Eggs and Ovarian Cancer

by Michael Greger, M.D.

Ovarian cancer has earned a reputation as a silent killer, because it eludes early detection and has an alarming fatality rate that hasn't really changed in over 50 years. Currently in the U.S. it's the fifth leading cancer cause of death for women. In other areas of the world, though, rates are as much as 5-fold lower.[26] When women move from low risk countries (like Japan) to the U.S. their risk jumps up, suggesting environmental rather than genetic factors are culpable for the wide variation in risk.[27] Canadian researchers recently published a study of dietary factors that may be to blame.

"In summary," the researchers conclude, "our population-based case-control study found that women with higher consumption of dietary cholesterol and eggs were at an increased risk of ovarian cancer." On the other hand, the food that was the most powerful protector against ovarian cancer in this study were the cruciferous vegetables, like broccoli, kale, collards, etc.[28]

Because estrogen is synthesized from cholesterol, researchers speculate that women with cholesterol in their diet may have higher levels of circulating hormones that may increase cancer risk. Other researchers propose that it may not be the cholesterol itself, but instead the organochlorine pesticides which concentrate in animal fats.[29]

Eggs are one of the most concentrated sources of cholesterol in the food supply, but cholesterol is found in all animal foods. Cholesterol is made by the liver, and since plants don't have little livers, the only source of cholesterol in the human diet is food derived from animals.

Women may be able to protect their eggs (and their lives) by not eating the eggs of chickens.

REFERENCES

26 Seminars in Surgical Oncology 10(1994):242.
27 Cancer Research 35(1975):3240.
28 Cancer Epidemiology, Biomarkers and Prevention 13(2004):1521.
29 Cancer Epidemiology, Biomarkers and Prevention 11(2002):1112.