Eye functiondeclines with age.

The retina is equivalent to the film in a camera. The macula, a crucial part of the retina, is protected by yellow pigments called lutein and zeaxanthin. However, as we age, the amount of these yellow pigments decreases, and prolonged exposure to strong ultraviolet light can lead to age-related macular degeneration. Recently, the effects of blue light emitted from computer and smartphone screens have also been pointed out.
Age-related macular degeneration was once thought to be relatively uncommon in Japan, but it has increased dramatically in recent years due to the aging population and the Westernization of lifestyles, and is now the fourth leading cause of blindness.

Blood vessels are vital organs that deliver nutrients. However, as we age, blood flow deteriorates, and the ability to deliver nutrients decreases.
Tears not only moisten dry eyes, but they also help us see things clearly by creating a uniform layer on the surface of the cornea. As we age, tear production decreases, and the corneal surface becomes uneven, causing light to scatter instead of entering directly, leading to glare, eye fatigue, and blurred vision.

The ciliary muscle, which controls focus, is essential for adjusting focus. To focus on nearby objects, you need to tense this muscle. As we age, this muscle weakens and becomes less tense, making it difficult to focus on nearby objects. This is one of the causes of presbyopia (age-related farsightedness).

The eye adjusts focus by changing the thickness of the lens. To focus on near objects, the lens becomes thicker, and to focus on distant objects, it becomes thinner. The lens is mainly made of protein, and as it loses its elasticity, it can no longer thicken, making it difficult to focus on near objects. This is one of the causes of presbyopia.