Nail biting (also known as onychophagia) is a common problem (20-30% of the general population) that can persist into adulthood. Usually it is labelled a ‘bad habit’, but it is not always as simple as that, which is why so many people struggle to stop. A psychodermatological approach to breaking the cycle of nail biting can be a way forward.
Why do people bite their nails?
Exactly why people bite their nails is not fully understood. It is however likely to be an interplay of several factors:
Several studies indicate that there is a genetic component to nail biting (also known as onychophagia). One study has shown that 36.8% of nail biters had at least one family member with this habit. Studies of twins have shown that identical twins are more likely to both be nail-biters than non-identical twins.
There has been some suggestion that anxiety is associated with nail biting, but the evidence is not consistent (i.e. some studies show no difference in anxiety disorders between nail-biters versus non nail-biters; but another study has shown that up to 24.2% of nail biters will develop anxiety at some point in their lifetime). Similarly, there has been a noted trend for nail biting among people with obsessive-compulsive disorder (OCD), but this is not proven. Other associated conditions include Tourette syndrome. Childhood psychiatric problems are associated with nail biting (e.g. ADHD, separation anxiety), and nail-biting behaviour has been observed more frequently in children with parents with psychiatric disorders than those without.
Other risk factors that have shown some relation to the development (but not definite cause) of nail biting include low and high birth weight, breast-feeding habits, family conflict, other habitual uses of the mouth (e.g.tooth clenching/grinding), early onset and long duration of bottle-feeding, extensive use of pacifiers/dummies.
Nail-biting behavior is made worse with anxiety, boredom or when concentrating (e.g. working on a difficult task).
How do I identify a trigger?
It is important to be able to able to identify triggers for nail biting, these may include stress, anxiety, or even boredom. To help identify these triggers I suggest keeping a daily journal to write down any thoughts/feelings/situations that promote nail biting (you can write these down in a notebook or even on your mobile phone/laptop/tablet etc.). You may be able to pick up a pattern if you do this, for example ‘I only bite my nails when I am watching TV or bored’. It will then be easier to deal with or stop nail biting. This can be difficult to do on your own, especially if nail-biting is happening largely subconsciously, it may be helpful to enlist someone you trust to make you aware of biting behaviour.
How can I overcome nail biting?
Techniques to overcome nail biting include:
Reprimanding the nail-biting behaviour (‘Stop biting your nails!’) with an aim to stop it is probably more appropriate for children rather than adults! However, in studies, it has not shown to be particularly helpful.
Increasing awareness of nail-biting behaviour, predisposing activities, or warning signs, and instead practicing a distracting behaviour (e.g. clasping hands) may help stop nail biting. Habit reversal works on the principle of recognising the behaviour/habit, in this case nail-biting, and then developing a competing behaviour that is performed instead. It is a form of cognitive behavioural therapy and has shown to stop/reverse nail-biting behaviour.
Manipulation of an object, for example, a stress ball, can also distract from nail biting behaviour and deliver the same satisfaction. This type of treatment has shown to be helpful for nail biting (but not as good as habit reversal).
The practice of applying a bitter tasting lacquer to the nail to deter from nail biting is popular, and a form of aversion therapy. The nail lacquer contains denatonium benzoate and sucrose octaacetate and is available over the counter. This method has shown to improve nail biting.
A wristband or other form of easily visible non-removable reminder can be worn to remind people not to nail bite.
Application of artificial nails or gel manicures
I hear from my patients that this is a popular technique that they have used with positive results. The obstacle to nail biting is not wanting to ruin their nice new nails/nail paint!
This is only suitable for moderate to severe cases, or in those patients who are developing complications or poor quality of life. Medication can be used in addition to any of the options above. It requires specialist referral to a psychodermatologist or psychiatrist.
Importantly, if nail biting is a sign of another underlying problem, it is unlikely to respond to standard treatment until that problem is addressed (e.g. psychiatric or psychological problem, behavioural disorders).
www.skinsupport.org.uk (set up by the British Association of Dermatologists)
https://www.bfrb.org/ (The TLC foundation for body-focused repetitive behaviours)
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- Bakwin H., Bakwin R.M. Saunders; Philadelphia: 1972. Behavior disorders in children; pp. 306–510.
- Friman PC, Larzelere R, Finney JW. Exploring the relationship between thumb-sucking and psychopathology. J Pediatr Psychol. 1994;19:431–41.
- Ghanizadeh A. Association of nail biting and psychiatric disorders in children and their parents in a psychiatrically referred sample of children. Child Adolesc Psychiatry Ment Health. 2008;2:13.
- Ghanizadeh A. ADHD, bruxism and psychiatric disorders: does bruxism increase the chance of a comorbid psychiatric disorder in children with ADHD and their parents? Sleep Breath. 2008;12:375–80.
- Ghanizadeh A., Derakhshan N., Berk M. N-acetylcysteine versus placebo for treating nail biting, a double blind randomized placebo controlled clinical trial. Antiinflamm Antiallergy Agents Med Chem. 2013;12(3):223–228.
- Joubert CE. Relationship of self-esteem, manifest anxiety, and obsessive-compulsiveness to personal habits. Psychol Rep. 1993;73:579–583.
- Klatte KM, Deardorff PA. Nail-biting and manifest anxiety of adults. Psychol Rep. 1981;48:82.
- Leonard HL, Lenane MC, Swedo SE, Rettew DC, Rapoport JL. A double-blind comparison of clomipramine and desipramine treatment of severe onychophagia (nail biting) Arch Gen Psychiatry. 1991;48:821–7.
- Ooki S. Genetic and environmental influences on finger-sucking and nail-biting in Japanese twin children. Twin Res Hum Genet. 2005;8(4):320–327.
- Pacan P, Grzesiak M, Reich A, Szepietowski JC. Onychophagia as a spectrum of obsessive-compulsive disorder. Acta Derm Venereol. 2009;89:278–80.
- Ronen T, Rosenbaum M. Helping Children to Help Themselves: A Case Study of Enuresis and Nail Biting. Research on Social Work Practice. 2001;11:338–56.
- Sabuncuoglu O., Orengul C., Bikmazer A., Kaynar S.Y. Breastfeeding and parafunctional oral habits in children with and without attention-deficit/hyperactivity disorder. Breastfeed Med. 2014;9(5):244–250.
- Silber KP, Haynes CE. Treating nailbiting: a comparative analysis of mild aversion and competing response therapies. Behav Res Ther. 1992;30:15–22.
- Tanaka O.M., Vitral R.W., Tanaka G.Y., Guerrero A.P., Camargo E.S. Nail biting, or onychophagia: A special habit. Am J Orthod Dentofacial Orthop. 2008;134(2):305–308.
- Teng EJ, Woods DW, Marcks BA, Twohig MP. Body-focused repetitive behaviors: The proximal and distal effects of affective variables on behavioral expression. Journal of Psychopathology and Behavioral Assessment. 2004;26:55–64.
- Turgeon-O’Brien H., Lachapelle D., Gagnon P.F., Larocque I., Maheu-Robert L.F. Nutritive and nonnutritive sucking habits: A review. ASDC J Dent Child. 1996;63(5):321–327.
- Vafaei B, seidy A. A comparative study on the prevalence of emotional and behavioral symptoms in children and adolescents born to mothers with schizopherenia and other psychotic disorders. Acta Medica Iranica. 2003;41:254–9.
- Velazquez L, Ward-Chene L, Loosigian SR. Fluoxetine in the treatment of self-mutilating behavior. J Am Acad Child Adolesc Psychiatry. 2000;39:812–4.
- Woods D.W., Murray L.K., Fuqua R.W., Seif T.A., Boyer L.J., Siah A. Comparing the effectiveness of similar and dissimilar competing responses in evaluating the habit reversal treatment for oral-digital habits in children. J Behav Ther Exp Psychiatry. 1999;30:289–300.