A Super Nutrient You Should Be Consuming
The comic strip called Popeye made its first appearance more than 100 years ago and turned into an iconic cartoon series. Initially, in order to summon super strength, Popeye would rub the head of a whiffle hen before transforming into the great knock down superhero.
Thankfully, the whiffle hen head rubbing ended and was replaced with eating a can of spinach. Spinach at the time had been identified as a superfood due to its high Vitamin A content. However, one of the strongest constituents of spinach had yet to be identified which was a chemical called lutein.
Lutein received its first notoriety many years later in the 1980’s as it was identified to be a part of the protective pigment that sat on the retina of the eye. The eyes were only the beginning of where lutein was found to be helpful.
What is Lutein?
Lutein is often extracted from the Marigold Flower
Lutein is classified as a carotenoid which is in the same family as Vitamin A. Other common carotenoids are zeaxanthin found in orange peppers and egg yolks, beta carotene found in carrots, lycopene found in tomatoes and astaxanthin found in krill oil. All are fat soluble and that means in a practical sense, that they should be ingested with a dietary fat source.
As a rule, all are antioxidants and anti-inflammatories. Lutein, for example lowers blood inflammatory markers such as TNF-alpha, interleukin-6, and interleukin-1-beta.  Having less inflammation with the help of lutein is desirable and may help arteries to have less buildup and lower the incidence of cardiovascular disease.  Lutein does lower oxidation levels in a type of cholesterol called LDL which has been implicated in cardiovascular disease.
Lutein has been popular and mostly associated with the eyes. It concentrates on the nerves of the retina protecting the eyes from oxidation and filters out damaging blue light.  Generally, lutein is more abundant around the perimeter of the retina and its isomer compound called zeaxanthin is more abundant to the middle. Oxidation, when not mitigated by lutein, is thought to precede eye disorders such as cataracts, macular degeneration, retinal detachment, and loss of vision. Lutein improves blood circulation to the eyes while reducing eye pressure.  Anytime you can increase circulation to any part of the body, it usually comes with positive effects.
The Background with Lutein in the Brain
Even though lutein is generally not the highest carotenoid consumed in the diet, it does account for the highest concentration of all carotenoids in the brain. The brain concentration of lutein does correlate with healthier brains in older individuals.
The connection between the retina in the eyes and the brain is the density or concentration of nerves as both organs have a high nerve density. Lutein integrates into fatty layers of cell membranes, mitochondrial membranes and with the covering of the nerves called myelin.  Myelin is the biological protective covering of nerves that helps keep nerves healthy and strong.
You may be thinking, OK I can take this as part of my older person vitamin mix, but not sure I need to know about this now… Well, there was a study that may change your mind…
A study was done using 29 males and 22 females with 14 in the placebo group and 37 receiving 12mg of lutein and 2mg of zeaxanthin daily for a year. The ages of the participants ranged from 18 to 30 years old and were considered healthy individuals.
The researchers were incredibly surprised at the results because significant increases in brain function were thought to be unlikely in this age group.
After a year had passed, aspects of brain function such as:
all improved significantly over the placebo group. Both lutein and zeaxanthin also improved in concentration levels dramatically in the retinas of the eyes. 
Another study found that lutein improved temporal processing speed to cognition which means in a matter of speaking that some of that quicker wit came back. 
Lutein and Performance
As if brain improvement was not enough reason to consider lutein as part of a supplement regimen, lutein does some interesting aspects to improve athletic performance.
According to a study, people get more active with higher lutein consumption. The researchers found a 26% higher activity level and a 10% reduction in sedentary time when plasma lutein levels doubled with 21mg of lutein consumption daily. Researchers found the enzyme AMPK and a carnitine enzyme called carnitine palmitoyltransferase 1 [CPT1] are activated with lutein consumption and exercise.  AMPK stimulates muscle cells to develop and the carnitine enzyme assists in fat burning. Lutein can help with getting more active, muscle building, fat burning and help fat cells get smaller.
Lutein inhibits an enzyme secreted by fat cells called Complement Factor D also called Adipsin. This is an enzyme that limits fat cells from dumping their contents into the bloodstream and involved in the uptake of glucose and converting it to fat.  Lutein in one study has been shown to reduce the enzyme about half as measured at fat cells in culture.  So, by reducing the enzyme adipsin, fat cells have a hard time growing and also want to let go of their fatty contents which helps them to shrink.
A Little Extra
Lutein is implicated in cancer reduction of the prostate and breast. The research on cancer of the breast suggests that lutein increases free radical counts in cancer cells but protects healthy cells.  Free radicals increase oxidation rates and excessive oxidation creates damage to the cell which will often kill the cell. In another study, lutein was protective against prostate cancer. 
Lutein helps to protect skin cells from photo aging and photocarcinogenesis. In a study with mice, lutein and zeaxanthin protected hairless mice from UVB exposure and reduced skin inflammation.  It is not time to put away your sunscreen, but a little extra protection is a great idea.
Lutein is great for your eyes but also great for your brain. It can possibly help with athletic performance by influencing higher activity levels, building muscle and reducing fat. Lutein also may offer protection against heart disease, certain types of cancer, and sun damage to your skin.
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