Lutein best bet for macular degeneration

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Lutein best bet for macular degeneration

 

http://www.knowledgeofhealth.com/report.asp?story=Lutein%20best%20bet%20for%20ma\

cular%20degeneration & catagory=Eyes

 

The Drug & Therapeutics Bulletin in once-Great Britain took a pot-shot at

lutein dietary supplements this past week, suggesting they are unproven, and

advising senior adults to avoid wasting their money. Well, this writer, piqued

by

health authorities once again misleading the public, decided to challenge them

head on. Here’s the email that was sent to the editor of the Drug and

Therapeutics Bulletin.

 

February 10, 2006

 

Dr. Ike Iheanacho, editor

Drug & Therapeutics Bulletin

London

 

Bill Sardi, Knowledge of Health, Inc., author of User's Guide to Eye

Health Supplements (Basic Health Publications, Inc., 2003)

 

Your desire to protect the public from unfounded health claims made by some

dietary supplement manufacturers requires judicious consideration of

surrounding facts.

 

You have expressed “concern about ‘promotional claims for some nutritional

supplements’ aimed at people worried about macular degeneration,†that

certain

claims “appear to be medicinal†and would therefore “be in breach of UK

medicines legislation.†From a legal standpoint, this is true, but from a

scientific standpoint, current law may stand in the way of adequately serving

the

public.

 

While no lutein supplement maker can make a claim their products prevent

macular degeneration, that doesn’t mean there isn’t a large body of

scientific

evidence to the contrary. Supplement manufacturers must await long-term

interventional studies before they can make health claims for their products,

but that

certainly doesn’t mean the public will not benefit from taking supplemental

lutein. Most older adults facing the risk for insidious loss of central vision

due to macular degeneration haven’t the remaining years of life to wait for

such long-term studies. They must make decisions based upon the best available

evidence currently at hand. The public is not foolish or unwise in taking

lutein supplements.

 

Your article suggests that formulas which provide “a specific combination of

antioxidant vitamins and zinc (AREDS formula)†can only be recommended to

specific groups of patients with macular degeneration with advanced disease in

one

eye only. The AREDS formula only addresses the rate of progression, not the

prevention, of this debilitating eye disease. Millions of at risk individuals

have been offered nothing in regards to prevention.

 

The AREDS study and dietary supplement formula were conceived years ago and

did not include lutein. Your DTB bulletin suggests a diet rich in green

vegetables, which provide lutein in variable and small amounts, which is

somewhat of

a concession that lutein may be of value. However, you regard lutein

supplements to be of unproven (but certainly not disproven) value.

 

More than 25 years ago researchers withdrew lutein (also called xanthophylls)

from the diet of monkeys and the monkey eyes rapidly exhibited changes in the

retina typical of macular degeneration. (1)

 

It should be noted that great apes that consume from in the wild have

adequate levels of retinal lutein, while laboratory monkeys on diets that are

similar

to those consumed by many humans eating processed and pre-prepared foods,

exhibit low retinal and circulating levels of lutein. (4)

 

Dietary studies find the combined intake of foods containing lutein and

zeaxanthin as the nutritional factor most strongly related to reduced risk for

age-related macular degeneration. The consumption of 6 milligrams of lutein per

day conferred reduced risk for this sight-threatening eye disease. (2) An intake

of this amount of lutein from dietary sources requires near every-day

consumption of foods like spinach and kale, which some adults cannot consume due

to

oxalate content related to kidney stones.

 

Surely, scientific studies have conclusively shown that dietary shortages of

lutein can result in abnormalities in the back of the eyes. Studies clearly

show monkeys on normal and supplemented diets exhibit macular pigment

(xanthophylls-lutein) while lutein is absent in the retina of animals placed on

a

purified diet. (3)

 

Low retinal levels of lutein correlate with macular degeneration. (4)

Lutein supplementation has been shown to increase measurable retinal action

potential produced by light stimulation. (5)

It should also be said that the rise in cases of macular degeneration has not

only come with increased longevity, but also with the increase in obesity

which plagues well-fed western populations. Greater body fat increases storage

of

lutein in fatty tissues and may deprive the retina of lutein. (6)

Supplementation may be the only way to provide sufficient amounts of lutein for

adequate

delivery to the retina.

 

Lutein is a filter for toxic ultraviolet and blue-light in the center of the

retina (macula). Lutein may reduce blue light intensity by 40-90%. (7)

Although the evidence regarding lutein and macular degeneration is still

associative

in nature, “it is biologically plausible.†(8)

The importance of lutein for ocular health has now been raised by researchers

who consider lutein a conditionally essential nutrient. (9)

Your bulletin should have been addressed privately to supplement makers, not

issued to scare at-risk individuals away from safe supplements, which was its

likely intent. Lutein supplements are the only reliable and measured source of

lutein available to prevent macular degeneration, and due to the problem

posed by oxalates, are safer and likely more effective than food.

 

References

 

(1) MR Malinow, L Feeney-Burns, LH Peterson, ML Klein and M Neuringer,

Diet-related macular anomalies in monkeys, Investigative Ophthalmology & Visual

Science, 19: 857-863, 1980.

 

(2) Seddon JM, et al, Dietary carotenoids, vitamins A, C, and E, and advanced

age-related macular degeneration. Eye Disease Case-Control Study Group,

Journal American Medical Assn 272:1413-20, 1994.

 

(3) Martha Neuringer,Marita M. Sandstrom, Elizabeth J. Johnson, and D. Max

Snodderly, Nutritional Manipulation of Primate Retinas, I: Effects of Lutein or

Zeaxanthin Supplements on Serum and Macular Pigment in Xanthophyll-Free Rhesus

Monkeys, Investigative Ophthalmology and Visual Science. 45:3234-3243, 2004.

 

(4) Bone RA, Landrum JT, Mayne ST, Gomez CM, Tibor SE, Twaroska EE.Macular

pigment in donor eyes with and without AMD: a case-control study.Investigative

Ophthalmology 42: 235-40, 2001.

 

(5) Falsini B, Piccardi M, Iarossi G, Fadda A, Merendino E, Valentini P.,

Influence of short-term antioxidant supplementation on macular function in

age-related maculopathy: a pilot study including electrophysiologic assessment.

Ophthalmology 110:51-60, 2003]

 

(6) Broekmans WM, Berendschot TT, Klopping-Ketelaars IA, de Vries AJ,

Goldbohm RA, Tijburg LB, Kardinaal AF, van Poppel G., Macular pigment density in

relation to serum and adipose tissue concentrations of lutein and serum

concentrations of zeaxanthin. American Journal Clinical Nutrition 76: 595-603,

2002;

Hammond BR Jr, Ciulla TA, Snodderly DM., Macular pigment density is reduced in

obese subjects. Investigative Ophthalmology Visual Science 43: 47-50, 2002.

 

(7) Krinsky NI, Landrum JT, Bone RA. Biologic mechanisms of the protective

role of lutein and zeaxanthin in the eye. Annual Review Nutrition 23:171-201,

2003.

 

Krinsky NI, Possible biologic mechanisms for a protective role of

xanthophylls. Journal Nutrition 132: 540-42S, 2002.

 

(9) Semba RD, Dagnelie G, Are lutein and zeaxanthin conditionally essential

nutrients for eye health? Medical Hypotheses 61:465-72, 2003.