In fact, in my opinion, the eyesight will not get worse with the age. Because I am a girl whose eyesight did not get worse, and now I am 40 years old. If you found that your eyesight is getting worse, I think the main reason is not your age, instead, you did not protect your eyes properly. Like me, I remember that I became nearsighted when I 15 years old, at the same time, I found I am not so beautiful with glasses as without glasses, so I decide to get rid of them. From that day on, I take care of my eyes just like taking care of myself, for instance, making them have a rest when they are tired and giving some eye drops to them when they are dry. Now I can look distance without glasses clearly although I am 40 years old. As a matter of fact, when you found your eyes are not so good as before, I think you should find the reasons from yourself instead of the objective reasons. Hope you can think twice.
It is common that vision becomes worse with the age, but that just for the senior and it often happens as hyperopia. It is because the lentil loses its flexibility and eyes can't focus on objects in short distance. Nevertheless, it seldom happens to middle-aged people or the young. In your case, myopia won't be severe with the time flowing. That your eyesight becomes worse may be aroused by your habit, such as how often and how long you facing the computer, do you often rub your eyes and so on. Form good habit to use your eyes. Keep you eyes away from dirt and eat more carrot and fish oil. These methods make contribution to better vision.
Well, it is normal for your situation to become like that. As we know that m myopia, or shortsightedness, is caused by a growth defect of the eye. We can say the eye is too long for its refractive power. As you get older, your body grows, and that includes the length of your eye in myopic people. The only thing special about your prescription is it's relatively fast growing, but you can expect that to stop fairly soon. Maybe many people will suggest you to wear glasses. But you should know that wearing glasses that are too powerful for you could damage your eyes, because the extra refractive power they would need to use might make you cross eye.
The entry point for light is the cornea, the transparent tissue in the very front of the eye that functions as the window through which all light has to pass on its way to forming a visual perception. Next, the light signal encounters the lens, which focuses it finely on the third structure of the eye: the retina. The retina is analogous to the film in the back of the camera. It is on the retina that the light is converted into a neural signal that is ultimately interpreted by the brain as an image. Finally, the optic nerve, which carries these signals to the brain, functions like a cable that connects the video camera to the television screen. The deterioration of our vision with age is invariably the result of a problem with one of these four structures.