Wednesday, November 28, 2007 Uncontrolled potency, Part 2 By Zosimo T. Literatus, R.M.T. Breakthroughs
LAST WEEK, you had a close look of age-related macular degeneration (AMD). Today, you will learn how common antioxidants affect AMD development.
Researcher Elaine T Chong and colleagues published their findings on AMD in the Oct. 13 issue of the British Medical Journal.
They made a very wide review of previous studies (meta-analysis) from seven databases consisting of 4,192 abstracts. Of these, only 12 studies qualified in their stringent review standards. These studies included close to 150,000 people with 1,878 early AMD incidences, followed up for an average of nine years (range: five to18 years).
Chong and colleagues Tien Y Wong, Andreas J Kreis, and Robyn H Guymer are scientists at the Centre for Eye Research Australia in the University of Melbourne (Victoria, Australia). Another colleague Julie A Simpson works at the Centre for Molecular, Environmental, Genetic and Analytic Epidemiology at UM.
The antioxidants used in these studies include vitamin A, vitamin C, vitamin E, zinc, lutein, zeaxanthin, alpha-carotene, beta-carotene, beta-cyrptoxanthin, and lycopene.
Vitamins ACE and trace mineral zinc are very popular already, and are found in many over-the-counter supplement pills as well as from fruits and vegetables, perhaps need no further mention here.
However, the rest might need more description to make them familiar to the reader.
Lutein is one of the pigments responsible for the yellow color in egg yolks. It can also be found in some algae and in many plants. The other pigment is zeaxanthin, an antioxidant found also in corn.
Carotenoids, such as alpha- and beta-carotenes, are good filters of harmful blue light and their antioxidant properties have been demonstrated in test tube experiments.
These are organic chemical compounds that give yellow, orange, or red color to plants. It includes phycoerythrin, a red pigment found in red algae; and lycopene, the pigment causing the red color of tomatoes.
The results indicated that the antioxidants being studied had little or no preventive or curative effect on AMD. “Inconsistency in results,” explained Chong, “implies uncontrolled oxidative chain reactions of reactive oxygen species occurring in eyes with AMD at early or intermediate stage.”
And yet, positivism can be the road to hope. “For there is good news yet to hear and find things to be seen,” wrote G. K. Chesterton in the Rolling English Road. “Before we go to Paradise by way of Kensal Green.”
