Because long eyelashes are aesthetically pleasing and seen as a desirable trait that adds to physical attractiveness, some people seek to enhance their eyelash length artificially, by means of eyelash extensions, false lashes attached to the eyelid, cosmetics, or growth products. Additionally, eyelashes which are curled are also more prominent, being able to better display their length especially when viewed from the front. The enhanced appearance of curled eyelashes can be cosmetically achieved by use of eyelash curlers, or eyelash perms. However, these methods do not physically lengthen the lashes.

An external hordeolum, or stye, is a purulent inflammation of infected eyelash follicles and surrounding sebaceous ( Gland of Zeis) and apocrine ( Moll's gland) glands of the lid margin. Latisse was introduced in the first quarter of 2009 by Allergan as the first drug to receive FDA approval for eyelash growth. Latisse is a solution of bimatoprost, a prostaglandin analog and the active component of the glaucoma medication Lumigan. According to Allergan, noticeable eyelash growth occurs within 16 weeks. Growth is reported to occur primarily on the upper eyelashes, with as much as a 25% increase in length. [30] In addition, the past decade has seen the rapid increase in the development of eyelash conditioners. These conditioners are designed to increase the health and length of lashes. Many utilize seed extract, minerals, and other chemicals to achieve these results. [31]Eyelash length is closely linked to the width of the eye, with the lashes typically growing to one-third the width of the eye as an evolutionary adaptation to reduce tear film evaporation and dust deposition. Lashes longer or shorter than one-third the width of the eye have been shown to have reduced efficacy in serving their function. [4] The typical width of the human eye is 24.2 mm, [14] resulting in the average human eyelash length of 7 to 8 mm. This evolutionary trait is perhaps why lashes in humans rarely grow beyond 10 mm in length. [11] The length of eyelashes in humans vary greatly by individual, but not by sex or ethnicity. Short eyelashes are shown in this female subject Demodex folliculorum (or the demodicid) is a small mite that lives harmlessly in eyelash and other hair follicles, and about 20% of people have these mites living on them. [16] Occasionally they may cause blepharitis. Plug and sew eyelashes for women". Xinhua News. 25 October 2006. Archived from the original on 18 February 2014 . Retrieved 16 March 2013. Ancient Romans considered long eyelashes a component of aesthetically ideal eyes. Pliny the Elder wrote that eyelashes fell out from sexual excess, so women desired long lashes as a symbol of chastity. [24] This may have had medical basis as a symptom of syphilis is often alopecia of the lashes, [25] suggesting that individuals with short or sparse lashes were sexually promiscuous.

Adam, Aimee (October 2021). "Beauty is in the eye of the beautiful: Enhanced eyelashes increase perceived health and attractiveness". Evolutionary Behavioral Sciences. 15 (4): 356–367. doi: 10.1037/ebs0000192. ISSN 2330-2933. S2CID 214292834.

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Permanent eyelash tints and eyelash extensions have also become popular procedures, even in fairly basic salons. It is also possible to get eyelash transplants, which are similar in nature to hair transplantation often done on the head. Since the hair is transplanted from the hair on the head, the new eyelashes will continue to grow like head hair and will need to be trimmed regularly. [29] Because of the role long lashes play in contributing to overall facial attractiveness, they are a prized and desired trait. A study found that a group of Japanese women in their 20s and 30s desired upper eyelashes as long as 14.1 mm, a length outside the range of typical human lash lengths and over twice longer than the average length of 6.8 mm of the same population. [23]