Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Omega-3 fatty acids appear to impact AMD progression

22.06.2009
Omega-3 fatty acids found in fatty fish such as tuna and salmon may protect against progression of age-related macular degeneration (AMD), but the benefits appear to depend on the stage of disease and whether certain supplements are taken, report researchers at the Laboratory for Nutrition and Vision Research (LNVR), Jean Mayer USDA Human Nutrition Research Center on Aging (HNRCA) at Tufts University.

The researchers calculated intakes of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) from dietary questionnaires administered to 2,924 men and women, aged 55 to 80 years, participating in an eight-year supplement trial, the Age-Related Eye Disease Study (AREDS) of the National Eye Institute (NEI).

The AREDS trial results suggest taking supplements of antioxidants plus zinc prevents progression of late-stage AMD. AREDS study participants were randomly allocated to receive either a placebo or supplements containing the antioxidants vitamins C and E and beta carotene, the minerals zinc and copper, or a combination of both.

"In our study, we observed participants with early stages of AMD in the placebo group benefited from higher intake of DHA, but it appears that the high-dose supplements of the antioxidants and/or the minerals somehow interfered with the benefits of DHA against early AMD progression," says senior author Allen Taylor, PhD, director of the LNVR at the USDA HNRCA. Taylor is also a professor at the Friedman School of Nutrition Science and Policy at Tufts and Tufts University School of Medicine (TUSM).

The antioxidant supplements did not seem to interfere with the protective effects of DHA and EPA against progression to advanced stages of AMD. Participants who consumed higher amounts of DHA and EPA appeared to have lower risk of progression to both wet and dry forms of advanced AMD. The results are published on-line ahead of print in the British Journal of Ophthalmology.

"Data from the present study also shows the supplements and omega-3 fatty acids collaborate with low-dietary glycemic index (dGI) diets against progression to advanced AMD," says corresponding author Chung-Jung Chiu, DDS, PhD, a scientist in the LNVR and an assistant professor at TUSM. "Our previous research suggests a low-GI diet may prevent AMD from progressing to the advanced stage. We hypothesize that the rapid rise of blood glucose initiated by high-GI foods results in cellular damage that retinal cells cannot handle, thus damaging eye tissues."

dGI is a scale used to determine how quickly carbohydrates are broken down into blood sugar, also known as blood glucose. Foods such as sweetened drinks, sodas and white bread are high-GI because they trigger a sharp rise and fall of blood sugar. Low-GI foods, such as whole grain versions of pasta and bread, have a milder effect on blood sugar response. Earlier data published by Taylor and Chiu suggests that daily substitution of five slices of whole grain bread for white bread out of a total intake of 250 g of carbohydrate might cut out almost 8% of advanced AMD over five years. This is readily achievable with little diet behavior modification.

Eating two to three servings of fatty fish such as salmon, tuna, mackerel, shellfish, and herring every week would achieve the recommended daily intake of DHA and EPA. However, the majority of AREDS participants and Americans eat a much lower level than recommended. "If changing dietary habits is not easy, supplementation is an option," says Chiu.

The authors stress it is still premature to conclude dietary recommendations for people with AMD and more studies are warranted. "Taken together, these data indicate that consuming a diet with higher levels of omega-3 fatty acids, antioxidants and low-GI foods may delay compromised vision due to AMD," says Taylor. "The present study adds the possibility that the timing of a dietary intervention as well as the combination of nutrients recommended may be important."

AMD is a progressive disease that attacks central vision, resulting in a gradual loss of eyesight and, in some cases, blindness. The NEI reports that AMD is the most common causes of non-remediable vision loss in Americans over 60.

The study was awarded The Association for Research in Vision and Ophthalmology (ARVO)-American Foundation for Eye Research (AFER)/Merck Innovative Ophthalmology Research Award at the ARVO 2009 Annual Conference in May. The award is given to researchers under 45 to encourage research leading to improved quality of life for patients.

The authors received funding for this study from the following: United States Department of Agriculture (USDA), the National Institutes of Health, the Johnson & Johnson Focused Giving Program, the American Health Assistance Foundation and the Ross Aging Initiative.

About Tufts University School of Nutrition

The Gerald J. and Dorothy R. Friedman School of Nutrition Science and Policy at Tufts University is the only independent school of nutrition in the United States. The school's eight degree programs which focus on questions relating to famine, hunger, poverty, and communications, are renowned for the application of scientific research to national and international policy. For two decades, the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University has studied the relationship between good nutrition and good health in aging populations. Tufts research scientists work with federal agencies to establish the USDA Dietary Guidelines, the Dietary Reference Intakes, and other significant public policies.

If you are a member of the media interested in learning more about this topic, or speaking with a faculty member at the Friedman School of Nutrition Science and Policy at Tufts University, or another Tufts health sciences researcher, please contact Andrea Grossman at 617-636-3728 or Christine Fennelly at 617-636-3707.

Andrea Grossman | EurekAlert!
Further information:
http://www.tufts.edu

More articles from Health and Medicine:

nachricht Biofilm discovery suggests new way to prevent dangerous infections
23.05.2017 | University of Texas at Austin

nachricht Another reason to exercise: Burning bone fat -- a key to better bone health
19.05.2017 | University of North Carolina Health Care

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>