The question contains a goal and a method, but only the method does not work. Healthy eyes differ from patients not in that patients are not focused there, but in that healthy ones are able to change focus, and patients do not. Atrophied muscles can only be revived using them. It is important to know that there are 2 irreconcilable camps among doctors. Helmholtz supporters sell glasses, and Bates supporters teach exercises that return muscles to normal function. But exercise cannot be bought like blueberries and carrots, you have to do them.
Carrots and vision.
As it turned out, the only link between carrots and vision is vitamin A, which the body gets from beta - carotene. You can consume a lot of vitamin A, but it will not improve your vision in any way. If the body is severely deficient in vitamin A, this can be one of the causes of vision loss. The source of the appearance of the medical myth about the connection between carrots and vision is unknown, but according to one version, it appeared during the Second World War, as an explanation for the sharp jump in the effectiveness of night flights. In fact, efficiency has increased thanks to the new radar system.
Why do we even say that carrots are good for eyesight? The fact is that it contains a large amount of vitamin A (just like blueberries). It, in turn, is necessary for the functioning of light-sensitive cells in the eyes.
The most common problem associated with a lack of vitamin A, as Eugene said, is night blindness. With this ailment, the ability to see in the dusk is sharply reduced, since the light-sensitive rods lack rhodopsin (visual pigment), which can only be synthesized from vitamin A.
Vitamin A may or may not be enough. If you do not experience problems with the perception of light and color, then you (or rather your eyes, because the body needs it, not only the eyes) have enough of it, and no longer need it.
Vitamin A is fat-soluble and accumulates in organism. Unlike, for example, vitamin C, which, being water-soluble, is excreted from the body naturally and needs to be replenished daily. For this reason, excessive consumption of vitamin A leads to poisoning, liver problems, and the person literally turns yellow.
Even when the heels and palms turn yellow from carotene, vision will not improve. Vitamins in carrots and blueberries only reduce the likelihood of certain diseases, such as night blindness. These and any other vegetables and fruits will not be able to correct the refractive characteristics of the eye (this is what is called "minus" or "plus").