitamin D
and risk of ovarian cancer in this pooled analysis of 553,217 women."