Clinical trial · Interventional
Dietary Seaweed and Early Breast Cancer: A Randomized Trial
- Source
- ClinicalTrials.gov
- Retrieved
- Sep 8, 2026
- Layer
- normalized (units and labels harmonized; values unchanged)
- Run
- ING-CLINICALTRIALS-20260908-000001
Summary
Brief summary (as posted)
Could daily consumption of seaweed help explain lower postmenopausal breast cancer (BC) incidence and mortality rates in Japan? This small proof of principle clinical trial was designed to test the idea that the same amount of seaweed normally eaten in Japan would induce metabolic changes when given to non-seaweed consuming healthy postmenopausal American women. The participants were given 10 capsules a day (about 1 tablespoon) for 3 months. During the first month the capsules contained placebo, the second month seaweed, and the third month placebo. We collected blood and urine samples after each treatment period and tested for changes in protein expression that might be related to consuming seaweed.
Conditions
Conditions (1)
Free-text conditions as registered, with the CancerIndex entity they were reconciled to and the match type.
| Condition (as posted) | Mapped entity | Match | Confidence |
|---|---|---|---|
| Seaweed Associated Changes in Healthy Subjects | — | UNRESOLVED | — |
Interventions
Interventions (3)
| Intervention | Type | Mapped drug | Match |
|---|---|---|---|
| Placebo | Other | — | UNRESOLVED |
| Placebo2 | Other | — | UNRESOLVED |
| Seaweed | Other | — | UNRESOLVED |
Design
Arms and outcomes
Arms (3)
- type
- PLACEBO_COMPARATOR
- label
- Placebo
- description
- 5 g/d placebo (maltodextrin)in 10 500-mg capsules for 1 month
- interventionNames
- Other: Placebo
- type
- EXPERIMENTAL
- label
- Seaweed
- description
- Seaweed (Undaria pinnatifida) given orally in ten 500-mg capsules for 1 month
- interventionNames
- Other: Seaweed
- type
- PLACEBO_COMPARATOR
- label
- Placebo2
- description
- 5 g/d placebo in 10 500-mg capsules for one month
Eligibility
Eligibility (as posted)
- Sex
- Female
- Minimum age
- 45 Years
- Maximum age
- 68 Years
Show eligibility criteria text
Inclusion Criteria: * Healthy * Postmenopausal (verified by follicle stimulating hormone (FSH) \[23.0-116 mIU/ml\] * Omnivorous eating habits (including meat and dairy products more than twice per week) * Limit alcoholic intake to ≤ 1 drink (12 g alcohol)/week Exclusion Criteria: * No allergies to seaweed, soy, shellfish or iodine * No current use of tobacco * No hormone replacement therapy * For BC survivors, no chemotherapy or radiation treatments within the preceding 6 months * No history of cancer (other than BC or squamous cell skin cancer) within the previous 20 years * No current gastrointestinal disorders or diabetes * No oral antibiotics taken in the previous 3 months
References
Publications (31)
- BACKGROUNDFunahashi H, Imai T, Tanaka Y, Tsukamura K, Hayakawa Y, Kikumori T, Mase T, Itoh T, Nishikawa M, Hayashi H, Shibata A, Hibi Y, Takahashi M, Narita T. Wakame seaweed suppresses the proliferation of 7,12-dimethylbenz(a)-anthracene-induced mammary tumors in rats. Jpn J Cancer Res. 1999 Sep;90(9):922-7. doi: 10.1111/j.1349-7006.1999.tb00836.x. PMID 10551319
- BACKGROUNDTeas J, Harbison ML, Gelman RS. Dietary seaweed (Laminaria) and mammary carcinogenesis in rats. Cancer Res. 1984 Jul;44(7):2758-61. PMID 6426785
- BACKGROUNDYamamoto I, Maruyama H, Moriguchi M. The effect of dietary seaweeds on 7,12-dimethyl-benz[a]anthracene-induced mammary tumorigenesis in rats. Cancer Lett. 1987 May;35(2):109-18. doi: 10.1016/0304-3835(87)90033-4. PMID 3107796
- BACKGROUNDHebert JR, Rosen A. Nutritional, socioeconomic, and reproductive factors in relation to female breast cancer mortality: findings from a cross-national study. Cancer Detect Prev. 1996;20(3):234-44. PMID 8769718
- BACKGROUNDKodama M, Kodama T, Miura S, Yoshida M. Nutrition and breast cancer risk in Japan. Anticancer Res. 1991 Mar-Apr;11(2):745-54. PMID 2064329
- BACKGROUNDParkin DM, Bray F, Ferlay J, Pisani P. Estimating the world cancer burden: Globocan 2000. Int J Cancer. 2001 Oct 15;94(2):153-6. doi: 10.1002/ijc.1440. No abstract available. PMID 11668491
- BACKGROUNDReddy BS, Cohen LA, McCoy GD, Hill P, Weisburger JH, Wynder EL. Nutrition and its relationship to cancer. Adv Cancer Res. 1980;32:237-345. doi: 10.1016/s0065-230x(08)60363-2. No abstract available. PMID 6258405
- BACKGROUNDShimizu H, Ross RK, Bernstein L, Yatani R, Henderson BE, Mack TM. Cancers of the prostate and breast among Japanese and white immigrants in Los Angeles County. Br J Cancer. 1991 Jun;63(6):963-6. doi: 10.1038/bjc.1991.210.