Introduction
Lutein and Zeaxanthin – these two carotenoids are found in high levels in dark-green leafy vegetables and are known to concentrate in the macula of the eye. They have been shown to play a role in the prevention and treatment of macular degeneration and, more recently, retinitis pigmentosa.
Macular Degeneration and the Role of Lutein and Zeazanthin:
The macula, especially the central portion (the fovea), within the retina of the eye, owes its yellow colour to its high concentration of Lutein and zeazanthin. These yellow carotenes, although not a source of Vitamin A, function as an antioxidant, prevent oxidative damage to the area of the retina responsible for fine vision and play a role in the prevention of macular degeneration - the leading cause of severe visual loss in North America and Europe, in persons aged fifty-five years and older.1
There is strong evidence that Lutein and zeazanthin reduce the risk (up to 57%) of age-related macular degeneration and may help to stabilize this condition.2 Lutein may also help to prevent cataracts.3
Some authorities recommend an antioxidant combination of supplements to help treat macular degeneration. Generally, 5 mg of Lutein plus 50,000 I.U. of mixed carotenoids are included in this protocol.4 Lutein supplementation studies have shown that macular pigment increases by an average of 5.3% after 4 weeks of supplementation with 10 mg of Lutein.5 Zeazanthin supplementation is typically included at 1 mg per day, but it should be noted that Lutein can be converted to zeazanthin in the retina.
Other studies using Lutein supplementation have also revealed significant increases in macular pigment.6
A study of 13 patients with retinitis pigmentosa and 3 patients with macular degeneration, demonstrated significant improvement when subjects were given 40 mg of Lutein supplementation for 9 weeks, followed by 20 mg/day thereafter. The trial lasted 26 weeks in total. The findings of this study showed that patients with retinitis pigmentosa experienced significant improvement in both their visual acuity and visual field area within the first four weeks of Lutein supplementation. Blue-eyed subjects reported more dramatic results, in terms of visual acuity from Lutein supplementation than did dark-eyed individuals. Individuals also taking Vitamin A and/or Beta-carotene benefited more than others in terms of visual acuity improvements. Dark-eyed individuals do not appear to increase their macular pigment from supplements as much as blue-eyed people, according to this and previous studies, which may imply that these individuals have a lesser need for this nutrient than do blue-eyed individuals, in order to protect the macular region of the eye from damage induced by blue light.7
In the same study, the 3 patients with macular degeneration, also demonstrated significant improvement upon ingesting 40 mg of Lutein supplementation for 9 weeks, followed by 20 mg/day thereafter. The trial lasted 26 weeks in total.7
A large number of experimental investigations demonstrate that age-related macular degeneration is caused by, or in some way promoted by, free radical damage from sunlight (uv-light, especially blue light) and cigarette smoking. Higher dietary and supplemental intake of Lutein and zeazanthin have been shown to result in increased concentrations of these nutrients in the macula, where they absorb damaging blue light, helping to intercept and neutralize free radical damage, and reduce the risk of macular degeneration.8-13 For example, in a 140 day study involving two individuals, who consumed 30 mg of free Lutein per day, macular pigment optical density increased 39% in one subject and 21% in the other subject. This change in macular pigment optical density was estimated to reduce the amount of damaging blue light reaching the photoreceptors, Bruch’s membrane, and the retinal epithelium (the vulnerable tissues affected by age-related macular degeneration), by 30 to 40%.6
Dosage
The average intake of Lutein from food each day ranges from 0.6 to 0.8 mg, but half a cup of cooked spinach, kale, or broccoli adds from 1.2 to 10 mg of Lutein to the diet.24
Many health experts recommend about 6 mg of Lutein per day as part of a supplementation program for the management of various eye conditions (e.g., macular degeneration, cataracts, retinits pigmentosa).25,26 However, studies using 20 and 40 mg of Lutein supplementation have demonstrated impressive results in these cases without producing any apparent adverse side effects over a five to six-month period.6,7
Adverse Side Effects and Toxicity
No reports of toxicity have been reported to date with Lutein or Zeazanthin supplementation at the above noted levels.6,7,14
Drug-Nutrient Interactions
The following drugs are reported to decrease the absorption Lutein and, thus should not be ingested at the same time.
Orlistat15,16,17
Mineral oil18
Bile Acid Sequestrants19,20
Olestra - containing products21,22
Chitosan23
1. Landrum JT, Bone RA, Kilburn MD. The macular pigment: a possible role in protection from age-related macular degeneration. Adv Pharmacol 1997;38:537-56.
Seddon JM, Ajani UA, Sperdato RD. Dietary carotenoids, Vitamin A, C, and E, and advanced age-related macular degeneration. JAMA 1994;272:1413-20.
Hankinson SE, Stampfer MJ, Seddon JM, Colditz GA Rosner B, Speizer FE, et al. Nutrient intake and cataract extraction in women: a prospective study. Br Med J 1992;305:335-9.
Murray M, Pizzorno J. Encyclopedia of Natural Medicine. 2nd edition. Rocklin, CA: Prima Publishing; 1998.
Berendschot TT, Goldbohm RA Klopping WA, van de Kraats J, van Norel J, van Norren D. Influence of Lutein supplementation on macular pigment, assessed with two objective techniques. Invest Ophthalmol Vis Sci 2000;41(11):3322-6.
Landrum JT, Bone RA, Joa H, Kilburn MD, Moore LL, Sprague KE. A one year study of the macular pigment: the effect of 140 days Lutein supplement. Exp Eye Res 1997;65(1):59-62.
Dagnelie G, Zorge IS, McDonald TM. Lutein improves visual function in some patients with retinal degeneration: a pilot study via the Internet. Optometry 2000;71(30):147-64.
Khachik F, Bernstein PS, Garland DL. Identifaction of lutein and zeazanthin oxidation products in human and monkey retinas. Invest Ophthalmol Vis Sci 1997;38(9):1802-11.
Sommerburg O, Keunen JE, Bird AC, Van Kuijk FJ. Fruits and vegetables that are a source of lutein and zeazanthin: the macular pigment in human eyes. Br J Ophthalmol 1998;82(8):907-10.
Sommerburg OG, Siems WG, Hurst JS, Lewis JW, Kliger DS, van Kuijk FJ. Lutein and zeazanthin are associated with photoreceptors in the human retina. Curr Eye Res 1999;19(6):491-5.
Rapp LM, Maple SS, Choi JH. Lutein and zeazanthin concentrations in rod outer segment membranes from perifoveal and peripheral human retina. Invest Ophthalmol Vis Sci 2000;41(5):1200-9.
Johnson EJ, Hammond BR, Yeum KJ, Qin J, Wang XD, Castaneda C, et al. Relation among serum and tissue concentrations of lutein and zeazanthin and macular pigment density. Am J Clin Nutr 2000;71(6):1555-62.
Bone RA Landrum JT, Dixon Z, Chen Y, Llerena CM. Lutein and zeazanthin in the eyes, serum and diet of human subjects. Exp Eye Res 2000;71(3):239-45.
Hathcock JN. Evaluation of Vitamin A toxicity. Am J Clin Nutr 1990;52:183-202.
Heck AM, Yanovski JA Calis KA Orlistat, a new lipase inhibitor for the management of obesity. Pharmacotherapy 2000;20(3):270-9.
Xenical (orlistat), product prescribing information. Nutley, NJ: Roche laboratories, Inc.; 2000. Finer N, James WP Kopelman PG, Lean ME, Williams G. One year treatment of obesity: a randomized, double-blind, placebo-controlled, multicentre study of orlistat, a gastrointestinal lipase inhibitor. Int J Obes Relat Metab Disord 2000;24(3):306-13.
Diarrhea and Constipation. In: Berdow R, Fletcher AJ, Beers MH et al, editors. The Merck manual of diagnosis and therapy. 16th ed. Rahway, NJ: Merck research laboratories; 1992. p. 810.
Schwarz KB, Goldstein PD, Witztum JL, Schonfeld G. Fat-soluble vitamin concentrations in hypercholesterolemic children treated with colestipol. Pediatrics 1980;65(2):243-50.
Knodel LC, Talbert RL. Adverse effects of hypolipidaemic drugs. Med Toxicol 1987;2(1)10-32.
Koonsvitsky BP, Berry DA, Jones MB, Lin PY, Cooper DA, Jones DY, et al. Olestra affects serum concentrations of alpha-tocopherol and carotenoids but not Vitamin D or Vitamin K status in free-living subjects. J Nutr 1997;127(8 Suppl):1636S-1645S.
Thomson AB, Hunt RH, Zorich NL. Review Article: Olestra and its gastrointestinal safety. Aliment pharmacol Ther 1998;12(12):1185-200.
Deuchi K, Kanauchi O, Shizukuishi M, Kobayashi E. Continuous and massive intake of chitosan affects mineral and fat- soluble vitamin status in rats fed on a high-fat diet. Biosci Biotechnol Biochem 1995;59(7):1211-6.
Webb D. Can lutein pills save your precious sight? Supplement News - Prevention 2000;52(11):57, 2, 2c.
Cantrell S, Ausich RL. Exploring the role of antioxidants in preventing ARMD. Optometry Today 1999.)
Pratt S. What we know about ARMD and nutrition. Rev