Inclusion Criteria:

- Postmenopausal (self-reported cessation of menstruation 1 y prior to enrollment)

- If breast cancer survivor, all therapy completed at least 6 months prior to
enrollment

- Agreed to eat their normal diet, avoiding seaweeds and phytoestrogen-rich foods,

- Restricting alcoholic intake to #2 drinks (24 g alcohol)/wk -Continuing habitual
intake of vitamins, supplements, and medications during the study. -

Exclusion Criteria:

- No allergies to seaweed, soy, shellfish, or iodine

- No current use of tobacco;

- No thyroid dysfunction or treatment within the previous 5 y;

- Negative thyroid peroxidase antibodies as determined by screening;

- No hormone replacement therapy or for breast cancer survivors, no chemotherapy or
radiation treatments within the preceding 6 mo

- No history of cancer (other than breast cancer)

- No current gastrointestinal disorders or diabetes; omnivorous eating habits,
including meat and dairy products at least twice/wk

- No oral antibiotics, iodine containing medications, or corticosteroids treatment
within the previous 3 mo.