Bladderwrack is a type of seaweed or kelp available as a supplement in pill form. Bladderwarck has sulfated polysaccharides and other antioxidants. Fucoidan is one of the active components which has a number of physiological effects.

Bladderwrack benefit
Bladderwrack may be helpful in women who have excessive estrogen secretion or predisposed to estrogen sensitive conditions. Additional research is likely to reveal a number of health benefits from the use of bladderwrack.

Lung cancer
PLoS One. 2012. Fucoidan from seaweed Fucus vesiculosus inhibits migration and invasion of human lung cancer cell via PI3K-Akt-mTOR pathways.

Bladderwrack Research studies, influence on menstrual cycle
The effect of Fucus vesiculosus - bladderwrack - an edible brown seaweed, upon menstrual cycle length and hormonal status in three pre-menopausal women: a case report.
BMC Complement Altern Med. 2004. School of Public Health, Molecular Epidemiology and Toxicology Laboratory, University of California, Berkeley, CA
Rates of estrogen-dependent cancers are among the highest in Western countries and lower in the East. These variations may be attributable to differences in dietary exposures such as higher seaweed consumption among Asian populations. The edible brown kelp, Fucus vesiculosus ( bladderwrack ), as well as other brown kelp species, lower plasma cholesterol levels. Since cholesterol is a precursor to sex hormone biosynthesis, kelp consumption may alter circulating sex hormone levels and menstrual cycling patterns. In particular, dietary kelp may be beneficial to women with or at high risk for estrogen-dependent diseases. To test this, bladderwrack was administered to three pre-menopausal women with abnormal menstrual cycling patterns and/or menstrual-related disease histories. These pilot data suggest that dietary bladderwrack may prolong the length of the menstrual cycle and exert anti-estrogenic effects in pre-menopausal women.

Treatment of human skin with an extract of Fucus vesiculosus changes its thickness and mechanical properties.
J Cosmet Sci. 2002.
The effects of topical application of an aqueous extract of bladderwrack on the thickness and the mechanical properties of human skin was performed. A gel formulation that included 1% of the bladderwrack extract was applied topically to human cheek skin twice daily for five weeks. A significant decrease in skin thickness was elicited, as was a significant improvement in elasticity. In cheek skin, the thickness normally increases and the elasticity usually decreases with age. These results suggest that the bladderwrack extract possesses anti-aging activities and should be useful for a variety of cosmetics.

Interactions with other dietary supplements
Q. Can bladderwrack herb be taken the same day as AHCC?
   A. I don't see any reason why bladderwrack can't be combined with this supplement.

Q. Is a bladderwrack supplement effective for weight loss?
   A. I have not seen any good research that a bladderwrack supplement is effective by itself for weight loss. See weight loss pill for supplements that could help.