Q&A: What foods or supplements maximize absorption (ie, blood levels) of zeaxanthin or lutein?
Question: A very knowledgeable reader asked the following:
If we assume for now that the best natural or nutritional supplements are zeaxanthin or lutein, what foods or supplements maximize absorption (ie, blood levels)? The reason I am asking this is that I read somewhere that corn has very high zeaxanthin levels, but the bioavailability is low for some reason. If this is so, one may have the same problem with orange peppers, etc, or even with certain nutritional supplements. Also with nutritional supplements it is very hard to know what is actually in them and how effectively the actual formulation is absorbed.
Perhaps all that one needs to do is take some fatty food like cold water fish at the same time to increase absorption of a lipid soluble compound...
I am also wondering whether antioxidants in the macula are very different from other antioxidants, given that they have to work effectively at unusually low PO2 levels.
Answer: These are hard questions. It is clear that oral ingestion of lutein and zeaxanthin increase the serum level and increase the pigment levels in the macula in most but not all people. Recent evidence showed that supplementation with lutein increases the macular pigment more than with zeaxanthin. There is competition in the gut for absorption between lutein and zeaxanthin and most nutritional tables don’t separate them but list them together. Corn has very high levels of zeaxanthin which may make the bioavailability of the lutein less. High doses of fiber in corn may also decrease the bioavailability. As the reader suggested, the concomitant intake of fat seems to increase the absorption of both.
We should be suspicious of nutritional supplements because no one is monitoring them. The FDA is too busy making sure pharmaceutical drugs are safe. Whenever possible, I think it’s better to get the nutrients from colorful fruits and vegetables than from supplements. I would trust your diet more than supplements.
I know that a lot of people are tempted to do both, in otherwords eat a diet rich in these nutrients and then take megadoses of supplements. I would be careful about overdoing it because there is often competitive inhibition between various nutrients. For instance, too much zinc can make you anemic by inhibiting copper metabolism.
We think that vitamins C, E, and beta-carotene work in the macula as they do elsewhere in the body. We know from epidemiological studies that diets high in these vitamins are associated with a lower risk of AMD. We also know from the AREDS trial, that supplementation reduces the rate of progression to severe AMD and also visual loss.
I hope this helps.
If we assume for now that the best natural or nutritional supplements are zeaxanthin or lutein, what foods or supplements maximize absorption (ie, blood levels)? The reason I am asking this is that I read somewhere that corn has very high zeaxanthin levels, but the bioavailability is low for some reason. If this is so, one may have the same problem with orange peppers, etc, or even with certain nutritional supplements. Also with nutritional supplements it is very hard to know what is actually in them and how effectively the actual formulation is absorbed.
Perhaps all that one needs to do is take some fatty food like cold water fish at the same time to increase absorption of a lipid soluble compound...
I am also wondering whether antioxidants in the macula are very different from other antioxidants, given that they have to work effectively at unusually low PO2 levels.
Answer: These are hard questions. It is clear that oral ingestion of lutein and zeaxanthin increase the serum level and increase the pigment levels in the macula in most but not all people. Recent evidence showed that supplementation with lutein increases the macular pigment more than with zeaxanthin. There is competition in the gut for absorption between lutein and zeaxanthin and most nutritional tables don’t separate them but list them together. Corn has very high levels of zeaxanthin which may make the bioavailability of the lutein less. High doses of fiber in corn may also decrease the bioavailability. As the reader suggested, the concomitant intake of fat seems to increase the absorption of both.
We should be suspicious of nutritional supplements because no one is monitoring them. The FDA is too busy making sure pharmaceutical drugs are safe. Whenever possible, I think it’s better to get the nutrients from colorful fruits and vegetables than from supplements. I would trust your diet more than supplements.
I know that a lot of people are tempted to do both, in otherwords eat a diet rich in these nutrients and then take megadoses of supplements. I would be careful about overdoing it because there is often competitive inhibition between various nutrients. For instance, too much zinc can make you anemic by inhibiting copper metabolism.
We think that vitamins C, E, and beta-carotene work in the macula as they do elsewhere in the body. We know from epidemiological studies that diets high in these vitamins are associated with a lower risk of AMD. We also know from the AREDS trial, that supplementation reduces the rate of progression to severe AMD and also visual loss.
I hope this helps.
If you have a question or topic for me to discuss, then please send me an e-mail.
posted by James C. Folk, M.D. at 3:46 PM
2 Comments:
Research is confirming that macular degeneration can be very responsive to nutritional supplementation. A large research study from Harvard showed that even supplementing with 6 mg of lutein per day could reduce your likelihood of getting macular degeneration by 57% (Seddon, J.M., U.A. Ajani, et al. (1994). “Dietary carotenoid, vitamins A, C, E, and advanced age-related macular degeneration. Eye Disease Case-Control Study Group Jama 272(18):1413-20). That same study showed that the specific carotenoids, lutein and zeaxanthin, which are primarily obtained from dark green leafy vegetables, were most strongly associated with a reduced risk for AMD. Individuals consuming the highest levels of carotenoids had a statistically significant 43% lower risk for AMD.
So there certainly are preventative measures you can take. Additional beneficial nutrients include omega-3 fatty acids, taurine, vitamins A and E, selenium, zinc copper, beta-carotene, gingko biloba.
Regarding having macular degeneration, research has shown that this is a condition that can be very responsive to specific nutritional supplementation (lutein, zeaxanthin, taurine, omega-3 fatty acids, vitamins A and E, selenium, beta-cartoene, zinc and copper to name a few), diet and lifestyle. Also, microcurrent stimulation done daily at home along with specific supplementation can be very effective in helping protect against vision loss. The last research study done by a Dr. Ed Paul showed that 73% of the people who did microcurrent stimulation daily along with specific supplementation showed improved vision up to 2-3 lines on the eye chart. As a result of this study, there are now 4 double blind FDA approved studies starting (including one at New York Eye & Ear Infirmiary) studying the benefits of the microcurrent stimulation for macular degeneration along with some other retinal dystrophies. For more information and related research studies, you can go to http://www.naturaleyecare.com/diseases.asp?d_num=8 -- you can also read the specific research studies on microcurrent stimulation and macular degeneration at http://www.naturaleyecare.com/store/detail.aspx?ID=1545
For questions and answers, you can also go to our blog on natural eye care at http://www.bulletinboards.com/message.cfm?comcode=nec2
I need to respond to the comment posted by Michael because it is misleading. Dr. Seddon’s research group gave questionnaires to their subject and then divided their responses into quintiles (fifths). The subjects in the highest quintile (top 20%) of a diet rich in carotenoids had a 43% lower risk of AMD compared to the subjects in the lowest quintile (bottom 20%). The article said nothing about reducing AMD by supplementing the diet with 6mg of lutein per day.
We don’t know if lutein supplementation helps and that is why AREDS II (see Nov 9th blog) is testing lutein/zeaxanthin supplementation along with omega-3 long-chain polyunsaturated fatty acids. I would recommend for now that you eat lots of dark green and brightly colored vegetables. There is no evidence that taurine, selenium, or ginkgo biloba helps AMD.
There is no scientific basis for why microstimulation would be helpful in AMD. My patients who have tried it had no improvement. I looked on the naturaleyecare website and it listed studies that “proved” that microstimulation was helpful but apparently none of these were ever published. Remember you pretty much can say anything on the web.
One of the main purposes of this blog is to protect patients from unsubstantiated claims made by people who want to sell you something. Caveat emptor! That translates to “Let the buyer beware.” Apparently such activities and practices have been going on for years.
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