Optimising dietary modification for age-related macular degeneration (AMD)

Abstract

An ageing population has raised the priority of reducing the risk for age-related eye diseases that impair sight and quality of life. Chief among these diseases is age- related macular degeneration (AMD), the leading cause of visual impairment among older adults in the developed world. The dietary xanthophylls lutein and zeaxanthin may be effective at attenuating the risk and/or progression of AMD due to their antioxidant and photo-protective properties in the macula, where they are known as the macular pigment. The macular pigment is entirely of dietary origin therefore it is important that AMD patients adopt appropriate dietary modification. Currently, there is a lack of information regarding the lutein values of specific xanthophyll containing food sources. A lab based investigation was undertaken to determine the lutein concentrations in kale by high-performance liquid chromatography (HPLC); information was established that may improve knowledge on the climate and post-harvest handling, processing and storage effects. Lutein concentrations in minimally processed kale were significantly lower (p<0.001) than that of kale freshly harvested. Domestic cooking and storage also had substantial negative effects on kale lutein levels. A dietary analysis study and a qualitative based study were conducted to determine dietary habits in AMD patients. In align with previous work, AMD patients were found to be under consuming nutrients regarded as important for their condition. Subjects consumed an average of 1.7 mg of L and Z per day, and calorie intakes were significantly below government DRVs (p<0.05). Further investigations suggested that this may be attributed to certain physical and psychosocial barriers. Using the results of the laboratory based study, ready meals were created as a novel intervention to improve diet in this population. This body of research adds insights into dietary interventions within visually impaired groups, studies embedded may enrich dietary advice in the context of AMD.