Lutein is a naturally occurring pigment classified as a carotenoid, a group of compounds responsible for the yellow and reddish colors found in many fruits and vegetables. This nutrient is important for human health. Eggs are a known dietary source of lutein, making them a subject of interest for their nutritional contributions.
What is Lutein and Why Does it Matter?
Lutein is a carotenoid often found alongside zeaxanthin. These two compounds are antioxidants that help protect the body’s cells from damage caused by unstable molecules known as free radicals. Oxidative stress from excess free radicals can contribute to aging and various health conditions.
Lutein and zeaxanthin are notably concentrated in the macula, a central part of the retina at the back of the eye, where they form macular pigment. This pigment plays a role in filtering harmful high-energy blue light, thereby reducing oxidative stress on the eyes and minimizing damage to photoreceptor cells. They also contribute to improved visual acuity and contrast sensitivity, particularly in low-light conditions. Studies suggest that consistent intake of these carotenoids can help slow the formation of cataracts and offer protection against age-related macular degeneration (AMD), a leading cause of vision loss. The human body does not produce lutein and zeaxanthin, so these nutrients must be obtained through dietary sources.
The Lutein Content in Eggs
One large egg contains about 252 micrograms of lutein, which includes zeaxanthin. This makes eggs a convenient source of this carotenoid.
Eggs are a beneficial source of lutein due to its high bioavailability. The fat in the egg yolk facilitates the absorption of fat-soluble carotenoids like lutein into the bloodstream. Research indicates that lutein from eggs is absorbed more readily by the body compared to lutein from some other plant-based sources, with studies showing significantly greater blood lutein responses after egg consumption. For instance, one study found that participants’ blood lutein levels were about three times higher after consuming eggs compared to the same amount of lutein from spinach or supplements. While leafy greens like kale and spinach contain higher absolute amounts of lutein per serving (e.g., cooked kale has about 23.5 mg per cup, and cooked spinach has about 20.2 mg per cup), the enhanced absorption from eggs contributes to their effectiveness as a dietary source.
Factors Affecting Lutein Levels in Eggs
The amount of lutein in an egg is largely influenced by the hen’s diet; hens fed diets rich in carotenoid-containing ingredients produce eggs with higher lutein concentrations. For example, incorporating yellow corn, alfalfa meal, or marigold petals into a hen’s feed can increase the lutein content in the egg yolk.
Increasing the inclusion of corn distillers dried grains with solubles (DDGS) in hen diets, for instance, has been shown to increase lutein concentrations in egg yolks. While the hen’s diet is the primary factor, other less significant variables such as management systems, environmental stress, or the hen’s age may also play a role, though information on these factors is less extensive.