Marigold Extract

Marigolds are grown commercially for yellow pigments used in poultry feed. Extraction concentrates those pigments from dried flowers. A carrier then turns the concentrate into a preparation for mixing into feed.^4,5

1. 01 // Source Marigold flowers Harvested flower heads supply the yellow pigments used to make meal and extract.
2. 02 // Process Dried and ground Processors dry the flower heads and grind them into meal before extracting the pigments.
3. 03 // Process Pigments extracted A solvent draws pigments from the meal, leaving concentrated oleoresin after the solvent is removed.
4. 04 // Process Carrier blended The oleoresin is blended with carriers and preservatives to make a commercial feed preparation.
5. 05 // Output Marigold extract The prepared extract reaches the feed mixer as a concentrated source of lutein.

1. 01

   Supplies lutein

   In the FDA notice, the proposed use in adult dog food was as a lutein source. The ingredient name alone does not state the finished food's lutein level.⁵

2. 02

   Fits a feed mix

   Processors blend concentrated oleoresin with carriers and preservatives to make a commercial preparation. The resulting ingredient differs from dried, ground marigold meal.^4,5

3. 03

   Draws on existing supply

   Poultry feed already uses marigold extracts to color skin and egg yolks. That market supplies concentrated pigments to feed makers, though it does not tell us their cost in dog food.⁴

How much FDA reviewed a proposed adult dog food use of up to 80 mg lutein per kg dry matter; typical extract inclusion is unpublished.⁵

1. Brands say

   Marigold extract is a concentrated lutein source

   Evidence

   1. Strong
   2. Some
   3. Thin
   4. None

   An EFSA analysis of 2 concentrated extracts found about 9 to 12% lutein on a dry basis. FDA reviewed an oleoresin specification of at least 125 g/kg total carotenoids. Neither figure fixes the strength of every preparation.^5,6

2. Brands say

   Marigold extract strengthens dogs' immune defenses

   Outruns the evidence

   Evidence

   1. Strong
   2. Some
   3. Thin
   4. None

   A 56 Beagle trial found stronger responses to immune challenges after 12 weeks of lutein. A separate 16 dog trial found higher counts of some immune cells but no change in lymphocyte proliferation. Neither measured whether dogs got sick less often.^1,2,7

3. Brands say

   Marigold extract protects dogs' eyesight

   Outruns the evidence

   Evidence

   1. Strong
   2. Some
   3. Thin
   4. None

   A 12 dog trial found improved retinal responses after 6 months on a supplement containing lutein and several other antioxidants. It cannot assign the effect to lutein, and it did not test marigold extract as protection against eye disease.^3,8

4. Critics say

   Marigold extract is just filler

   Outruns the evidence

   Evidence

   1. Strong
   2. Some
   3. Thin
   4. None

   FDA reviewed an oleoresin specification requiring at least 125 g/kg total carotenoids, and the notifier proposed it as a lutein source. It has a formulation purpose. Whether a particular food supplies a useful dose remains unknown.⁵