What's a Carotenoid?

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A carotenoid is a natural chemical compound found mostly in plant pigments, including many colorful plants we eat every day. Actually, there isn't just one carotenoid, there are more than 500 plant carotenoids in total. The carotenoids provide red, orange or yellow colors to plants, and some of those carotenoids may have health benefits for us when we eat them.

Some animal-based foods contain carotenoids, too, such as mollusks, crustaceans, and fish.

These marine animals don't produce carotenoids themselves, but they either feed heavily on plants that contain algae or they eat other sea creatures that have eaten a lot of carotenoids. Egg yolks also contain significant amounts of carotenoids, especially when hens are given carotenoid-rich feed.

Probably the best-known carotenoid is beta-carotene, the primary source of vitamin A from plants. But there are a few more carotenoids that have been found to have potential health benefits, including lycopene, lutein, zeaxanthin, cryptoxanthin, alpha-carotene and astaxanthin. They all work as antioxidants, and they just happen to be found in very nutritious foods.

Beta-Carotene

Beta-carotene is a pigment found in large amounts in orange and yellow fruits and veggies. When you eat these fruits and vegetables, your body converts beta-carotene to vitamin A, which is essential for a strong immune system, normal vision, and healthy skin.

So, beta-carotene is known as a provitamin A carotenoid.

Beta-carotene is an antioxidant, which means it can help protect your body's cells from free radical damage that comes from things like pollution, sun exposure, and smoking. It's also available as a dietary supplement, but it's not clear if taking beta-carotene supplements is a good thing.

Taking too much beta-carotene has been linked to an increased risk of lung cancer in smokers. On the other hand, beta-carotene supplements may help to slow the progression of age-related macular degeneration, when taken as part of a particular antioxidant formula (more on that later).

Lycopene

Lycopene is a reddish pigment found primarily in tomatoes, but also apricots, watermelons, and pink grapefruit. Some earlier research studies have associated a higher lycopene intake with a lower risk of prostate cancer, but it hasn't been seen in later studies, so it's not clear if the risk reduction in the earlier studies was due to lycopene or something else. Lycopene is also available in supplemental form, but there isn't much evidence for benefit.

Lutein

Lutein is another yellow to orange carotenoid found in dark green leafy vegetables like spinach and kale, yellow corn, egg yolks, squash, and carrots. Lutein is concentrated in the retinas of your eyes, so it's thought to be beneficial for vision.

Lutein is also one of the antioxidants that appear to be useful as a supplement. A study called the Age-Related Eye Disease study used Twin Lab's Ocuvite and showed that a combination of zinc, vitamins C and E, beta-carotene, copper, and lutein could help slow down the progression of macular degeneration.

Zeaxanthin

Zeaxanthin is typically grouped in with lutein, probably because it's also concentrated in the retina of your eye. It's also found in the same foods, with the highest levels being in orange foods. Egg yolks, orange peppers, orange juice, and mango are all high in zeaxanthin.

Cryptoxanthin and Alpha Carotene

Cryptoxanthin is also found in orange and yellow fruits and veggies. But it's somewhat like beta-carotene in that it can be converted to vitamin A if necessary. 

Alpha-carotene is also a provitamin A carotenoid, but it takes about twice as much alpha-carotene (or cryptoxanthin) compared to beta-carotene to make the same amount of vitamin A. Alpha-carotene may potentially have health benefits, but currently research hasn't shown anything definite beyond its ability to be converted to vitamin And it's ability to be converted to vitamin A.

Astaxanthin

Astaxanthin is a salmon-colored carotenoid that found in salmon, trout, shrimp, and some types of algae. It may have strong antioxidant and anti-inflammatory potential, but research is still in the early stages so it's not clear if taking astaxanthin supplements will do anything at all. So it's best to get your astaxanthin from foods. Salmon is the best source because it's high in both astaxanthin and omega-3 fatty acids.

Increase Your Intake of Carotenoids

The best way to get more carotenoids into your diet is to increase your intake of fruits and vegetables. Since the carotenoids are all fat-soluble, you can improve the absorption of carotenoids by adding a bit of healthy fat to your meal. Here are some ideas:

  • Make a large green salad with lots of sliced carrots and tomatoes top with a drizzle of olive oil and vinegar.
  • Saute your spinach or kale in olive oil and serve with chopped nuts.
  • Make a fruit smoothie with blueberries, kale, a banana and some avocado.
  • Dip sliced carrots into hummus for a healthy snack.
  • Serve salmon in place of red meat once or twice each week.
  • Bake sweet potatoes and top them with a little butter, salt, and pepper.

Cooking and processing foods can increase the concentration of carotenoids. For example, tomatoes are high in lycopene, but you'll get much more lycopene if you consume tomato paste, soup or juice. 

Please note that most of these carotenoids are available as over-the-counter dietary supplements. They're generally considered safe to be safe, but speak to your doctor before taking any of these carotenoids as supplements, especially if you have any health conditions. And please read the label directions unless your health care provider has given you different instructions.

Sources:

Hussein G, Sankawa U, Goto H, Matsumoto K, Watanabe H. "Astaxanthin, a carotenoid with potential in human health and nutrition." J Nat Prod. 2006 Mar;69(3):443-9. 

Maoka, T. "Carotenoids in marine animals." Mar Drugs. 2011; 9(2): 278–293. 

Micronutrient Information Center. "Carotenoids." http://lpi.oregonstate.edu/mic/dietary-factors/phytochemicals/carotenoids. 

University of Maryland Medical Center. "Beta-carotene." http://umm.edu/health/medical/altmed/supplement/betacarotene. Updated 3/23/2015. 

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