The Effect of Low Carbohydrate Diet on Polycystic Ovary Syndrome: A Meta-Analysis of Randomized Controlled Trials

Objective. To assess the effect of a low carbohydrate diet (LCD) on women with polycystic ovary syndrome (PCOS). Methods. Data from randomized controlled trials (RCTs) were obtained to perform a meta-analysis of the effects of LCD in PCOS patients. The primary outcomes included the changes in BMI, homeostatic model assessment for insulin resistance (HOMA-IR), and blood lipids, including total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C), follicle-stimulating hormone (FSH), luteotropic hormone (LH), total testosterone (T), and sex hormone-binding globulin (SHBG). Results. Eight RCTs involving 327 patients were included. In comparison with the control group, the LCD decreased BMI (SMD = −1.04, 95% CI (−1.38, −0.70), P<0.00001), HOMA-IR (SMD = −0.66, 95% CI (−1.01, −0.30), P<0.05), TC (SMD = −0.68, 95% CI (−1.35, −0.02), P<0.05), and LDL-C (SMD = −0.66, 95% CI (−1.30, −0.02), P<0.05). Stratified analyses indicated that LCD lasting longer than 4 weeks had a stronger effect on increasing FSH levels (MD = 0.39, 95% CI (0.08, 0.71), P<0.05), increasing SHBG levels (MD = 5.98, 95% CI (3.51, 8.46), P<0.05), and decreasing T levels (SMD = −1.79, 95% CI (−3.22, −0.36), P<0.05), and the low-fat and low-CHO LCD (fat <35% and CHO <45%) had a more significant effect on the levels of FSH (MD = 0.40, 95% CI (0.09, 0.71), P<0.05) and SHBG (MD = 6.20, 95% CI (3.68, 8.72), P<0.05) than the high-fat and low-CHO LCD (fat >35% and CHO <45%). Conclusion. Based on the current evidence, LCD, particularly long-term LCD and low-fat/low-CHO LCD, may be recommended for the reduction of BMI, treatment of PCOS with insulin resistance, prevention of high LDL-C, increasing the levels of FSH and SHBG, and decreasing the level of T level. Together, the analyzed data indicate that proper control of carbohydrate intake provides beneficial effects on some aspects of PCOS and may represent one of the important interventions improving the clinical symptoms of affected patients.

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Effect of high-intensity interval training on metabolic parameters in women with polycystic ovary syndrome: A systematic review and meta-analysis of randomized controlled trials

PLoS ONE ◽

10.1371/journal.pone.0245023 ◽

2021 ◽

Vol 16 (1) ◽

pp. e0245023

Author(s):

Isis Kelly dos Santos ◽

Fernando Antônio Santana de Souza Nunes ◽

Victor Sabino Queiros ◽

Ricardo Ney Cobucci ◽

Pedro Bruch Dantas ◽

...

Keyword(s):

Systematic Review ◽

Insulin Resistance ◽

Polycystic Ovary ◽

Meta Analysis ◽

Interval Training ◽

Controlled Trials ◽

High Intensity Interval Training ◽

Ovary Syndrome ◽

Randomized Controlled ◽

High Intensity Interval

Background Our aim was to assess the effect of high-intensity interval training (HIIT) on metabolic parameters and body composition in women with polycystic ovary syndrome (PCOS). Methods and analysis A systematic review and meta-analysis of randomized controlled trials was conducted using Embase, MEDLINE (via Ovid), PubMed, Sport Discus, Scopus, Web of Science, Cochrane Library and Google Scholar (advanced feature) up to September 2020. Two authors independently screened citations and determined the risk of bias and quality of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE). Meta-analyses were conducted using random effects model. Results Seven trials (n = 423) were included in the systematic review. The studies included HIIT interventions vs. moderate exercise or control groups. Most studies were small (average 32, range 24–110 participants) and of relatively short duration (10–16 weeks). The training intensity was performed between 90% and 95% of the maximum heart rate, three times a week, for at least 10 weeks. Insulin resistance, measured using homeostatic model assessment for insulin resistance (HOMA-IR), and body mass index (BMI) showed a significant decrease (MD −0.57; 95% CI, −0.98 to −0.16, p = 0.01), (MD −1.90, 95% CI −3.37, −0.42, p = 0.01) with moderate and high certainty of evidence, respectively. Conclusion Results support that HIIT alone is effective for reducing HOMA-IR and BMI in women with PCOS. However, evidence is limited to discern the effect of HIIT on other outcomes. Future studies with a longer duration (> 16 weeks), larger sample sizes and other outcomes are needed.

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The Role of Vitamin D Oral Supplementation in Insulin Resistance in Women with Polycystic Ovary Syndrome: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Nutrients ◽

10.3390/nu10111637 ◽

2018 ◽

Vol 10 (11) ◽

pp. 1637 ◽

Cited By ~ 16

Author(s):

Karolina Łagowska ◽

Joanna Bajerska ◽

Małgorzata Jamka

Keyword(s):

Systematic Review ◽

Insulin Resistance ◽

Vitamin D ◽

Polycystic Ovary Syndrome ◽

Fasting Glucose ◽

Polycystic Ovary ◽

Meta Analysis ◽

Controlled Trials ◽

Ovary Syndrome ◽

Randomized Controlled

Objective: To evaluate the effect of vitamin D supplementation (alone or with co-supplementation) on insulin resistance in patients with polycystic ovary syndrome (PCOS). Methods: We performed a literature search of databases (Medline, Scopus, Web of Knowledge, Cochrane Library) and identified all reports of randomized controlled trials (RCTs) published prior to April 2018. We compared the effects of supplementation with vitamin D alone (dose from 1000 IU/d to 60,000 IU/week) or with co-supplements to the administration of placebos in women diagnosed with PCOS. The systematic review and meta-analysis protocol was registered in the International Prospective Register of Systematic Reviews (Prospero) as number CRD42018090572. Main results: Eleven of 345 identified studies were included in the analysis; these involved 601women diagnosed with PCOS. Vitamin D as a co-supplement was found to significantly decrease fasting glucose concentrations and the HOMA-IR value. HOMA-IR also declined significantly when vitamin D was supplemented with a dose lower than 4000 IU/d. Conclusions: Evidence from RCTs suggests that the supplementation of PCOS patients with continuous low doses of vitamin D (<4000 IU/d) or supplementation with vitamin D as a co-supplement may improve insulin sensitivity in terms of the fasting glucose concentration (supplementation with vitamin D in combination with other micronutrients) and HOMA-IR (supplementation with vitamin D in continuous low daily doses or as co-supplement).

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