Fucoxanthin
Carotenoids
The golden-brown pigment of the large seaweeds, which masks their chlorophyll.
Only in BROWN seaweeds: neither nori nor dulse, which are red, provide it.
Effects and benefits
The golden-brown pigment that hides the green of wakame and kombu is one of the most abundant carotenoids on the planet. The gut turns it into fucoxanthinol, the form that circulates. In mice, it melted abdominal fat; in humans, trials remain too small to conclude.
Brown seaweeds and phytoplankton make colossal amounts of it: it captures the green and blue light that penetrates underwater, where red has disappeared.
In the gut, enzymes turn it into fucoxanthinol, then the liver into amarouciaxanthin: these are the forms found in the blood (Asai et al., 2004).
In obese mice, it reduced abdominal fat by activating a protein that burns energy as heat, UCP1 (Maeda et al., 2005). The few human trials are small: nothing is proven. Brown seaweeds are also very rich in iodine.
Sources: Asai et al., Drug Metab Dispos, 2004 · Maeda et al., BBRC, 2005