From the moment a baby is born, and during their first year of life, the changes they go through are amazing and happen very fast.
If you track the changes of a baby in pictures, you will notice that a newborn baby looks completely different when they turn 2 or 3 months old; and if you compare that to when the baby turns nine months, it can be as if you’re looking to a totally different child. One of those changes is eye color.
When do baby’s eyes change color? A baby’s eye color when they’re born is most likely going to change in time, and you’ll be able to see the final baby eye color once they reach the 12-month mark (in some cases, they’ll still experience some changes up until they’re three year old, but those tend to be more subtle).
So before you go overboard with buying outfits and accessories to accentuate your baby’s eye color, read this article.
What defines eye color and when do baby’s eyes change color?
To understand how eye color works, we need to dive into Biology. To simplify it, the human iris (the colored part of the eye) contains cells called melanocytes responsible for producing melanin.
By definition, melanin is the substance responsible for the pigmentation in a person or an animal’s hair, eye, and skin color. The more presence of melanin, the darker your eyes, hair, and skin will be. The amount of melanin in a person will depend on genetics and light exposure from your ancestors.
Melanocytes respond to light, and that’s why babies’ eyes change color after they’re born because as a response to the light, the melanocytes add more melanin to the iris. Because of the exposure to light outside the womb, babies’ eyes change color for the first time when they’re about 3-6 months old, but that color can’t be considered definite until they’re at least nine months old.
By the time your baby is 12 months, they may have a totally different shade of eye color from when they were born, and there’s the slight chance that it changes its hue to a more definite one when they’re three years old.
Here’s a fun fact about baby eye color and melanin: babies are born with a reservoir of melanin behind their irises that will ultimately determine their permanent eye color. Melanin is not developed over time. Also, melanin is brown, and that’s why the eye color normally darkens over time, not lightens, and that’s why eyes that are dark when the baby is born will stay dark. And if the baby is born with blue eyes, they may not stay blue and may turn green hazel, or even dark brown.
With this said, there’s one main factor that will determine the amount of melanin that will derive in the permanent eye color: genetics.
Genetic background of eye color
According to the American Academy of Ophthalmology, human eye color is determined by multiple genes. While there’s extensive research and information about what determines the most common eye colors (brown, blue, and green), there’s still a lot to be learned about other shades such as hazel, bluish-gray and other combinations.
Up until recently, it was believed that a baby’s eye color could be predicted based on the color of the parent’s and grandparent’s eyes. But it’s been proven to be more complicated than simply calculating the odds of dominant and recessive genes because there are other genes at play as well. It’s been determined that in the case of eye color, the passing of genetic traits is very complex, and that’s why you may find that the child of two blue-eyed parents can have brown eyes.
Peer-reviewed studies have shown about 15 genes associated with eye color, including the OCA2 and the HERC2. Predicting the exact color a person’s eyes will be is a gamble, but some cues indicate probability, and there’s even a color chart for this.
For example, if both biological parents have brown eyes, the baby’s eyes will likely be brown, and the same reasoning applies to children where both parents have blue or green eyes. In cases where one parent has blue eyes, and the other has brown eyes, there’s a 50-50 chance that the baby’s eyes will be either brown or blue. Again, the same reasoning applies if one biological parent has green eyes and the other blue eyes.
However, if one parent has green or blue eyes and the other has brown eyes, things get complicated because brown eyes are considered to come from a dominant gene and therefore have more chances to be the final color.
Finally, there are the grandparent’s genes to be considered because even if they’re not dominant, recessive genes may skip a generation or two, but there’s still the chance they make an appearance. And that’s why you may find a blue-eyed baby from two brown-eyed parents.
And did you know that your eye color is as unique as a fingerprint? That’s because the amount of melanin in your iris and the way it’s distributed is unique to each person, no matter if you share the same eye color with other members of your family.
Here are some interesting facts about eye colors:
- The most common eye color in the world is brown, and more than half of the world’s population has it in different shades. Some sources state that 79% of people have dark eyes, which is why brown eye color is considered dominant.
- Blue eyes, which are not very common, get their color from scattered light, just like the water and the sky get their blue color. There’s no blue pigment (or green) because melanin is brown, so in reality, people with blue eyes have minimal pigment in the front layer of the iris. This causes the fibers in the iris to scatter and absorb the longer wavelengths of light, and when they reflect the light out, the eyes appear blue.
- Green eyes are the rarest eye color, and only 2% of the world’s population have them (there are multiple opinions on the actual percentage, but still, green is an uncommon color). This eye color results from the amount of melanin in the iris and how the light scatters off the eye. Basically, green eyes are an optical effect of light scattering. And it has so many different shades because how much melanin is present is unique in each case.
- When there’s no presence of melanin, or the bare minimum, in the skin, hair, and irises, the person is considered to have a condition called albinism. In these cases, their eyes can be either light blue (if there’s some melanin in them) or even pink or red because the irises are clear, and you can see the blood vessels.
- If a person has two different colored irises, then it’s a condition called heterochromia. This can be present at birth or be developed later. That’s why you can see people with one blue eye and green. Or a person with dark brown eyes can have a partially green iris.
- There’s a rare eye disorder called aniridia where the colored part or iris is not present, or it’s only partial. This disorder can be diagnosed at birth or after four weeks, and it typically happens in both eyes. In these cases, you will only see a very dilated pupil.
Race and eye color
To have an approximate idea of what your baby’s eyes will look like, you can analyze the expected behavior based on the parent’s race and ethnicity.
Caucasian babies, no matter from which part of the world they come, have lighter skin and may be born with blue or gray eyes, which will change color in time but have a more significant probability of remaining blue.
Asians and babies with darker skin, even if they’re born with gray or blue eyes (which is rare), are more likely to have dark brown eyes or other brown shades.
However, there are cases where darker skin babies have the blue eye gene, and even if they’re from brown-eyed parents, they may end up having blue eyes. And it’s also common to find Caucasian babies with brown eyes.
Are all babies born with blue eyes?
A common belief is that all babies are born with blue eyes, but this is simply a myth as it’s primarily Caucasian babies born with blue eyes. African, Asian, Hispanic, and some European descendants are typically born with gray or brown eyes.
Babies can be born with blue eyes, gray eyes, or even brown eyes. Once they’re exposed to light, the melanin in the iris is activated, and the eyes change color.
No matter if your baby’s eyes are blue when their born, once the melanin begins to work, they may turn green, hazel, or even brown. The same happens with gray eyes; they will experience color changes.
Melanin darkens the eye color and changes its hue, so babies with blue or gray eyes may end up with brown, green, or hazel eyes or remain blue or gray. Babies born with brown eyes will remain that way. The shade may vary, but they won’t turn lighter.
When to be concerned with eye color changes
Melanin is a brown pigment, so as it develops the iris color, it makes them darker, not lighter. There might be rare cases when they can go lighter. If you notice that your baby’s irises are becoming lighter, even if it’s just one of them or both, you should consult your pediatrician or go directly to an ophthalmologist.
Also, if you notice the baby’s eyes look cloudy with a white, grayish-white, or yellow film in the pupil, get them checked by a specialist.
Although sometimes harmless, these color changes can be red flags that may indicate problems, conditions, or injuries.
Final thoughts
A child’s eyes are beautiful no matter the color they are. And it’s a fun experience to try guessing how much they will change over time.
Seeing how a newborn’s eye color changes during their first year can be fascinating. Light eyes turning a darker shade or guessing if your baby’s blue eyes will stay blue or turn dark blue is an excellent example of how the human body, genetics, and biology combine to make magic happen.
Remember that it is normal for babies’ eyes to change color and that most babies will experience several changes before their first birthday. Newborns’ eyes, whether blue, gray, or brown, can end up anywhere within the color spectrum as they get exposed to more light and melanin gets to work.
Be careful with using baby products that claim they can lighten a baby’s eye color because they can either not do anything or cause damage to your baby’s eyes. There’s no reason to change a baby’s eye color, so consult a medical specialist for more information and guidance before you try anything.