Pulse-based, TLC diets improve metabolic outcomes in PCOS
Women with polycystic ovary syndrome assigned a diet rich in chickpeas, lentils, dry beans and split peas as part of a lifestyle intervention were just as likely to experience an improvement in metabolic outcomes after 16 weeks as women with PCOS who adhered to the Therapeutic Lifestyle Changes, or TLC, diet, according to findings from a randomized controlled trial published in Clinical Endocrinology.
“In a diet intervention without prescribed energy restriction where aerobic exercise was recommended, and health care counseling was provided, both pulse-based and TLC diets yielded comparable benefits on ovarian function and hyperandrogenism,” Donna R. Chizen, MD, associate professor in the department of obstetrics and gynecology in the College of Medicine at the University of Saskatchewan, Canada, and colleagues wrote. “Our observations support the benefits of multidimensional healthy lifestyle interventions and add novel insights into the benefits of nutritionally balanced diets to improve the reproductive health of women with PCOS beyond temporary energy-restricted diets.”
In a single-blind, metformin-stratified, parallel-group study, Chizen and colleagues analyzed data from 64 women diagnosed with PCOS between April 2011 and June 2016 (mean age, 27 years). Researchers assigned participants to a pulse-based diet of two standard daily meals containing approximately 90 g split peas, 225 g chickpeas or beans, or 150 g lentils (n = 33), or a diet following TLC dietary guideline recommendations (n = 31), each for 16 weeks without energy restriction. Women assigned the TLC diet were counseled to consume low-fat cuts of meat, poultry and low fat or skim dairy as the main sources of protein and limit pulse consumption to purchase the foods prescribed by the TLC diet. All women were enrolled in a low-impact aerobics training program and received monthly health counseling. Researchers measured follicle numbers per ovary, ovarian volume, free androgen index (FAI) and menstrual cycle length at baseline and 16 weeks.
Within the cohort, 11 women in the pulse-based group and 13 women in the TLC group were prescribed metformin; researchers observed no group-by-time-by-metformin interactions for any outcomes.
From baseline to 16 weeks, researchers observed changes in follicle numbers per ovary (mean change, –10), ovarian volume (mean change, –2.7 mL), FAI (mean change, –3) and menstrual cycle length (mean change, –13 days) for both diet groups (P < .01 for all), without group-by-time interactions (P .13).
Additionally, researchers found that both diet groups maintained reduced ovarian volume, follicle numbers per ovary, FAI and menstrual cycle length at 6 months after intervention; however, decreased follicle numbers per ovary and FAI measurements at 16 weeks tended to revert to baseline levels at 1 year after the intervention for both diet groups (P .05 for all).
The researchers noted that longitudinal follow-up demonstrated that women experienced the greatest reproductive health benefits after 16 weeks of the intervention.
“Women exhibited a propensity for hyperandrogenism and ovarian dysmorphology 12 months post-intervention without the continual support of our health care providers who ensured adherence to healthy lifestyle behaviors,” the researchers wrote. “This observation coincided with weight regain, increased insulin resistance, and poor dietary and exercise behaviors as elaborated previously. Our results are consistent with previous observations about the propensity for obesity in women with PCOS and elucidate the need for further research to improve the engagement of women with PCOS with lifestyle modification that is sustainable.” – by Regina Schaffer
Disclosures: The authors report no relevant financial disclosures.