♦ Lutein and zeaxanthin are major supplements for eye health

Lutein and Zeaxanthin have become of major interest as a nutritional supplements because they are essential components of the retina, especially the macula. It does need to be borne from the outset that EFSA would not support an Article 13 claim for lutein in maintaining ‘normal vision’ because of a lack of evidence from human intervention studies.

Lutein is a carotenoid isolated from marigolds (Tagetes erecta) in particular for supplement use. Along with zeaxanthin, it has a five-fold higher concentration in the macula compared with the retina (Handelman et al., 1988) and is also found in the lens, retina, breast and cervix tissue, brain and skin (Stahl and Sies, 2005). Generally, it is free lutein rather than the esterified form which is found in tissues. The ester group must be removed for bioavailability.

Maize or corn has the highest quantity of lutein (60%) of all vegetables whilst egg yolk contains the highest mole percentage (over 85%). A review of the USDA database shows that both lutein and zeaxanthin are present too in Romaine lettuce which contains 2.3 mg/100g, kale has 40 mg/100g and spinach has 12 mg/100 g (USDA, 2003).

It is well established that lutein and zeathanthin protect the macular in the eye from oxidative damage and absorb damaging UV and blue light, and according to epidemiological studies believed to not only reduce the effect of macular degeneration, but reduce cataract formation. There are many comprehensive reviews covering the mechanisms of protection (Krinsky et al., 2003). Antioxidants are quenchers of singlet oxygen, the triplet state of many photosensitisers and it inhibits lipid peroxidation.

Lutein And Cataract Formation

One distressing eye condition is the formation of cataracts which is the gradual development of opacity in the lens. Lutein is found in the lens and by about 3 to 8 fold higher than other carotenoids (Gale et al., 2001). An intake of 6 mg/day of lutein by both sexes in a study, reduced the odds of cataract extraction by nearly 20% (Brown et al., 1999; Chasan-Taber et al., 1999). A good nutritional diet which includes lutein is supposed to maintain a healthy lens and reduce cataracts. It could also aid visual acuity and reduce glare sensitivity in those suffering age-related cataracts (Olmedilla et al., 2003).

Age-related macular degeneration (AMD) has a number of associated risk factors such as age, smoking, being female, having a pale iris colour, sun exposure and generally a poor nutritional status. Taking 6mg of lutein or zeaxanthin daily is claimed to have reduced the odds of developing AMD by nearly 60% in an early study (Seddon et al., 1994). LAST, a lutein antioxidant Supplementation Trial also demonstrated a benefit in eye health (Richer et al., 2004). This was a 12 month randomised, placebo controlled and double-blind intervention study which had 3 arms using 10 mg FloraGLO (Kemin Ind.)) lutein, 10 mg FloraGLO lutein and other nutrients versus a control. The subjects were 90 male veterans. The researchers observed a number of improvements with lutein supplementation alone in visual health such as better acuity, faster glare recovery and an increase of between 36 to 42% in the MPOD (macular pigment optical density).

There is a growing body of evidence to try and support lutein supplementation to 6 mg/day in normal eye health but there is insufficient evidence at the moment. The legal scene is complex and EFSA have stated that the ADI is 1 mg lutein/kg body weight/day which is now extended to lutein with high concentrations of total carotenoids extracted from Tagetes erecta and at ester levels of at least 60%. EFSA has concluded that there was not enough evidence to establish a cause and effect relationship between consumption of lutein or a combination with zeaxanthin and the maintenance of normal vision (EFSA, 2010, 2011). There have been resubmissions to obtain a claim under Article 13.5.

I’d recommend Sundown Naturals’ Lutein Gummies which provides 12 mg of  FloraGlo® lutein per serving in a fruit punch flavoured offering.

References

Brown, L., Rimm, E.B., Seddon, J.M., Giovannucci, E.L., Chasan-Taber, L., et al. (1999) A prospective study of carotenoid intake and risk of cataract extraction in US men. Am. J. Clin. Nutr. 70 pp. 517–24
Chasan-Taber, L.,Willett, W.C., Seddon, J.M., Stampfer, M.J., Rosner, B., et al. (1999) A prospective study of carotenoid and vitamin A intakes and risk of cataract extraction in US women. Am. J. Clin. Nutr. 70 pp. 509–16
EFSA (2010) Scientific Opinion on the substantiation of health claims related to lutein and maintenance of vision (ID 1603, 1604, 1931) pursuant to Article 13(1) of Regulation (EC) No 1924/2006. EFSA Journal 8(2) pp. 1492 [19 pp.]. doi:10.2903/j.efsa.2010.1492
EFSA (2011) Scientific Opinion on the substantiation of a health claim related to lutein in combination with zeaxanthin, and maintenance of normal vision (ID 1606) pursuant to Article 13(1) of Regulation (EC) No 1924/2006. EFSA Journal 9(4) pp. 2039 [14 pp.]. doi:10.2903/j.efsa.2011.2039
Gale CR, Hall NF, Phillips DI, Martyn CN. 2001. Plasma antioxidant vitamins and carotenoids and age-related cataract. Ophthalmology 108   pp. 1992–98
Handelman, G.J., Dratz, E.A., Reay, C.C., et al. (1988) Carotenoids in the human macula and whole retina. Invest . Ophthalmol Vis. Sci. 29 pp. 850–5
Krinsky NI, Landrum JT, Bone R,A. (2003) Biologic mechanisms of the protective role of lutein and zeaxanthin in the eye. Annual Review of Nutrition 23, pp. 171–201.
Olmedilla B, Granado F, Blanco I & Vaquero M (2003) Lutein, but not a-tocopherol, supplementation improves visual function in patients with age-related cataracts: A 2-y double blind, placebo-controlled study. Nutrition 19, pp. 21–25.
Richter S, Stiles W, Statkute L, Pulido J, Frankowski J, Rudy D, Pei K, Tsipursky M, Nyland J: (2004) Double-masked, placebo-controlled, randomized trial of lutein and antioxidant supplementation in the intervention of atrophic age-related macular degeneration: the Veterans LAST study (Lutein Antioxidant Supplementation Trial). Optometry 75 pp. 216– 230
Seddon JM, Ajani UA, Sperduto RD, Hiller R, Blair N, Burton TC, Farber MD, Gragoudas ES, Haller J, Miller DT, et al.(1994) Dietary carotenoids, vitamin A, C, and E, and advanced age-related macular degeneration. Eye Disease Case-Control Study Group. JAMA. 272 pp. 1413–1420
Stahl, W.; Sies, H. (2005) Bioactivity and protective effects of natural carotenoids. Biochim. Biophys. Acta. 1740, pp. 101-107.
USDA (2003) USDA National Nutrient database for Standard reference, Release 16. Nutrient Data laboratory Home Page, http://www.nal.usda.gov/fnic/foodcomp