In certain developed parts of East Asia, nearsightedness is skyrocketing, with the prevalence of myopia now at an estimated 80 to 90 percent of the population. In areas of the world where families cannot afford eyeglasses, poor vision from nearsightedness is a serious disability that can affect a person’s ability to learn and work.
The authors of the article at Nutrition Research suggest that the better vision of hunter-gatherers as compared to an agrarian culture is related to greater variety and larger quantities of phytochemicals in the H-G group. Here’s their abstract:
Myopia [near-sightedness] is absent in undisturbed hunter-gatherers but ubiquitous in modern populations. The link between dietary phytochemicals and eye health is well established, although transition away from a wild diet has reduced phytochemical variety. We hypothesized that when larger quantities and greater variety of wild, seasonal phytochemicals are consumed in a food system, there will be a reduced prevalence of degenerative-based eye disease as measured by visual acuity. We compared food systems and visual acuity across isolated Amazonian Kawymeno Waorani hunter-gatherers and neighboring Kichwa subsistence agrarians, using dietary surveys, dietary pattern observation, and Snellen Illiterate E visual acuity examinations. Hunter-gatherers consumed more food species (130 vs. 63) and more wild plants (80 vs. 4) including 76 wild fruits, thereby obtaining larger variety and quantity of phytochemicals than agrarians. Visual acuity was inversely related to age only in agrarians (r = -.846, P < .001). As hypothesized, when stratified by age (<40 and ≥ 40 years), Mann-Whitney U tests revealed that hunter-gatherers maintained high visual acuity throughout life, whereas agrarian visual acuity declined (P values < .001); visual acuity of younger participants was high across the board, however, did not differ between groups (P > .05). This unusual absence of juvenile-onset vision problems may be related to local, organic, whole food diets of subsistence food systems isolated from modern food production. Our results suggest that intake of a wider variety of plant foods supplying necessary phytochemicals for eye health may help maintain visual acuity and prevent degenerative eye conditions as humans age.
In the developed world, kids might prevent near-sightedness by basking in the bright sunlight of outdoors or simply by spending time outdoors. I suspect prevention has a lot to do with using our distant vision for hours instead of looking at a screen two feet away or the interior walls of our homes.
Steve Parker, M.D.
Reference: London, D.D. and Beezhold. A phytochemical-rich diet may explain the absence of age-related decline in visual acuity of Amazonian hunter-gatherers in Ecuador. Nutrition Research 2015 Feb;35(2):107-17. doi: 10.1016/j.nutres.2014.12.007. Epub 2014 Dec 31.