Marc Joseph Nutrition - Blog

There’s a good amount of published research suggesting that the carotenoids (plant pigments) lutein and zeaxanthin may help to maintain vision and prevent the development of conditions such as age-related macular decline (AMD) and cataracts.

A recent study took a look at the potential benefit of lutein and zeaxanthin for skin health. Both nutrients are naturally found in the skin, and, as in the eye, are believed to have both antioxidant and light-filtering capability. In the double-blind, placebo-controlled study, researchers found that groups of individuals given oral and topical lutein/zeaxanthin were significantly less affected by exposure to ultraviolet (UV) radiation.

Specifically, after just two weeks, the groups given daily oral lutein/zexanthin supplementation (6 mg lutein, 0.6 mg zeaxanthin), topical lutein/zeaxanthin application (5% liquid), or both oral supplements and topical application, had improved their sensitivity to UV radiation by 4 times, 2 times, and 6 times, respectively.

Not only did the carotenoids protect the study participants’ skin from UV radiation damage, but the nutrients also improved the lipid (fat) content, hydration, and elasticity of the skin.

Sun exposure is the primary way for people to get the extremely important and often deficient vitamin D. At the same time, too much sun exposure can damage the skin. Good intake of lutein and zeaxanthin may help to offset this potential risk.

Sources of Lutein & Zeaxanthin

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Two recent studies in the Archives of Ophthalmology suggest that individuals with greater consumption of omega-3 fatty acids and higher vitamin D levels may be at lower risk for developing age-related macular degeneration (AMD), the most common cause of blindness for people over age 50.

There are two primary forms of AMD, the dry form, which is caused by loss of cells in the epithelial layer in the retina, and the wet (or neovascular) form, which is caused by abnormal blood vessel growth in the retina.

Omega-3

In the first study, researchers divided participants into five groups (quintiles) based on total omega-3 fat intake and found that the individuals in the top quintile were 39% less likely to develop wet AMD than people in the lowest quintile of intake. Scientists also looked at a specific omega-3 fatty acid (DHA - docosahexanoic acid), which is found in high concentration in the retina, and observed a 46% reduction in AMD risk when comparing the highest and lowest quintile of intake.

Additionally, fish intake positively correlated with reduced wet AMD risk in the study, but as discussed earlier, I would be reluctant to eat high levels of fish given the potential risk for toxin exposure. Vision disturbances are common in mercury poisoning cases. Contaminant-tested fish oil supplements are much preferred as a safer omega-3 source.

Interestingly, researchers found that high consumption of arachidonic acid (AA) was associated with a 54% increase in wet AMD risk. AA is an omega-6 fatty acid found in high quantities in red meat, dairy, and egg yolks, as well as metabolized from vegetable oils, such as corn and soybean oils commonly used in processed, packaged, and restaurant-prepared foods. This finding once again suggests that it is important to not only ensure adequate omega-3 intake, but also to moderate omega-6 intake, in order to manage inflammation. I addressed this topic in an earlier post.

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A recent Journal of Nutrition study looked at egg consumption and lutein and zeaxanthin levels. Researchers found that older adults (>60 years old) eating one egg a day increased their blood lutein and zeaxanthin levels increased 26% and 38%, respectively. And, importantly, serum concentrations of total cholesterol, LDL cholesterol, HDL cholesterol, and triglycerides were not affected.

Egg yolks are one of the best sources of both lutein and zeaxanthin, which are carotenoids that are very important in both eye and skin health. Increased intake of these compounds may help to reduce the risk of developing macular degeneration.

Additionally, egg yolks are a great source of choline, which is key in cell membrane function. Egg whites are also an excellent source of protein.

If possible, it’s best to get eggs from cage-free, organically fed chickens. Although getting good info on the different types of eggs available is not an easy task.