Question: what is the difference between zeaxanthin and meso-zeaxanthin?
Answer: Unlike lutein and zeaxanthin, meso-zeaxanthin is a non-dietary carotenoid that is not found in the serum of humans, but only in the retina (specifically the macula). Scientists have found evidence that suggests meso-zeaxanthin is produced in the retina from lutein via an isomerization process.