New Research on Diet and Endometrial Cancer Risk

Understanding Endometrial Cancer

Endometrial cancer originates in the endometrium, the lining of the uterus, and ranks as one of the most prevalent gynecological cancers in Western nations. In the United States alone, it impacts over 635,000 women, making it the fourth most common cancer among women in Europe. This type of cancer predominantly affects postmenopausal women, with a higher incidence in white women compared to black women.

Risk Factors for Endometrial Cancer

Endometrial cancer risk is influenced by both endogenous and exogenous factors related to estrogen. Key reproductive factors include an early onset of menstruation (menarche), delayed menopause, nulliparity (never having given birth), and the use of estrogen replacement therapy. Additional contributing factors include obesity, diabetes, and polycystic ovarian syndrome. These risk factors result in prolonged exposure of the endometrium to estrogens, which can become carcinogenic without sufficient progesterone. Hormonal imbalances, along with inflammation due to excess weight, may further elevate the risk of developing endometrial cancer.

Dietary Factors and Endometrial Cancer

Scientific studies have explored the link between dietary habits and endometrial cancer incidence, but previous findings have often been inconsistent. A recent investigation conducted in Northern Italy focused on the impact of fruit and vegetable consumption, adherence to a Mediterranean diet (MD), and the dietary inflammatory index (DII) on endometrial cancer risk. This case-control study, published in BioMed Central Cancer, involved 297 women diagnosed with endometrial cancer and two control groups totaling 307 women, all aged between 40 to 74 and residing in the same region.

Study Methodology

Researchers gathered data through a lifestyle questionnaire and a food frequency questionnaire, assessing various risk factors including oral contraceptive use, body mass index (BMI), physical activity, education, tobacco use, dietary habits, and reproductive history. Participants’ dietary habits were classified using an MD index based on adherence to Mediterranean dietary patterns and a DII index reflecting the inflammatory potential of the foods consumed. The MD index included eight dietary characteristics typical of Mediterranean diets, such as a high ratio of monounsaturated to saturated fats, increased consumption of legumes, cereals, fruits, and vegetables, moderate alcohol intake, and limited intake of meat, milk, and dairy products.

Findings on Diet and Endometrial Cancer Risk

The study revealed that women who consumed the highest amounts of fruits and vegetables had a significantly reduced risk of endometrial cancer, with fruit intake potentially offering protective benefits. Moreover, both moderate and high adherence to a Mediterranean diet was associated with approximately a 50% decrease in endometrial cancer risk. Foods with the lowest DII scores, including vegetables and whole grains, demonstrated protective effects, contrasting with high DII foods such as meat, saturated fats, and starches.

Mechanisms Behind Dietary Impact

The research underscored the protective influence of fruit and vegetable consumption on endometrial cancer risk. The authors emphasized that vegetable intake may bolster the immune system, enhance detoxifying enzymes, activate antioxidant mechanisms, and modulate steroid hormone levels. The Mediterranean diet, rich in phytoestrogens, could mimic or inhibit estrogen effects, providing anti-estrogenic benefits. Furthermore, this diet is abundant in antioxidants known for their anti-inflammatory properties and potential cancer risk reduction. An anti-inflammatory diet may help counteract chronic inflammation, a known risk factor for endometrial cancer.

Strengths and Limitations of the Study

A major strength of this research lies in the validated questionnaire utilized to assess exposure to risk factors, along with analyses adjusted for various confounders. However, the case-control design presents limitations, such as potential selection, information, and recall biases.

Conclusion: The Role of a Healthier Diet

This study provides compelling evidence for the protective benefits of high fruit and vegetable intake, adherence to the Mediterranean diet, and lower DII scores against endometrial cancer. The findings suggest a synergistic effect of various dietary components and biological mechanisms, highlighting the importance of diet in modulating endometrial cancer risk. Increasing vegetable consumption, following a Mediterranean diet, and maintaining a lower DII may yield significant health benefits.

Reference

Fulvio Ricceri et al., Diet and endometrial cancer: a focus on the role of fruit and vegetable intake, Mediterranean diet and dietary inflammatory index in the endometrial cancer risk. BMC Cancer (2017) 17:757.