It has been suggested that lutein and zeaxanthin can be considered conditionally essential nutrients because low serum levels or low dietary intake are associated with low macular pigment density and increased risk of Age related Macular Degeneration. However, there is not yet a well-established definition of lutein or zeaxanthin deficiency.
Authored by Dr Peter Engel in 2010, reviewed and revised by Jonas Wittwer on 23.05.2017