8 Reasons Why Your Eyes Can Change Color

Description: The article discusses eight main causes that can affect the change in eye color in humans. From exposure to sunlight and hormonal fluctuations to the effects of injuries and age-related changes, all this forms a complete picture of why the color of our iris can change.



Introduction
Eyes are a unique “mirror of the soul” and one of the key factors shaping our appearance. Therefore, many of us are puzzled if suddenly notice that the shade of the iris changes. It happens that someone notices a light color in their childhood photos, and in adulthood the eyes seem darker. Or perhaps people notice that under certain lighting, the eyes become greener or browner. In some cases, these changes are quite normal, and sometimes can be a signal of internal processes in the body. In this article, we look at eight main reasons why a person’s eyes can change color, from harmless external factors to signals of possible medical problems. If you also wondered why you or your loved ones suddenly change the shade of the iris, read on: perhaps you will find an explanation.

Main part
1. Natural age-related changes
In newborns, the phenomenon of “uncolored” or bluish eyes is often observed: just the pigment has not yet accumulated in the iris. Over time, during the first few months (or even years) of life, a more saturated color is formed in the iris due to melanin. Parents often note that the child had blue eyes, and by the age of three became brown or green. This is quite normal, because the genetically laid melanin level does not “manifest” immediately. Elderly people also have the effect of losing eye color saturation when the iris lightens slightly with age. This is due to changes in the structure and number of pigments. Basically, these changes are not dangerous, although sometimes they can indicate age-related ophthalmic changes, for example, associated with diseases (glaucoma, cataracts). But in general, smooth darkening or brightening is a natural evolutionary process.

2. Changes in lighting and reflection
Sometimes the color of the eyes seems different just because of the lighting. The iris is able to reflect light, and with bright daytime sun or in a room with a specific backlight, the shade may seem saturated or closer to gray. The more light, the more contrasting the colors. Also, clothes and makeup, reflecting and refracting light, emphasize some tones of the iris and “muffle” others. As a result, people with eyes in which several pigments are mixed (for example, brown-green), can notice the effect of the “chameleon” – the eyes appear either greener or browner. So when someone notices a “magic” change, it’s often just a play of light and reflection.

3. Emotional reactions and physiological fluctuations
An interesting observation: our emotions (fear, anger, joy) can slightly affect the dilation or narrowing of the pupil. When the pupil is dilated (for example, with arousal, adrenaline surge), it seems that the color of the iris becomes deeper or darker. And when the pupil narrows, the pigment of the iris is more noticeable, and the shade may look brighter, or, conversely, if the eye is dark, the pupil can merge, creating the illusion of a lighter environment. Also, hormone levels (for example, in women during pregnancy and menopause) can indirectly affect pigmentation or vascular changes in the eye. True, these effects are usually extremely small, but some people with sensitive iris notice that with strong emotions, the color of the eyes seems to change.



4. Effects of sunlight
The sun affects not only our skin, but also our eyes. Of course, the iris does not “tan” in the same way as the skin, but with prolonged and frequent exposure to ultraviolet light, subtle changes in the cells that produce pigment occur. And although a sharp darkening or brightening should not be expected, some shift in hue can be noticed - especially in people with light eyes, more susceptible to such changes. An interesting fact is that some peoples living in regions with bright sun are dominated by darker iris, which gives them better screening from the abundance of light. But this is predominantly an evolutionary genetic trait. But at the individual level, ultraviolet light can “correct” pigmentation by a fraction of a percent, sometimes changing the hue to a warmer one. However, it is still important to protect your eyes from direct bright rays - ultraviolet light can cause photochemical damage (including an increased risk of cataracts), so the use of high-quality sunglasses is very desirable.

5. Injuries, operations and medications
Some eye injuries (strong blows, penetrating wounds, iris surgery) can cause persistent color changes. For example, if the pigment epithelium of the iris is damaged, the eye may appear lighter or darker in one of the areas, creating what is known as "sectoral heterochromia." Also, some eye drops (especially prostaglandin-based drugs used for glaucoma) often contribute to increased pigment and make the iris darker (most often brownish), especially in people with lighter eyes. This is not always a reversible process, so treatment under the supervision of an ophthalmologist is critical. These changes are unexpected, but they are a medically fixed side effect.

Also, surgery to implant artificial iris (exotic procedure to change eye color for aesthetic purposes) can lead to complications if performed poorly. By the way, doctors often warn against such interventions, indicating the risk of deterioration of vision and the development of glaucoma.



6. Age "rainbow" arc and cholesterol deposits
In some elderly people on the periphery of the iris, a light (white or bluish) rim is formed - this is the so-called arcus senilis (age corneal arc). It gives the impression that the color of the eyes changes, although in fact there is a deposition of lipids in the cornea. Also, similar changes occur in people not so older, if there are violations in lipid metabolism.

Such a ring does not change the overall pigment of the iris, but visually it seems as if a person has a “different iris”. Usually, arcus senilis itself does not interfere with vision. However, when such an arc appears at a young age, it is advisable to check cholesterol levels, as this may be an indirect sign of hyperlipidemia. The ophthalmologist during the examination also helps to clarify the nature of this ring.

7. Hormonal changes and stress
Some patients note that under severe and prolonged stress they appear subtle changes in the color of the eyes - the iris becomes duller, more grayish or, conversely, a brighter shade due to changes in vascular reaction. Scientists attribute this to the hormonal background: high levels of adrenaline or cortisol can affect the vessels of the iris. Although statistical mass studies on this topic are not so much, in some clinical observations there are similar descriptions. Similarly, pregnancy, childbirth, menopause – all this leads to fluctuations in hormones, which sometimes slightly adjusts the shade of the eyes (usually very slight, but still noticeable).

Of course, changes are often so subtle that a person can notice them only by directly comparing before and after. But the fact remains that our eyes respond to internal processes, and stress is also one of the causes.

8. Genetic factors and rare heterochromia
Heterochromia (when one eye of another color or in one eye several color zones) is a rare but spectacular feature. There is congenital heterochromia due to genetic reasons, or acquired (due to injuries, tumors, inflammation). Sometimes heterochromia does not appear from birth, but is formed gradually if the pigment changes in one eye due to local factors.

From an evolutionary perspective, such variants do not carry much advantage or disadvantage (although they may be associated with some syndromes). But in social terms, heterochromia always causes curiosity, as it visually attracts attention. The observation that “the eyes began to differ from each other” may be a sign of some internal changes, and then it is better to check with an ophthalmologist.

Conclusion
Eyes can change color for a variety of reasons, from the trivial effect of lighting to serious hormonal or traumatic factors. Some of the changes are completely harmless: people notice that in the sun the eyes appear brighter, in a dark room – darker. Some are related to normal age processes or heredity. However, sudden changes in hue or persistent heterochromia may indicate medical problems and require a visit to an ophthalmologist.

Understanding the range of causes – from the sun’s rays and hormonal fluctuations to the consequences of injuries and medications – it is easier to treat such changes soberly and without panic. Most often we are talking about minor fluctuations due to the mechanics of light or slight changes in the pigment. However, with a strong and unexpected change, it is important to exclude pathology. But regardless of the reasons, our eyes remain unique, with a unique combination of pigments, and a slight change in shade only emphasizes their special expressiveness.

Glossary

• IrisThe colored part of the eye surrounding the pupil. Its color is determined by the content and distribution of melanin pigment.
• melanin: pigment responsible for coloring the skin, hair, iris of the eyes. The more melanin, the darker the color.
• heterochromiaA different color of the iris of the left and right eye or a heterogeneous color within the same eye.
• Arcus senilis: a whitish ring (lipid deposition) along the periphery of the cornea, more often in the elderly.
• Photochemical damage: cell damage (for example, on the retina or in the epithelium) under the influence of intense ultraviolet radiation.
• cataractA disease in which the lens of the eye becomes cloudy, leading to poor vision.
• prostaglandins: a group of physiologically active substances, some of them are used in eye drops for glaucoma; can affect the pigmentation of the iris.
• Chameleon syndromeAn informal name for a phenomenon where the eyes seem to change hue depending on lighting or surroundings.