Dietary diversity score is inversely related to the risk of polycystic ovary syndrome in Tehranian women: a case-control study

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder among women of reproductive age and is affected by various dietary factors. Therefore, this study aimed to investigate the relationship between dietary diversity score (DDS) and the risk of PCOS. Our case-control study was conducted in the summer and autumn of 2019 in Taleghani and Arash hospitals in Tehran, Iran. A total of 494 participants (203 cases and 291 controls) were included in the study. Thereafter, their demographic information, dietary intake, and anthropometric and physical activity assessments were gathered. A validated semi-quantitative food frequency questionnaire was then used to calculate the DDS by scoring 5 food groups. To evaluate the risk of PCOS in association with DDS, the subjects were categorized based on the quartile cut-off points of the DDS. The mean ± SD age of the participants in both the case and control groups was 28.98 ± 5.43 and 30.15 ± 6.21 years, while mean ± SD body mass index was 25.74 ± 5.44 and 23.65 ± 3.90 kg/m2, respectively. The comparison between the case and control groups indicated that total DDS was 5.19 ± 1.19 for the cases and 5.51 ± 1.19 for the controls. The comparison of DDS in the highest versus the lowest quartiles showed a decreased risk of PCOS (p < 0.05). We demonstrated an inverse association between DDS and PCOS compared with the control group. Furthermore, a higher DDS was significantly associated with a lower risk of PCOS (odds ratio = 0.40). Novelty: This is the first investigation on the relationship between DDS and PCOS. Results depicted an inverse relationship between DDS and PCOS.