I see Shizzo but you're preaching it like all people with poor vision, is a result of genetics. This is not true. First, your study states nearsightedness. Next, this is not the case for all nearsightedness. Poor vision, is the result of poor diet. You may be eating totally clean and you can still be eating a poor diet. How you say? If the food you eat lacks the necessary minerals you need to keep your body at peak health, it's a poor diet. Most people in the U.S. including myself have a poor diet. Why? We eat hybrid foods number 1. What is a hybrid food? Good question. It's a food not found in nature. A crossbred food. Examples: Common hybrid fruits include the following:
Seedless apples
Seedless watermelons
Several varieties of dates
Seedless grapes
Seedless watermelons
Seedless pineapples
Seedless persimmons
Common hybrid vegetables include the following:
Carrots
Corn
Beets
Celery
Potatoes
Cauliflower
Common hybrid beans, nuts, and seeds include the following:
Legumes
Soy
Wheat grass
Wheat
Rice
Oats
Cashews
Common hybrid herbs include the following:
Ginseng
DonQuay
Chamomile
Garlic
Goldenseal
Echinacea
These foods aren't outright unhealthy but they're incomplete and some of them high in starch and sugar and the body doesn't completely use it.
When your diet consists of these foods and other acidic foods and the way it's prepped (meat and microwaves) you have a poor diet that will lead to a host of conditions over time. Food needs to be complete foods so there's no mineral deficiencies. Complete foods are alkaline in nature and not starchy and high in sugar. This acidic food causes the deterioration of the mucus membranes which brings on disease and ailments.
So by your comments, almost everyone on earth should have eye problems then. The people that were born with (or the genetic trait to develop) bad vision, had a defect that would hinder them in life. I only talked about Nearsightedness, but Farsightedness is also a passed family trait. My whole point, was that having bad vision a hundred thousand years ago, could very well have meant living or dying. How good would a Roman soldier have been with a bad case of nearsightedness? We have made many advances in medicine, science, and technology that allow us to live longer than ever before.
We no longer have to worry about things like basic bad vision (for the most part) in developed countries. That would have been a huge concern for anyone before the tech existed.
From Wiki:
The first eyeglasses were made in Italy at about 1286, according to a sermon delivered on February 23, 1306, by the Dominican friar Giordano da Pisa (ca. 1255–1311): "It is not yet twenty years since there was found the art of making eyeglasses, which make for good vision...And it is so short a time that this new art, never before extant, was discovered...I saw the one who first discovered and practiced it, and I talked to him."
Wiggs, try going through the dark ages without glasses

Imagine 10,000 B.C. being farsighted