AUTHOR=Qi Xiangying , Zhang Wenyan , Ge Mingxiu , Sun Qiang , Peng Lei , Cheng Wenke , Li Xuepeng 

TITLE=Relationship Between Dairy Products Intake and Risk of Endometriosis: A Systematic Review and Dose-Response Meta-Analysis

JOURNAL=Frontiers in Nutrition

VOLUME=Volume 8 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2021.701860

DOI=10.3389/fnut.2021.701860

ISSN=2296-861X

ABSTRACT=Objective: Diet lifestyle can influence the risk of endometriosis. Therefore, we conducted a systematic meta-analysis to investigate the association between dairy products and the risk of endometriosis. Besides, we performed a dose-response meta-analysis to evaluate the amount of dairy intake affecting the risk of endometriosis.
Methods: Relevant studies were searched from Pubmed, Embase databases, Cochrane Library, and Web of Science from the inception to November 6th, 2020. Also, the dose-response meta-analysis was conducted. All the pooled results were performed by risk ratios (RRs).
Results: Finally, seven high-quality studies were included in the present meta-analysis. Total dairy intake was inversely associated with the risk of endometriosis, and the risk of endometriosis tended to decrease with a decrease in the risk of endometriosis when dairy products intake was over 21servings/week (RR0.87, 95%CI0.76-1.00; pnonlinearity=0.04). Similarly, people who consumed more than 18 servings of high-fat dairy products per week had a reduced risk of endometriosis (RR 0.86, 95%CI0.76-0.96). When stratified-analyses were conducted based on specific dairy product categories, it indicated that people with high cheese intake might have a reduced risk of endometriosis (RR 0.86, 95%CI0.74-1.00). Other specific dairy products such as whole milk (RR 0.90, 95%CI0.72-1.12), reduced-fat/skim milk (RR0.83, 95%CI0.50-1.73), ice cream (RR0.83, 95%CI0.50-1.73), and yogurt (RR0.83,95%CI0.62-1.11) have not shown significant evidence of an association with the risk of endometriosis. However, there is a higher risk of endometriosis in the females with high butter intake compared to females with low butter intake (1.27, 95%CI1.03-1.55). 
Conclusions: Overall, dairy products intake was associated with a reduction in endometriosis, with significant effects when the average daily intake≥3 servings. When analyzed according to the specific type of dairy product, it was shown that females with higher high-fat dairy and cheese intake might have a reduced risk of endometriosis. However, high butter intake might be associated to the increased risk of endometriosis. More future studies are needed to validate and add to this finding.