You can't develop myopia or hyperopia after your eyes/skull/orbital muscles are done growing. So this suggestion probably applies only to adults.
Keep in mind that this is age-related macular degeneration. Your photoreceptor cells are protected by the α-tocopherol until "a person's 50s or 60s." You wouldn't need any prophylactic interventions until then.
Actually yes. Doctors have told me that I should wait til 25 to see If I am candidate to eye laser operation because that is the average age where people stop developing his muscle eyes.
I don't know about a source—a medical textbook? Those conditions are explicitly caused by the eye being squished out of the "proper" shape for focusing light by the way the skull and extraocular muscles end up developing.
I suppose you could develop myopia later in life as a result of inflammation of the extraocular muscles (orbital myositis), but this would be 1. temporary, and 2. not treated as its own disease, but rather as a symptom.
Keep in mind that this is age-related macular degeneration. Your photoreceptor cells are protected by the α-tocopherol until "a person's 50s or 60s." You wouldn't need any prophylactic interventions until then.