Why Do Children Bite Nails And How To Stop Them From Biting?

Image: iStock


Nail-biting (NB) or onychophagia is a prevalent problem that involves biting the cuticle, soft tissue, and the nail itself. It is a common stress-relieving behavior in school-aged children and adolescents, with the prevalence decreasing with age (1) (2).

Boys are more likely to continue NB throughout adolescence (particularly after ten years), but gender does not influence its prevalence in childhood (3). Although it is a seemingly harmless behavior, chronic NB can lead to nail and oral cavity complications.

Read this post to know the causes of NB, its prevalence, and how to get kids to stop biting nails.

Why Do Kids Bite Their Nails?

The exact cause of NB in children is unknown. Studies reveal that it can be caused by various factors, including behavioral challenges, genetic factors, and underlying psychiatric illnesses such as follows (1):

  • As a stress reliever or a strategy to cope with intense feelings and anxiety
  • May pick up the habit in times of boredom or inactivity or while engrossed in activities such as watching television or reading.
  • May pick up the habit without any apparent cause like other body-focused repetitive behaviors (BFRB), such as hair twisting, skin pricking, or thumb sucking.
  • Long-term bottle-feeding, combined with pacifier use, may cause NB behaviors in children as a pathologic continuation of their suckling reflex in infancy (4).

Some studies also claim that NB in children may appear as a co-morbidity with certain psychiatric disorders, including (5)

  • Attention deficit hyperactivity disorder (ADHD)
  • Oppositional defiant disorder (ODD)
  • Separation anxiety disorder is directly associated with NB in children, as shown in various studies.
  • Tic disorder
  • Tourette syndrome
  • Mental retardation
  • Pervasive developmental disorder

A study also shows an association between psychiatric problems, such as major depressive disorder, schizophrenia, and bipolar disorder, in parents and NB in their children. Further, genetic studies show that a family history of NB in both parents predisposes a child to a three- or four-fold risk of developing this condition (4).

When Does Nail-Biting Become Worrisome?

NB is a harmless and self-limiting behavior that typically does not require intervention in most children (6). However, chronic compulsive NB may induce severe complications and facilitate the seeding and transfer of fomites between the oral cavity and fingers. These complications may include (2) (3) (4)

  • Clinical dental crowding, rotations, or malocclusion (particularly of the anterior teeth)
  • Chipped and notched teeth with inflamed gingiva
  • Biting pressure-induced fractures at the incisor margins, apical root resorption, alveolar destruction, or gingivitis
  • Irreversible shortening of fingernails with deterioration of the nail beds, preventing normal nail growth
  • Gum injury
  • Temporomandibular disorder
  • In rare cases, NB may cause finger infections by damaging the nail tissues (paronychia).
  • Parasitic intestinal infections, bacterial infections (change of the oral carriage of Enterobacteriaceae), and tooth root damage

NB may be a difficult habit to break; hence, to avoid nail and oral infections while your child indulges in the habit, ensure they maintain nail hygiene (4).

How To Stop A Child From Biting Nails?

The treatment of NB in children involves a multidisciplinary approach and depends on the condition’s severity (determined by the associated complications) and related risk factors (6).

Parental involvement is the first line of treatment of NB in children. Hence, your child’s doctor may suggest some of the following techniques to help your child stop biting their nails (7) (8):

  • Aversive therapies, including keeping the nails trimmed or applying bitter nail polish, may help. However, bitter nail paints are contraindicated in children as they may consider it a punishment.
  • Substitute NB with other relaxation techniques, such as taking deep, slow breaths
  • Identify the triggers that are causing NB.
  • Keep your child busy and focused on other things.
  • Avoid punishing or nagging your child as it may worsen the condition. Instead, encourage your child and give them support and confidence.

You may also seek professional advice if there is no improvement in your child’s condition. The treatment methods for NB in children include (4):

  • Psychotherapy, including cognitive-behavioral therapy, teaches techniques to control NB behaviors in children.
  • Functional analysis therapy can be effective if NB is habitual.
  • Habit reversal therapy (HRT) comprises self-awareness training, replacement of NB with other behaviors, and supporting the child.
  • Pharmacotherapeutic management with a selective serotonin reuptake inhibitor (SSRI), such as Fluoxetine or N-acetylcysteine

NB is a common habit for relieving stress in children and adolescents. It may be caused by various factors, including behavioral challenges, genetic factors, and underlying psychiatric disorders. Though generally a self-limiting condition, chronic compulsive NB may induce nail and oral cavity complications. If your child’s NB habit seems worrisome, consult your pediatrician for the right management techniques.


MomJunction's articles are written after analyzing the research works of expert authors and institutions. Our references consist of resources established by authorities in their respective fields. You can learn more about the authenticity of the information we present in our editorial policy.
  1. Nail-Biting.
  2. Yunhye Oh et al.; (2020); Defining Subtypes in Children with Nail Biting: A Latent Profile Analysis of Personality.
  3. Ahmad Ghanizadeh and Hajar Shekoohi; (2011); Prevalence of nail biting and its association with mental health in a community sample of children.
  4. Mohsen Baghchechi et al.; (2021); Art of Prevention: The importance of tackling the nail-biting habit.
  5. Ahmad Ghanizadeh; (2011); Nail Biting: Etiology, Consequences and Management.
  6. Eric D Hodges et al.; (1994); Nail-biting and foreign body embedment: a review and case report.
  7. How To Stop Biting Your Nails.
  8. Nail Biting Prevention and Habit Reversal Tips: How to Get Your Child to Stop.
The following two tabs change content below.

Reshmi Das

Reshmi Das has over three years of experience as a clinical coordinator, medical content writer and medical conference coordinator. Her continuous interest in medical journals and writing makes her write well-researched articles for MomJunction. She writes health and wellness articles for children and pregnant and lactating women. Reshmi has completed her Master’s degree in Biotechnology. She is currently pursuing an Executive... more