Fucoidan

Tier 3 — weak evidence · Cancer adjunct · Immunity

A complex sugar found in brown seaweed with immune-stimulating and anticancer properties in lab studies. Small human trials in cancer patients show improved immune markers when used alongside conventional treatment. Most evidence comes from cell and animal research rather than rigorous human trials. Generally well tolerated with no serious side effects.

Dose: 500–1,000 mg/day from Undaria or Fucus seaweed; most evidence is preclinical