Lutein is a carotenoid pigment found in plant-based foods such as green and yellow vegetables and in dark green leafy vegetables, such as spinach, endive, kale, and broccoli.

The lutein comes from the extract of Tagetes erecta, better known as the marigold.

Carotenoids are natural pigments found in plants, algae, and some fungi. They are responsible for the yellow, orange, and red colors in foods like carrots, peppers, tomatoes, and corn. They are also present in green vegetables but are often "hidden" by the chlorophyll (leaf green).

Other carotenoids include beta-carotene, alpha-carotene, zeaxanthin, lycopene, astaxanthin, capsanthin, and violaxanthin.