In Christianity, Easter commemorates the resurrection of Jesus. While Easter Sunday and the days leading up to it remain a holy celebration to some, many associate the holiday with more secular symbols like the start of spring, cute bunnies, delicious jellybeans, and, of course, bright colored eggs. In honor of the Easter holiday, let’s take a look at what is known about eggs and cancer risk.
In general, most consider eggs a somewhat healthy food, and indeed, they are packed with vitamins, calcium, zinc, and selenium. Eggs contain quality protein, and while high in cholesterol, those consuming eggs regularly exhibit increased high-density lipoprotein (HDL), the “good” cholesterol. Despite the health benefits, some studies have raised concern that egg consumption could also increase the risk of certain types of cancer. So, will Easter eggs impact cancer risk? The short answer is...unclear.
One study found that healthy men who consumed at least 2.5 eggs per week had an 81% increased risk of lethal prostate cancer than men who consumed less than 0.5 eggs per week. Links between eggs and prostate cancer may be facilitated by choline, an essential nutrient required for metabolism and cell membrane signaling that can also promote proliferation of prostate cancer cells. While choline is present in many foods, one egg contains more than a quarter of the daily value recommended by the CDC. When examining choline intake, men consuming the highest levels had a 70% increased risk of lethal prostate cancer.
In addition to linking eggs to prostate cancer, a meta-analysis demonstrated elevated ovarian and breast cancer risk in those with high egg consumption. The authors of this study suggest that in addition to the negative impact of choline, a bi-product of cholesterol could act as an estrogen receptor agonist, thus promoting cancer development in hormone-related breast and prostate cancers. Another study publishing links between breast cancer and egg consumption found an even higher risk for post-menopausal women. However, the data related to breast cancer is inconsistent as another study has shown that egg consumption reduces the risk of breast cancer.
A large meta-analysis of over 40 independent studies linked egg consumption and gastrointestinal (GI) cancers, including colon, stomach, and colorectal. Another study investigated egg consumption and bladder cancer. Interestingly, this study indicated that only consumption of fried, but not boiled, eggs increased cancer risk.
In total, no large-scale randomized studies have investigated the impact of egg consumption on cancer risk. While some studies indicate associations between cancer and eggs, these studies have not consistently corrected for confounding variables, and not all thoroughly differentiate between various ways of cooking eggs. Until more is known in this area, the many health benefits of eggs may outweigh the risks for many.
Sources: J Int Med, Asian Pac J Cancer Prev, Can Prev Res, Am J Clin Nutr, Be J Nutr, Breast Cancer, Breast Cancer Res, Eur J Nutr, Nutr Cancer