Peer-Reviewed Pilot Study Shows Promise For Improvements in Premenstrual and Menstrual Symptoms Among Participants Using Seed Cycling Supplement with Chasteberry

In a single-arm study with 40 U.S. women enrolled, participants reported reductions in pain, bloating, and period-related sick days over two menstrual cycles

NEW YORK, Aug. 25, 2026 /PRNewswire/ -- Two Moons Health, a women's hormonal health company, in collaboration with Citruslabs, today announced the publication of its pilot clinical trial results in The Cureus Journal of Medical Science, part of Springer Nature, evaluating its two-phase seed cycling capsule supplement for menstrual symptoms.

Key Findings

Forty women participants in the U.S. were enrolled in the IRB-approved trial. After two cycles of the protocol over 56 days, the participants self-reported the following:

72% of the participants reported less premenstrual/menstrual pain
74% reduction in number of period-related sick days reported
67% of the participants reported less bloating and cramps
62% of the participants reported clearer skin, more stable mood and better sleep
87% of the participants wanted to continue using the product

Studying a Cycle-Synced Approach

Two Moons Health's system is inspired by seed cycling, an integrative nutritional practice in which four different seeds are consumed during different phases of the menstrual cycle. In addition to the seeds used in traditional seed cycling, the company also included the botanical ingredients chasteberry (vitex agnus-castus) and psyllium in the second phase.

The two-phased formulation incorporates the following finely ground organic ingredients in vegetable capsules: flaxseed and pumpkin seed in its ZEST capsule during days 1–14, followed by sesame seed, sunflower seed, chasteberry and psyllium in its ZEN capsule during days 15–28 of the menstrual cycle.

The publication of this pilot study contributes new and promising clinical data to an area of women's health that has historically received limited research: whether nutritional interventions timed to different phases of the menstrual cycle may support menstrual health and quality of life.

"Countless women adjust how they work, exercise, socialize, and plan their lives around symptoms which change throughout their cycles. Yet many supplements and functional products on the market are taking the same approach to every day of the month," said Terry Chang, founder and CEO of Two Moons Health. "We see it differently and wanted to ask: What if nutritional support varied as the body changed through each monthly cycle? Cycle-synced nutrition has gained significant consumer interest, but the research is still developing. We wanted to contribute to that growing evidence base with peer-reviewed scientific research."

"In my view, every woman has a story of being dismissed by the healthcare system. She has been told her symptoms are 'normal,' and told to come back when it's worse. So women are turning to certain dietary supplement brands for answers. That's a serious responsibility. Most brands point to studies on individual ingredients, meaning research that was never done on the product itself, often at different dosages. Two Moons chose to study their finished product in this pilot study. And yes, this initial study has limitations like all studies, but we have to start somewhere. In my opinion, that's what taking responsibility looks like, and we look forward to further research in this area," said Susanne Mitschke, CEO of Citruslabs, the third-party research organization which conducted the study.

"What is most encouraging to me in this pilot study is that we saw the participants report improvements across several measures that affect daily life - from pain and cramping to sleep, mood and missed days of work. These findings add to the growing body of research exploring how cycle-synced nutrition may support the menstrual cycle. While more comprehensive and robust research in larger populations will help us better understand these findings, I am encouraged by the potential of this approach and am excited to see it studied further," said Dr. Ulrike Kaunzner, co-founder and medical advisor for Two Moons Health.

Key Limitations

The authors note several limitations of this pilot study, including the study's small sample size, single-arm design (no placebo control) and reliance on self-reported outcomes.

The full peer-reviewed paper, "Symptoms of Premenstrual Syndrome In Women Receiving Seed Cycling Capsules With Chasteberry: A Single-Arm Clinical Trial Over Two Cycles," is available in Cureus at https://doi.org/10.7759/cureus.115036.

The study was sponsored by Two Moons Health.

About Two Moons Health

Two Moons Health is a women's hormonal health company developing plant-based nutritional products designed around the menstrual cycle. Its first product is ZEN and ZEST, a two-phase capsule system inspired by seed cycling and formulated to provide different nutritional support during different phases of the menstrual cycle.

Founded in New York City by lawyer and entrepreneur Terry Chang and neurologist Dr. Ulrike Kaunzner, Two Moons Health combines nutritional science, cycle awareness and modern consumer design to develop a new approach to menstrual wellness.

For more information, visit twomoonshealth.co

About Citruslabs

Citruslabs is a contract research organization specializing in clinical trials for consumer health and wellness brands across supplements, skincare, personal care, functional foods, pet health, and women's health. The company has conducted more than 500 IRB-approved studies for over 300 brands, helping companies substantiate product claims with real clinical evidence, from randomized controlled trials to pilot studies and consumer perception research. Citruslabs' decentralized study model makes rigorous, publishable clinical research accessible to brands of every size. A two-time Inc. 5000 honoree, Citruslabs is headquartered in the United States. For more information, visit citruslabs.com.

SOURCE Two Moons Health