Association of Dairy Products, Lactose, and Calcium with the Risk of Ovarian Cancer

Abstract

Epidemiologic findings have been inconsistent regarding the association of dietary fat, dairy products, and lactose with risk of ovarian cancer. The authors conducted a case-control study in Hawaii and Los Angeles, California, to examine several dietary hypotheses regarding the etiology of ovarian cancer in a population with a broad range of dietary intakes. A total of 558 patients with ovarian cancer diagnosed in 1993-1999 and 607 controls were interviewed regarding their diet. Consumption of all dairy products, all types of milk, and low-fat milk, but not consumption of whole milk, was significantly inversely related to the odds of ovarian cancer. Similar inverse gradients in the odds ratios were obtained for intakes of lactose and calcium, although these nutrients were highly correlated (r = 0.77). The odds ratio for ovarian cancer was 0.46 (95% confidence interval: 0.27, 0.76) among women in the highest quartile of dietary calcium intake versus the lowest (p for trend = 0.0006). The significant dietary association was limited to dairy sources of calcium (p for trend = 0.003), although a nonsignificant inverse gradient in risk was also found in relation to calcium supplement intake. These results suggest that intake of low-fat milk, calcium, or lactose may reduce the risk of ovarian cancer.

Dairy consumption and ovarian cancer risk in the Netherlands Cohort Study on Diet and Cancer

“…For consumption of yoghurt, a positive association with serous ovarian cancer was reported from the Nurses' Health Study, and for consumption of hard cheese the risk of all epithelial ovarian tumours was decreased with higher consumption (Fairfield et al, 2004). The results of our prospective cohort study are in accordance with results from previous case -control studies (Cramer et al, 2000;Goodman et al, 2002) in showing no effect of higher yoghurt or cheese consumption on ovarian cancer risk. Lactose or dairy fat has been considered as the explanation for earlier findings of increased ovarian cancer risk with higher consumption of dairy products.…”

“…Our study results however suggest no association with lactose intake or might even indicate an inverse association. Inverse associations between lactose intake and ovarian cancer have previously been reported from casecontrol studies (Herrinton et al, 1995;Goodman et al, 2002). Differences in level of lactose intake may have contributed to the discrepancy among cohort studies, since the Netherlands has a high consumption of dairy products.…”

“…Higher consumption of skim milk was also found to increase the risk of ovarian cancer in the Iowa Women's Health Study (Kushi et al, 1999). However, results from case -control studies have been inconsistent, some reporting no association with whole milk (Cramer et al, 2000;Goodman et al, 2002) or skim or low-fat milk (Cramer et al, 2000), whereas a positive association with whole milk and a negative association with skimmed milk have also been found (Mettlin and Piver, 1990;Webb et al, 1998). For consumption of yoghurt, a positive association with serous ovarian cancer was reported from the Nurses' Health Study, and for consumption of hard cheese the risk of all epithelial ovarian tumours was decreased with higher consumption (Fairfield et al, 2004).…”

“…The results from case -control and prospective cohort studies regarding milk consumption and ovarian cancer risk have been inconsistent (Mettlin and Piver, 1990;Webb et al, 1998;Kushi et al, 1999;Cramer et al, 2000;Goodman et al, 2002;Fairfield et al, 2004;Larsson et al, 2004;Qin et al, 2005).…”

“…With the exception of two case -control studies that reported a protective effect (Herrinton et al, 1995;Goodman et al, 2002), most studies found no statistically significant effect of high lactose intake on overall ovarian cancer risk (Engle et al, 1991;Webb et al, 1998;Kushi et al, 1999;Cramer et al, 2000;Cozen et al, 2002;Fairfield et al, 2004). On the other hand, for serous epithelial ovarian tumours, a positive association with lactose intake has been observed (Fairfield et al, 2004;Larsson et al, 2004).…”