Fucoxanthin (see picture), an anti-obesity and anti-diabetic neutraceutical, is the major carotenoid found in marine brown seaweed.  Kazuo Miyashita, Hokkaido University, Japan, and colleagues show the biochemical mechanism for the anti-obesity and anti-diabetic activity of fucoxanthin.

Its’ anti-obesity activity is related to its chemical structure. The key is an essential allenic bond in the polyene chromophore. Nutrigenomic studies reveal that fucoxanthin induces uncoupling protein 1 (UCP1) expression in abdominal white adipose tissue (WAT) mitochondria, leading to the oxidation of fatty acids and heat production in WAT.

Fucoxanthin improves insulin resistance and decreases blood glucose levels by regulation of cytokine secretions in both abdominal adipose cells and macrophage cells infiltrated into adipose tissue.
Fucoxanthin has also shown anti-cancer activity for prostrate cancer by reducing cell viability through apoptosis.

• The allenic carotenoid fucoxanthin, a novel marine nutraceutical from brown seaweeds,
  K. Miyashita, S. Nishikawa, F. Beppu, T. Tsukui, M. Abe, M. Hosokawa,
  J. Sci. Food. Agric. 2011, 19, 1166–1174.
  DOI: 10.1002/jsfa.4353