Age-related macular degeneration (AMD) is a progressive disorder primarily affecting the macula, the central region of the retina involved with central vision. It is the leading cause of blindness in developed countries, accounting for 50% of blindness. Some risk factors are not reversible (genetics, age, darker iris pigmentation, previous cataract surgery, and hyperopic refraction), while others are considered reversible (smoking habit, obesity, incorrect diet). Among macronutrients, alcohol intake and food’s glycaemic index appear to be the strongest AMD risk factors. However, the most investigated protective factors for AMD are micronutrients, and in particular antioxidants (especially carotenoids), minerals (especially zinc), polyunsaturated fatty acids and vitamin D. The Age-Related Eye Disease Study (AREDS) was the first large-scale randomised controlled clinical trial to demonstrate the benefit of vitamin and mineral supplementations in preventing the progression to advanced AMD. The AREDS formulation included antioxidants such as vitamin C 500 mg, vitamin E 400 IU and β-carotene 15 mg, associated to zinc (zinc oxide 80 mg and cupric oxide 2 mg). This level of antioxidants and zinc was considerably higher than the amount in any daily multivitamin supplement and it is difficult to achieve from diet alone. In conclusion, modifying environmental factors is currently the only approach to reduce the genetic risk of AMD. Clinicians should provide dietary advice and, in particular, prescribe evidence-based dietary supplements to susceptible individuals to postpone or prevent the vision-disabling consequences of AMD.
Diet, dietary supplements and age-related macular degeneration (AMD)
CICERO, ARRIGO FRANCESCO GIUSEPPE;TARTAGNI, ELISA
2014
Abstract
Age-related macular degeneration (AMD) is a progressive disorder primarily affecting the macula, the central region of the retina involved with central vision. It is the leading cause of blindness in developed countries, accounting for 50% of blindness. Some risk factors are not reversible (genetics, age, darker iris pigmentation, previous cataract surgery, and hyperopic refraction), while others are considered reversible (smoking habit, obesity, incorrect diet). Among macronutrients, alcohol intake and food’s glycaemic index appear to be the strongest AMD risk factors. However, the most investigated protective factors for AMD are micronutrients, and in particular antioxidants (especially carotenoids), minerals (especially zinc), polyunsaturated fatty acids and vitamin D. The Age-Related Eye Disease Study (AREDS) was the first large-scale randomised controlled clinical trial to demonstrate the benefit of vitamin and mineral supplementations in preventing the progression to advanced AMD. The AREDS formulation included antioxidants such as vitamin C 500 mg, vitamin E 400 IU and β-carotene 15 mg, associated to zinc (zinc oxide 80 mg and cupric oxide 2 mg). This level of antioxidants and zinc was considerably higher than the amount in any daily multivitamin supplement and it is difficult to achieve from diet alone. In conclusion, modifying environmental factors is currently the only approach to reduce the genetic risk of AMD. Clinicians should provide dietary advice and, in particular, prescribe evidence-based dietary supplements to susceptible individuals to postpone or prevent the vision-disabling consequences of AMD.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
