Nutrient Patterns and Risk of Breast Cancer among Iranian Women: a Case- Control Study

Association between empirically derived nutrient patterns and breast cancer: a case-control study in a Middle Eastern country

PURPOSE

The risk of breast cancer (BC) and related mortality have increased in Middle-East countries during recent decades. The relationship between several nutrient intakes and the risk of BC has been investigated in several studies. However, few studies have estimated the effects of patterns of different nutrient intake on the risk of BC in this region.

METHODS

A total of 453 patients who were recently diagnosed with breast cancer and 516 healthy women participated in the current case-control study. To evaluate the dietary intakes, we used a validated 168-item food frequency questionnaire (FFQ) during the last year. Nutrient Patterns (NPs) were extracted through factor analysis (FA) of energy-adjusted twenty-six nutrients. The relationship between nutrient patterns and the risk of breast cancer in pre and post-menopausal women was estimated by multivariable regression.

RESULTS

Four major nutrient patterns were identified in the current study. The first nutrient pattern was rich in animal protein, retinol, riboflavin, pantothenic acid, cobalamin, and calcium. Higher saturated fatty acids (SFAs), mono-unsaturated fatty acids (MUFAs), polyunsaturated fatty acids (PUFAs), and trans fatty acids (TFAs), and lower intakes of niacin were observed in nutrient pattern 2. The third nutrient pattern was rich in fiber, potassium, and vitamin C. Nutrient pattern 4, was associated with higher intakes of vegetable protein, alpha-tocopherol, and magnesium. A significant inverse relationship was observed between adherence to nutrient pattern 3 and the risk of BC in all participants [odds ratio (OR) = 0.70, 95% confidence interval (CI): 0.50, 0.97, P = 0.03) and pre-menopausal women (OR = 0.59 (0.39-0.89), P = 0.01).

CONCLUSION

Decreasing odds of breast cancer were observed by adherence to a nutrient pattern high in dietary fiber, vitamin C, and potassium. Future prospective investigations are recommended to confirm these findings.

Vitamin D, Th17 Lymphocytes, and Breast Cancer

Simple Summary

The effect of vitamin D₃ on the development of breast cancer (favorable, ineffective, or even unfavorable) depends on many factors, such as age, menopausal status, or obesity. The immunomodulatory effect of vitamin D may be unfavorable in case of breast cancer progression. The effect of vitamin D on Th17 cells may depend on disease type and patients’ age. Our goal was to summarize the data available and to find indications of vitamin D treatment failure or success. Therefore, in this review, we present data describing the effects of vitamin D₃ on Th17 cells, mainly in breast cancer.

Abstract

Vitamin D₃, which is well known to maintain calcium homeostasis, plays an important role in various cellular processes. It regulates the proliferation and differentiation of several normal cells, including immune and neoplastic cells, influences the cell cycle, and stimulates cell maturation and apoptosis through a mechanism dependent on the vitamin D receptor. The involvement of vitamin D₃ in breast cancer development has been observed in numerous clinical studies. However, not all studies support the protective effect of vitamin D₃ against the development of this condition. Furthermore, animal studies have revealed that calcitriol or its analogs may stimulate tumor growth or metastasis in some breast cancer models. It has been postulated that the effect of vitamin D₃ on T helper (Th) 17 lymphocytes is one of the mechanisms promoting metastasis in these murine models. Herein we present a literature review on the existing data according to the interplay between vitamin D, Th17 cell and breast cancer. We also discuss the effects of this vitamin on Th17 lymphocytes in various disease entities known to date, due to the scarcity of scientific data on Th17 lymphocytes and breast cancer. The presented data indicate that the effect of vitamin D₃ on breast cancer development depends on many factors, such as age, menopausal status, or obesity. According to that, more extensive clinical trials and studies are needed to assess the importance of vitamin D in breast cancer, especially when no correlations seem to be obvious.

Association between Micronutrient Intake and Breast Cancer Risk According to Body Mass Index in South Korean Adult Women: A Cohort Study

This study investigated the association between micronutrient intake and breast cancer risk in South Korean adult women. This association was stratified according to body mass index (BMI) categories. Data from the Korean Genome and Epidemiology Study (KoGES) and the Health Examinee Study were analyzed. Altogether, 63,337 individuals (aged ≥40 years) completed the baseline and first follow-up surveys; 40,432 women without a history of cancer at baseline were included in this study. The association between micronutrient intake and breast cancer was determined by estimating the hazard ratio (HR) and 95% confidence interval (CI) using the Cox proportional hazard regression model. A stratified analysis by BMI (<25 kg/m2 and ≥25 kg/m2) was performed. The an analysis of 15 micronutrients and breast cancer risk revealed that none of the micronutrients were associated with breast cancer risk after adjusting for covariates. In obese women, the risk of breast cancer was significantly reduced in the group that consumed vitamin C more than the recommended level (HR = 0.54, 95% CI: 0.31−0.93) and vitamin B6 levels above the recommended level (HR = 0.48, 95% CI: 0.25−0.89). In obese women, exceeding the recommended daily intake levels of vitamin C and vitamin B6 was associated with a lower risk of breast cancer. However, other micronutrients were not associated with breast cancer risk in these women.