Update: Age-Related Macular Degeneration (AMD) Research

[Diane Alexander, Ph.D.]

An upcoming issue of Vision Research is highlighting Age-related Macular Degeneration (AMD) research. There is a growing body of evidence suggesting that increased consumption of certain nutrients, specifically lutein and zeaxanthin, augments levels of these molecules in the macula, subsequently improving visual function and reducing the risk for certain age-related eye diseases.

Macular Pigment Optical Density. The ability to measure lutein and zeaxanthin levels in the macula is of great importance to enhance research, to provide a methodology to assess eye health and offer responsive, appropriate clinical care. Traditional laboratory methods used to measure lutein and zeaxanthin, namely high-performance liquid chromatography (HPLC), cannot be used on living eyes, so a surrogate optical indicator of xanthophyll levels in the eye is often employed: macular pigment optical density (MPOD). MPOD is a measurement of the attenuation of blue light by macular pigment and is linearly related to the amount of lutein and zeaxanthin in the macula.

Clinical Support

• Over two dozen studies have been published demonstrating an increase in macular carotenoids following lutein/zeaxanthin supplementation of 2-30 mg per day or a high carotenoid diet^1-26.

• The body of evidence from eight epidemiological studies provides support from an observational perspective that consumption of lutein and zeaxanthin from food is associated with reduced risk for AMD^27-33.

• The anatomical location of macular carotenoids is ideal for them to act as an optical filter. Consistent with this, improvements in visual function and comfort parameters have been associated with lutein and zeaxanthin supplementation and subsequent increases in MPOD in close to a dozen published studies^{34-38,17,39,14,40-43}.

• A growing body of evidence suggests a relationship between levels of macular pigment and risk of age-related eye diseases, although a direct link has not been established. Risk factors for AMD including tobacco use, light iris color, age, obesity, and gender are associated with low levels of MPOD. Additionally, five studies have shown that in eyes that have been afflicted with AMD (examined post-mortem) or eyes that have been deemed to have a higher risk for AMD (due to AMD in the fellow eye) tend to have lower MPOD than healthy eyes or eyes that are deemed to be at lower risk to AMD^44-47,4.

Based up these findings there is considerable interest in incorporating methods to measure the amount of lutein and zeaxanthin in the macula to enhance research and clinical care to identify individuals at risk for visual loss from AMD.

Expert Review of the Value of MPOD Measurement
An article in an upcoming issue of Vision Research reviews the findings from a panel of experts with extensive experience in carotenoid physiology and/or macular pigment measurement⁴⁸. This panel reached a consensus on the value of noninvasive macular pigment measurement as a screening tool for AMD risk based on a review of the literature and their clinical experience. The following conclusions were reached:⁴⁸

• "The current body of knowledge regarding macular lutein and zeaxanthin and their roles in protection against age-related eye diseases support the hypothesis that AMD is in part a manifestation of an ocular deficiency of these molecules and that higher macular levels may protect against AMD."
  
  
• "Macular pigment measurement has the potential to become a commonly tested biomarker to measure risk for eye disease and visual function."

• Approximately, 43% of the U.S. population have what the panel considers to be "low MPOD" -- a central MPOD below 0.2 d.u.⁴⁹

• "More clinical studies are necessary to more accurately define the range of MPOD values and distributions that might correlate with disease risk; however, the body of evidence that supports a link between a lack of macular pigment and AMD risk is growing."

• "Expansion of the scientific data and improvements in methodology and equipment necessary to measure MPOD levels in a diverse population will hopefully bring about a paradigm shift in way we recognize, diagnose, and treat those at risk for AMD and other age-related eye diseases."
  

Macular pigment measurement would enable individuals with low levels of MPOD, and possibly greater risk for eye disease, to take actions to improve their eye health such as increasing their intake of lutein and zeaxanthin through diet and/or supplementation, maintaining a healthy weight, and not smoking. ⁴⁸

Review additional MPOD consensus panel conclusions in Vision Research.




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Diane E. Alexander, Ph.D. is a Technical Service Manger at Kemin Health, LC. She received her Ph.D. in Molecular Microbiology and Microbial Pathogenesis from the Washington University School of Medicine.

[steven newman]

I have been recommending Lutein and Zeaxanthin to my patients for years. They are the only carotenoids that actually protect the ever-so-delicate macula.

Please keep in mind that not all lutein supplements are created equally. I personally recommend Flora-glo lutein, as it is derived from the marigold flower.

Like most things, if it's found in nature, it is better for us than something made in a lab.

[Kent Juffer]

Is this an ad for Flora-Glo lutein or cross-marketing for the MPOD devices on the market?

[Diane Alexander, Ph.D.]

Kemin Health is a science-based company - our goal is to present the entire body of scientific research regarding lutein and eye health to professionals in the eye care industry. We understand there is confusion in the marketplace regarding ocular supplements, and we want to educate doctors about the lutein quality differences in supplements and that all lutein is not created equal and easily absorbed by the body. Kemin Health was the first company to commercialize lutein over 15 years ago, and we have made it our mission to educate doctors and consumers about the benefits of lutein for eye health.

Kemin Health has partnered with leading eye care associations to make resources available for doctors to make it easier to start conversations about ocular nutrition with your patients. Included in this initiative is a CE program that we sponsor called: Reducing the Risk of Age-Related Vision Loss: Macular Pigment and Healthy Vision.

ODwire.org is just one of the many ocular nutrition education initiatives of Kemin Health. We are presenting the science about macular pigment optical density (MPOD) because it is a new, emerging technology in the industry. Additionally, there are a large number of ongoing clinical trials that are evaluating the impact of lutein/zeaxanthin supplementation upon MPOD, and it likely the results of these studies are going to be at the forefront of research presented at scientific meetings. We are not cross-promoting for any particular MPOD device. There are multiple methods to test MPOD and each have their our advantages and disadvantages.

[Kent Juffer]

Diane -

I apologize for my comment. I think I'm becoming a cynical old man.

In my mind, Flora-Glo Lutein from Kemin is the GOLD STANDARD in lutein supplements. I wish the good folks at Kemin would market their own, branded lutein/zeaxanthin supplement. When I make a recommendation for a stand-alone lutein supplement, I have no idea of the quality/bioavailability of the product the patient is purchasing at the pharmacy/big-box store.

I know that Flora-Glo lutein is in the Preservision/AREDS products from Bausch & Lomb. What other companies are using your product?

[Diane Alexander, Ph.D.]

Kent,

No worries We have considered manufacturing our own supplements, but that is not our expertise.

There is a list of other companies that include FloraGLO Lutein in their supplements. You can click on the link below, which will take you to a brochure we have developed listing all the supplements that contain 6 mg or more of FloraGLO Lutein. If you would like brochures for your practice, just send me an email (diane.alexander@kemin.com) and we will send you some free of charge

http://www.floraglolutein.com/KHMKTC...c_Brochure.pdf

Thanks your support of the brand.

Diane

[John L Henahan]

I give out this brochure DAILY. (I have no financial interests). I have found that handing something to the patient after showing them there digital fundus photos and explaining the importance of lutein is very helpful. I then show them that many brands are available. For that, the brochure helps them "connect the dots" and then actually follow through with a purchase. (We do not sell lutein in office at this time).

Kudos to the company for providing these brochures to proactive eye docs who want to help their patients reduce their risk AMD.

[Jeffrey Anshel]

Kent,

I use Macula Complete from Biosyntrx. They use Kemin's product and include ALL the nutrient co-factors that support a healthy retina. This is unlike some "focused" products that just offer a few ingredients.

They also support the Ocular Nutrition Society (formerly the Optometric Nutrition Society) as sponsors....which is always a good thing!!

Jeff
(President of ONS!)

Diane -

I apologize for my comment. I think I'm becoming a cynical old man.

In my mind, Flora-Glo Lutein from Kemin is the GOLD STANDARD in lutein supplements. I wish the good folks at Kemin would market their own, branded lutein/zeaxanthin supplement. When I make a recommendation for a stand-alone lutein supplement, I have no idea of the quality/bioavailability of the product the patient is purchasing at the pharmacy/big-box store.

I know that Flora-Glo lutein is in the Preservision/AREDS products from Bausch & Lomb. What other companies are using your product?

[John L Henahan]

Kent,

I use Macula Complete from Biosyntrx. They use Kemin's product and include ALL the nutrient co-factors that support a healthy retina. This is unlike some "focused" products that just offer a few ingredients.

They also support the Ocular Nutrition Society (formerly the Optometric Nutrition Society) as sponsors....which is always a good thing!!

Jeff
(President of ONS!)

Do you have a link for this? Also a link for ONS would be cool

[Jeffrey Anshel]

Sure:
www.biosyntrx.com

www.ocularnutritionsociety.org

thanks
Jeff

[Uduak Udom]

Kent,
If you would like brochures for your practice, just send me an email (diane.alexander@kemin.com) and we will send you some free of charge

http://www.floraglolutein.com/KHMKTC...c_Brochure.pdf

Thanks your support of the brand.

Diane

Can the brochures be sent outside the US, or will H&S apply?

[Jeffrey Anshel]

The ONS has chairside brochures also, which we sell at cost to our members. They discuss the overall importance of good nutrition (including supplements) to eye health. The Kemin brochures are well done too.

We've been talking to Kemin about joining us as sponsors of the ONS, because our missions are very much in line with each other.

Eventually, we hope!
Jeff

[Kent Juffer]

Diane or Jeff,

There are differences in opinion as to the adequate daily dosage of lutein. What seems to be the consensus .... 6, 10, or 20 mg./day?

Kent

[Jeffrey Anshel]

Kent,
Well, I honestly don't think there is a magic number out there. Most of the studies originally suggested 6mg, then it went to 10, then 16, now some are 20. There are several factors which may dictate what "magic number" you might want to target.
Genetic factors- are the susceptible to AMD?
Diet- still into junk food and few dark, leafy green veggies?
Weight- over??
Lifestyle- smoker?
Other supplements- taking zeaxanthin?

AREDs II is using 10 mg along with 2 of zeaxanthin. Some formulations go up to 4mg of Z (max. that they can use due to proprietary patents).

Also, are you testing your patients with either the Quantifeye or Macuscope units to get a subjective rating on their MPOD? That would help you decide if you need to supplement at all too.

With all that said, you might consider going with 16 or 20mg (amounts as high as 200mg have been tested with no negative side effects).

Hope that helps- imagine how much more you'd have available to you if you renewed your ONS membership!!! ;-)

Jeff

[Diane Alexander, Ph.D.]

Can the brochures be sent outside the US, or will H&S apply?

We can ship them outside the US but they will not have a list of the supplements that contain FloraGLO. The supplements that we list are only found in the US and Canada, so we would send brochures without the supplement list. Also, keep in mind the brochures are only available in English and Spanish.

If you are interested in receiving some brochures, just send me an email at diane.alexander@kemin.com.

Thanks for your interest!

[Diane Alexander, Ph.D.]

Today most clinical studies are using 10 mg of lutein. There are also numerous product on the market containing 20 and even 40 mg. However, it is very important to understand that all lutein is not the same. FloraGLO contains purified, crystalline lutein also known as free lutein. Lutein can also be found as a lutein ester. Lutein esters have one or two fatty acid chains attached via an ester bond to the two hydroxyl groups on the lutein molecule.

• Free lutein is directly absorbed by the body.
• Lutein esters must be deesterifed by enzymatic reactions in order to be absorbed in the body. The rate at which this conversion occurs is unknown.
• Thus, it is not possible to estimate the bioavailability of lutein esters as the rate of conversion of lutein esters to free lutein is not known.

If a product contains lutein esters, it should be indicated on the label. Thus, it is important check the label to make sure that the product specifically states lutein (not lutein esters) to ensure that you are getting a quality lutein ingredient brand that is easily absorbed by the body. Look for FloraGLO in the ingredient list since it is the lutein ingredient brand used in the majority of clinical studies worldwide.