Eye floaters are common visual disturbances that appear as small specks, threads, or cobwebs drifting across your field of vision. These shapes are actually tiny shadows cast upon the retina. The debris casting these shadows consists of microscopic clumps of collagen fibers or cells suspended in the clear, gel-like substance that fills the eyeball, known as the vitreous humor. While the floaters themselves are typically permanent, the severity of how often you notice them changes daily. This variation depends on both external environment and internal physiological factors.
Why Contrast Makes Floaters Appear Worse
The visibility of existing floaters is highly dependent on the amount of light entering the eye and the background against which you are looking. Floaters are most noticeable when the background is uniform and brightly illuminated, such as a clear blue sky, a white wall, or a brightly lit computer screen. This high-contrast environment maximizes the shadow cast by the debris onto the retina, making the subtle shapes stand out dramatically. Conversely, when you look at a complex, dark, or dimly lit background, the shadows are diffused or obscured, making the floaters seem to disappear. This fluctuation in perception gives the impression that the floaters are “worse” on some days, when the debris has simply moved into a position that catches the light more effectively.
Internal Factors That Affect Visibility
Beyond external lighting, subtle physiological shifts within the body can temporarily increase your awareness of floaters.
Hydration Status
One major influence is the body’s hydration status. While dehydration does not create new floaters, inadequate water intake can slightly alter the consistency of the vitreous gel. This alteration potentially causes existing clumps to become more concentrated or noticeable.
Stress and Fatigue
Stress and fatigue play a role by heightening your overall visual awareness. When the eyes are tired or strained, the brain’s ability to filter out visual “noise,” such as floaters, is diminished. Furthermore, stress hormones like epinephrine can cause pupils to dilate, allowing more light to enter the eye. This inadvertently makes the shadows of the floaters more visible against the retina.
Ocular Irritation
Temporary ocular irritation, such as that caused by seasonal allergies or mild inflammation (uveitis), can also make floaters more prominent. Inflammation may introduce additional cells or debris into the vitreous or simply increase the eye’s overall sensitivity.
When to Seek Immediate Medical Attention
While the daily fluctuations in floater visibility are usually harmless, certain acute changes can signal a serious, vision-threatening event, such as a retinal tear or detachment. You should seek immediate medical attention from an ophthalmologist if you experience a sudden, dramatic increase in the number of floaters, often described as a “shower” or “swarm” of new specks. This increase is particularly concerning when accompanied by the sudden appearance of flashes of light, known as photopsia. Flashes occur when the vitreous gel is tugging on the retina, which can lead to a tear. A third sign requiring emergency care is a persistent shadow, like a dark curtain or veil, moving across your field of vision. These symptoms indicate that the retina may be separating from the underlying tissue, requiring prompt treatment to prevent permanent vision loss.