Eyelashes play an important role in protecting our eyes from dust and debris. They also help regulate the amount of light entering our eyes. So why is it that some people are born without eyelashes or lose them later in life?
What are eyelashes?
Eyelashes are short, curved hairs that grow from the edges of the upper and lower eyelids. The hairs originate from hair follicles at the eyelid margin. Eyelash follicles contain arrector pili muscles that allow the hairs to stand upright to prevent particles from entering the eye.
Humans have between 150-200 lashes on the upper lid and 50-100 lashes on the lower lid. The upper lashes are usually more numerous and longer than the lower lashes. Eyelash length ranges from 8-12 mm long. The lashes grow in three rows along the lid margin and help protect the eye from dust, debris, and sweat.
Functions of eyelashes
Eyelashes serve several important functions:
- Protect the eyes – Eyelashes help keep foreign particles like dust, dirt, and debris from entering and irritating the eye. They filter particles before they can get into the eye.
- Reduce glare – The eyelashes diffuse bright light entering the eye to reduce glare. This improves visual clarity in bright conditions.
- Spread tears across the eye – Eyelashes catch tears from the lacrimal gland and spread them across the surface of the eye to moisturize and lubricate it.
- Communicate nonverbally – Long, fluttering eyelashes are considered attractive in many cultures. Batting the eyelashes can communicate flirtation and charm.
Without eyelashes, our eyes would be much more prone to irritation, infection, and damage from external particles. Eyelashes are an important protective feature of the eyes.
Causes of missing eyelashes
There are several possible causes of missing or absent eyelashes:
Genetics
Some people are born without eyelashes due to genetic factors. An extremely rare congenital condition called congenital distichiasis can cause a complete lack of eyelashes at birth. Other genetic disorders like ectodermal dysplasia can also cause missing eyelashes.
Medical conditions
Certain medical conditions and hormonal changes can cause eyelash loss:
- Alopecia areata – An autoimmune condition that causes hair loss on the scalp, face, and body. It can result in complete loss of eyelashes.
- Blepharitis – Eyelid inflammation that damages the hair follicles.
- Thyroid disorders – Both hyperthyroidism and hypothyroidism can lead to eyelash thinning and shedding.
- Trichotillomania – A disorder that causes people to compulsively pull out their own eyelashes.
- Chemotherapy – Chemotherapy drugs damage rapidly dividing cells like hair follicles, causing eyelash loss.
- Aging – As we age, eyelash follicles may produce thinner, shorter hairs leading to sparse eyelashes.
Infections
Infections of the eyelid margin can cause inflammation, scarring, and permanent damage to the eyelash follicles. Examples include:
- Demodex – Microscopic mites that infest eyelash follicles.
- Bacterial infection – Staphylococcus aureus is a common culprit.
- Seborrheic dermatitis – Can cause eyelid inflammation, scaling, and eyelash loss if left untreated.
Trauma
Injury to the eyelids through surgery, burns, or other trauma can damage eyelash follicles and prevent regrowth. Examples include:
- Eyelid surgery like blepharoplasty can sometimes cut follicles or alter lid anatomy.
- Chemical burns from cleaning solutions or makeup remover can damage follicles.
- Physical injuries like dog scratches can remove entire eyelashes.
Toxic or irritant exposure
Frequent use of certain cosmetic products can irritate eyelids and damage follicles, causing eyelash loss:
- Mascara and eyeliner – Preservatives like parabens or thimerosal can irritate.
- Eyelash curlers – Applying too much heat or pressure can pull out lashes.
- False lashes or lash extensions – Can damage natural lashes if applied improperly.
- Eyelash perm chemicals – Perm solutions can burn and irritate lash follicles.
Disorders featuring missing eyelashes
There are a few syndromes and rare diseases linked to absent or reduced eyelashes:
Ankyloblepharon-ectodermal defects-cleft lip/palate (AEC)
AEC syndrome is a rare congenital disorder characterized by severe scarring and fusion between the eyelids (ankyloblepharon), missing eyelashes, and developmental defects of the skin, nails, teeth, and palate. The ectodermal dysplasia disrupts development of ectoderm-derived structures like hair, nails, teeth, and skin.
Blepharophimosis syndrome (BPES)
An inherited disorder characterized by shortened eyelid fissures (blepharophimosis), droopy eyelids (ptosis), and absent eyelashes (hypotrichosis). In some cases of BPES, premature ovarian failure also occurs. Mutations in the FOXL2 gene cause defects in eyelid and eyelash formation.
Congenital distichiasis
This very rare condition present from birth is characterized by double rows of eyelashes arising from the meibomian glands along the eyelid margin. Often the extra eyelashes are sparse, short, and grow abnormally pointing inward toward the eye (distichiasis). In severe cases, patients may have a complete absence of normal eyelashes.
Ectodermal dysplasia
Ectodermal dysplasia is not a single disorder but a group of over 150 inherited conditions affecting hair, nail, skin, sweat gland, and tooth development. Some forms lead to abnormal formation of eyelashes and even complete absence of lashes.
Diagnosing the underlying cause
It’s important to have chronic eyelash loss evaluated by an ophthalmologist or dermatologist to determine the root cause. The doctor will review your medical history and perform a detailed eye exam. Tests may include:
- Blood tests to check for hormonal abnormalities related to thyroid, pituitary gland, or ovaries
- Slit lamp exam of the eyelids to look for signs of infection or inflammation
- Skin biopsy to check for immune-related hair loss disorders
- Genetic testing if a inherited disorder is suspected
Identifying the precise reason for missing eyelashes is key for getting proper treatment to restore lashes or prevent further loss.
Treatment options for absent eyelashes
Treatment depends on the underlying cause of missing eyelashes. Some options include:
- Medications – Steroids, immunosuppressants, or antifungals to treat autoimmune or infectious causes.
- Hormone replacement – Thyroid hormones or androgens can help some cases of hormone-related loss.
- Surgery – Eyelid surgery to correct droopy lids or altered eyelid anatomy that prevents lash growth.
- Prosthetics – Artificial eyelashes can be attached for cosmetic purposes.
- Eyelash treatments – Prescription serums like bimatoprost to stimulate lash regrowth.
In cases of permanent damage to eyelash follicles, options are more limited but cosmetic procedures can create the appearance of eyelashes.
Coping with absent eyelashes
It can be emotionally difficult to lose your eyelashes or be born without them. Here are some tips for coping:
- Use lubricating eyedrops to prevent dry eyes or irritation.
- Wear sunglasses outdoors to reduce dust/glare getting in your eyes.
- Consider eyelid tattooing to create the look of eyeliner.
- Talk to loved ones about what you’re going through.
- Connect with support groups of others with similar conditions.
- Work with your doctor to control the underlying cause.
- Focus on inner strengths and qualities besides your appearance.
Researchers are also working on regenerative medicine approaches to regrow eyelashes by activating follicle stem cells in the eyelids.
Conclusion
Absent or missing eyelashes can arise from congenital conditions, underlying diseases, hormonal changes, infections, injuries, and other causes. Identifying the root cause is important to guide treatment. While options exist to replace or regrow eyelashes in some cases, other times the loss may be permanent. Working closely with your eye doctor and being patient with treatment are key to managing eyelash loss.