Vital Choice Salmon Oil (top left) vs. two standard fish oils

Omega-3s were confirmed as potent eye protectors in a study we summarize elsewhere in today’s edition of "Vital Choices" (see “Omega-3s from Fish Affirmed as Potent Eye-Protectors”).

And in a happy coincidence for lovers of fatty fish – especially wild salmon -- the same journal published research that positions vitamin D as a comparably powerful preventive aid against age-related macular degeneration (AMD).

These findings follow a string of studies linking vitamin D to reduced risks of Alzheimer’s, depression, bone fractures, multiple sclerosis, lupus, fibromyalgia, diabetes, heart disease … and several major cancers. (Visit our archive and search for “vitamin D”.)

As it happens, wild salmon – especially wild Sockeye salmon – are the richest food sources of the “sunshine and seafood” vitamin.

People obtain vitamin D primarily from exposure to UV sunrays. The only whole foods in which it occurs in abundance are fatty ocean-going fish, especially wild salmon. (Farmed salmon contain considerably less vitamin D, according to a recent study; see “Wild Salmon Affirmed as Top Vitamin D Source”.)

Compared with wild salmon (360 to 687 IUs per 3.5 oz serving), fortified milk (100 IU per 8 oz serving) is a significant but much poorer source. In fact, cod liver oil is the only “food” higher in vitamin D.

Vitamin D makes the perfect eye-health fit for omega-3s

The authors of the new study analyzed existing data from the US government’s huge National Health and Nutrition Examination Survey.

Their results indicate that Americans whose blood levels of vitamin D ranked in the top one-fifth were 36 percent less likely to develop “dry” (early stage) AMD, compared with those who ingested the least vitamin D (Parekh N et al 2007).

And they found that fish-lovers enjoyed an even more dramatic 59 percent drop in the risk of “wet” (later stages) AMD: the form that causes eight out of 10 cases of blindness related to either form of the disease.

The researchers -- led by Niyati Parekh, Ph.D. of the University of Wisconsin-Madison -- dug deeper to determine any different correlations between AMD risk rates and intake of the leading food sources of vitamin D:

• Fish-rich diets reduced risk of wet (advanced) AMD by 59 percent: a result consistent with the ability of marine omega-3s to reduce wet AMD risk, reported in today’s accompanying article.
• Vitamin D supplements reduced risk of early, dry AMD in people who did not consume milk daily, which confirms that vitamin D is indeed the eye-health factor common to milk and fish.
• Milk-heavy diets reduced risk of dry (early) AMD by 25 percent.

Dr. Parekh and her colleagues speculated that the beneficial effects of vitamin D might stem from an anti-inflammatory effect and/or by its preventing overgrowth of new blood vessels in the retina, which causes the wet form of AMD.

Omega-3s reduce the risk of both forms of AMD – dry and wet – but excel at stopping the wet form. In complementary fashion, vitamin D seems to specialize at deterring the early, dry form.

Thus, the two make a powerful preventive pair that comes in one delicious package: wild Alaska salmon.

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