Low intakes of dietary fiber and magnesium are associated with insulin resistance and hyperandrogenism in polycystic ovary syndrome: A cohort study

Abstract

Background Women with polycystic ovary syndrome (PCOS) often have insulin resistance (IR) which may be worsened by obesity. The roles of dietary intake and activity are unclear. Our objectives were to determine whether (a) high caloric intake or inactivity explains obesity in PCOS, and (b) dietary composition is associated with PCOS phenotypes. Methods Eighty‐seven women with PCOS and 50 women without PCOS participated in this cohort study at a reproductive medicine center. Data collected included 3‐day food and physical activity records, anthropometrics, and metabolic and hormonal assays. Results Women with PCOS had increased body mass index (BMI) but similar caloric intake and activity to women without PCOS. There were no differences in protein, carbohydrates, fat, or glycemic load consumption, but women with PCOS consumed less fiber (medians: 19.6 vs. 24.7 g) and less magnesium (medians: 238.9 vs. 273.9 mg). In women with PCOS, those with IR consumed less fiber, less magnesium, and greater glycemic load than those without IR (medians: 18.2 vs. 22.1 g, 208.4 vs. 264.5 mg, 89.6 vs. 83.5). Fiber intake of women with PCOS was negatively correlated with IR, fasting insulin, glucose tolerance, testosterone, and dehydroepiandrosterone sulfate. Magnesium intake was negatively correlated with IR, C‐reactive protein, and testosterone, but positively correlated with HDL cholesterol. Fiber intake and BMI accounted for 54.0% of the variance observed in IR. Conclusions Obesity in women with PCOS could not be explained by overeating or inactivity. Increasing dietary fiber and magnesium intakes may assist in reducing IR and hyperandrogenemia in women with PCOS.

Dietary and Physical Activity Behaviors in Women with Polycystic Ovary Syndrome per the New International Evidence-Based Guideline

“…Our findings also corroborate existing evidence that women with PCOS meet recommended macronutrient distribution ranges [13,14,15,18,19,22]. We noted that our participants exhibited marginally low intakes of dietary fiber (24 g/d), and therefore mirrored the previous observations made by our group and Cutler et al (2019) in Canadian women [20,50]. Women with PCOS also had excessive sodium intake.…”

“…The possibility of excessive energy intake in women with PCOS is controversial. Some studies have reported similar energy intake and physical activity between women with and without PCOS [15,18,19,20], while others have identified a positive energy balance in women with PCOS, secondary to excessive caloric intake and sedentary lifestyle behaviors [10,13,21,22]. Improved diet quality has also been observed in women with PCOS, albeit in conjunction with increased energy intake and longer sitting intervals [14].…”

Reduced insulin resistance partly mediated the association of high dietary magnesium intake with less metabolic syndrome in a large Chinese population

“…Consistent with the result of our research, previous studies demonstrated an inverse association between dietary Mg intake and insulin resistance and a dose-effect relationship [21][22][23][24]. However, there is a lack of relevant research in Asian population and most Asian studies focused on the relationship between dietary Mg and the risk of diabetes, which were inconsistent.…”

<p>Reduced Insulin Resistance Partly Mediated the Association of High Dietary Magnesium Intake with Less Metabolic Syndrome in a Large Chinese Population</p>

“…Consistent with the result of our research, previous studies have demonstrated an inverse association and a dose-effect relationship between dietary Mg intake and insulin resistance. [22][23][24][25] However, there is a lack of relevant research in Asian populations, and most Asian studies have focused on the relationship between dietary Mg and the risk of diabetes, showing inconsistent results. Some studies showed that high dietary Mg intake could reduce Notes: Data are expressed as coefficients (95% CI).…”