Researchers from Pomeranian Medical University in Poland analyzed the effects of a probiotic containing nine bacterial strains and found a statistically significant decline in BMI and visible changes in hormone levels.
“Our study confirms the significant role of probiotics in hormonal regulation in women with PCOS,” they wrote in the journal Nutrients.
SanProbi provided the probiotic Barrier capsules and placebo capsule used but had no funding role in the study.
What is PCOS and how is it linked to the gut microbiome?
Caused by an imbalance of androgens, PCOS is a common hormonal condition that affects around 10% to 15% of the population.
Symptoms include irregular periods, weight gain, excessive hair growth and fertility issues, with the condition also linked to long-term health conditions such as type 2 diabetes and cardiovascular disease.
Research suggests that introducing selected bacterial cultures could help to regulate hormonal balance. Probiotics and synbiotics have therefore gained attention as potential interventions for PCOS by modulating the gut microbiota.
However, the authors of a 2024 meta-analysis concluded that the exact mechanisms, optimal bacterial strains, doses and duration of this treatment remained unclear.
Szydłowska et al. therefore set out to analyze whether a probiotic, containing Lactobacillus and Bifidobacterium, could improve hormonal parameters and BMI in a homogenous group of patients with PCOS.
Notable changes in hormone levels in the postbiotic group
Of the 50 women between the ages of 19 and 42 who were enrolled in the clinical trial, half were randomized to receive a twice-daily SanProbi Barrier capsule while the other half received a placebo. All the participants were considered overweight (BMI greater than or equal to 25 to 29.9 kg/m2).
The participants were monitored over a 12-week period, with serum samples taken during the early follicular phase of the menstrual cycle (days 3 to 5). Hormones were also measured at baseline and after the intervention period.
Statistically significant changes occurred only in the probiotic group, including a decrease in luteinizing hormone (LH), thyroid stimulating hormone (TSH) and androstenedione, and an increase in sex hormone-binding globulin (SHBG).
LH, which stimulates the ovaries to produce excessive androgens, can disrupt ovulation and contribute to symptoms such as irregular periods and infertility. Similarly, androstenedione acts as a precursor to testosterone, aiding in excessive androgen production.
Elevated TSH levels are also frequently observed in women with PCOS, with this hormone contributing to metabolic complications like insulin resistance.
Conversely, levels of SHBG, which binds to hormones such as testosterone, are typically lower in women with PCOS. This leads to higher levels of free testosterone, which also contributes to hyperandrogenism.
The researchers say these hormone changes may therefore have a “positive impact on these women’s health.”
Longer studies needed to confirm the results
Women in the intervention arm also saw a statistically significant reduction in BMI compared to the placebo group, suggesting that probiotic supplementation may also aid in weight management for women with PCOS.
“These findings are in contrast to those of the other researchers, who concluded that probiotics are not effective for weight loss,” the researchers wrote.
However, they warn that dietary measures were not controlled, and further studies which have increased controls, longer intervention durations and larger sample sizes are needed to confirm the findings.
“Given these limitations, the results should be interpreted with caution,” they concluded. “As the experiment was terminated after 12 weeks of probiotic therapy, it is not possible to determine whether this improvement was permanent or temporary.”
Source: Nutrients. doi: 10.3390/nu17030405. “Changes in Hormonal Profile and Body Mass Index in Women with Polycystic Ovary Syndrome After Probiotic Intake: A 12-Week Placebo-Controlled and Randomized Clinical Study”. Authors: I. Szydłowska, et al.
