Inclusion Criteria:
1. Female sex assigned at birth, ages 45-65 years inclusive at the time of consent.
2. Post-menopausal (≥12 consecutive months amenorrhea, STRAW+10 stage +1) OR peri-menopausal (STRAW+10 stages -2 or -1) at consent. PI to confirm staging at Screening.
3. Self-reported vasomotor symptoms ≥3 months' duration prior to Screening, averaging ≥4 episodes per 24-hour period over the 7 days prior to Screening.
4. Willing and able to consume the investigational product as directed (30 mL twice daily, empty stomach, 30 days).
5. Willing and able to complete daily eCOA entries in the study application and to wear the study wearable throughout the Treatment period.
6. Possession of (or willingness to use) a personal smartphone running iOS 16+ or Android 12+, with reliable daily internet access.
7. Resident of the Kansas City metropolitan area \[30- 45 mile radius\] and able to travel to Spectrum Clinical Research for a single onsite Participant Onboarding Visit.
8. Able to read, understand, and provide written informed consent in English at approximately an 8th-grade reading level.
9. Willing to abstain from initiation of any new HRT, menopause-related supplement, or other menopause-related therapeutic intervention for the study duration.
Exclusion Criteria:
1. Pre-menopausal status (STRAW+10 stage -3 or earlier).
2. Current pregnancy, planning pregnancy during the study, or breastfeeding.
3. Current use of any systemic or topical HRT. Required wash-out prior to Day 1: 30 days systemic and 30 days topical/local, aligned with the Screening period and the 30-day study duration; the PI may extend for an individual on documented clinical rationale per ICH E6(R3) 4.2.1.
4. Current use of any menopause-related dietary supplement within 30 days prior to Day 1, unless on a stable regimen ≥3 months and willing to maintain it unchanged (documented in medical history).
5. Known soy allergy or hypersensitivity to any component of Haelan 951 (Purified Water, Organic Cultured Soy Powder, Yeast, Salt).
6. History of estrogen- or progesterone-receptor-positive breast cancer; active malignancy of any type; or current systemic chemotherapy, immunotherapy, or radiation therapy.
7. Heavy alcohol use (≥3 alcoholic beverages/day on average, per NIAAA definitions).
8. Major surgical procedure or hospitalization within 90 days prior to Screening, or any unresolved condition that the PI judges would compromise safety or interpretation of endpoints.
9. Documented uncontrolled or unstable medical condition (e.g., uncontrolled cardiovascular disease; CKD stage 3b or worse; moderate-to-severe hepatic impairment; active autoimmune disease on systemic immunosuppression), established from medical history and PI clinical assessment.
10. Current use of medications with documented potential for clinically significant interaction with soy-derived foods (thyroid replacement unless dose-stable ≥6 weeks with 4-hour separation; oral anticoagulants on non-stable dose; MAOIs; tamoxifen or other hormone-modulating cancer therapies).
11. Current or recent (within 30 days) participation in another interventional clinical study.
12. Inability to provide informed consent (cognitive impairment, language barrier - materials are English-only - or other reason per PI judgment).
13. Other reasons judged by the PI, with documented rationale per ICH E6(R3) 4.2.1, to compromise safety, well-being, or scientific validity.
