There was a time in this country when the vegetables produced on farms had nutritional value and indeed they still do on small farms.  However, most of the vegetables we now eat are produced by farming conglomerates bent on extracting the most profit that they can from every acre of land.  The land is replanted without much rest and the crop is picked long before it ripens.  As a result, there  is little nutritional value in the fruits and vegetables we eat.  I think if we were to follow the minimum daily requirement as posted by government, we would be eating all day just to keep up.

For many years the American Medical Association was not in favor of nutritional supplementation but in 2002 they came around and in essence are agreeing with the notion that the nutritional value of food has declined and supplements may play a role in preventing cancer, heart disease, depression, and macular degeneration. 

Omega-3 fatty acids are emerging as an important supplement in the prevention of numerous eye related conditions.  Studies have shown that there is almost a 70% reduction in dry eye syndrome in women who consume five to six servings of tuna per week.  Tuna contains large quantities of omega-3.  Also, if you take in large amounts of omega-3, it tends to nutrilize the inflammatory effect of omega-6.  I would (although not studied) add flaxseed as a source of the omega-3. 

Cataract formation may be altered by the intake of lutein and zeaxanthin as demonstrated in the Carotenoids in Age-Related Eye Disease Study (AREDS).  As light passes through the lens of the eye for a lifetime, it stands to reason that the protein in the lens would be damaged (thus forming cataracts) by free radicals.  Carotenoids are strong antioxidants which nutrilize the free radicals.

Age related macular degeneration (ARMD) is a vision limiting condition which aflicts seniors.  The incidence will probably rise to near epidemic proportions as the population ages.  The AREDS demonstrated that folks taking lutein and zeaxanthin have a 35% to 55% reduction in the risk of both atrophic and neovascular ARMD.  The same study identified that omega-3 fatty acids will decrease the risk of the progression of ARMD.

There are numerous supplements on the market and you should consult your physician prior to taking any of them.  The AREDS study employed Ocuvite marketed by Bausch and Lomb so that is the standard.  It comes with and without zinc.  It does not contain omega-3 fatty acids, in which case that would be taken along with Ocuvite. 

There is little down-side risk to taking nutritional supplements.  If you get started taking them early in life you may reap the rewards later.  We all want to live well as long as we can and supplements may be one of the answers.