Thumb sucking and Nail Biting

by NM
(Mumbai, India)

Dear Doctor, My 8 years old son still sucks his thumb and has the habit of biting his nails. Whenever he is free his thumb goes into his mouth or he is biting nails.

He is performing very well in school. The feedback from teachers is all positive. He is a very active child.

Wondering what the reason could be for nail biting and thumb sucking habits!
Could it be fear, loneliness or a manifestation of some sort of deficiency in his body-say, vitamins?
Please let me know your thoughts on this.
Regards, NM

The Expert, Ren Chats, Answers -

Thumb Sucking

The inborn sucking reflex develops during the intrauterine life and facilitates breastfeeding during infancy. The reflex sucking disappears at about 4 months of age.

The action of rhythmic sucking has security and self-soothing effects. That explains why the dummy soothers are so popular.

However, unlike sucking reflex, thumb sucking is not an inborn pattern of behavior. Infants use its calming effect to fight their frustration. Consequently, thumb sucking often continues through the childhood, with an incidence of about 25 % in under 2 years and 15% under 5 years.

Thumb sucking is a socially accepted among infants and toddlers. The professionals discourage parents to prevent thumb sucking in children up to 3 years of age. By the age of 5, most children are able to overcome their desire to suck their thumb in face of social, behavioral and developmental demands. The older children, who continue to suck their thumb, either do so out of habit or have reasons to be frustrated.

How can I help my child overcome this habit disorder?

1. Pretend to ignore the action

2. Educate the child on the ill effects of thumb sucking like:

a) Fingers carry germs.

b) While sucking, person breaths through mouth which aggravates the chances of repeated sore throats during early childhood.

c) Becomes prone to peer-teasing.

d) Not an accepted norm of the society for the age.

e) Jaw pain.

f) Inflammation at the angles of the mouth - often mistaken for vitamin B deficiency.

g) Development of chronic paronychia -infection of the nail folds.

h) Spoils looks due to teeth and jaw changes.

3. Look out for precipitating factor and try to resolve it.

a) Boredom and loneliness creeps in when parents get busy with household chores and the child is left alone with TV or studies. But the child, who has waited almost all day long for parents’ company, finds himself in an emotional vacuum. Thumb sucking/nail biting then becomes his way to sooth himself to meet the expected behavior.

b) Meal time discipline or disinterest in eating.

c) TV programs often make children anxious for many reason. They develop their role models from them and set unreachable goals for themselves.

d) Homework and demanding school studies.

e) Bedtime phobias.

4. Behavior therapy.

a) Help the child to relax. Take it easy policy should be adopted by the parents and the teachers in order to motivate children meet the set goals in an easy-going manner.

b) Divert child’s attention towards something more interesting when you notice him sucking his thumb. This will help attain a state of increased calmness and reduce anxiety, stress or anger.

c) Praise the child when he does not suck his thumb.
Simple reinforcement with small gifts, like a star or his favorite sticker for each block of time that he does not indulge into thumb sucking will help.

d) Introduce self-monitoring.
That is let the child maintain the record of time blocks when he did not give in to his urge for thumb sucking. This acts as a gentle reminder and gives the child a feeling of achievement.

5. Noxious agents like bitters, are rarely used.

The stringent taste acts as a reminder and enforces self-regulation. It is an effective way to control impulsive thumb sucking, when used with a gentle gesture and not as a tool of punishment. But if you plan to introduce noxious agent, it should be done with full informed consent of the child. Child should not take it as a form of punishment, or else the purpose will be lost.

Negative practices like scolding, using harsh words, teasing and punishment are traumatizing to child’s self-esteem, and may even perpetuate the habit in-stead of getting rid of it.

Conditions that would warrant medical intervention:

1. Defective teeth alignment.

2. Flaring of front teeth of the upper jaw (maxillary incisors erupt between 7-8 years), an open bite and posterior cross bite may need dental intervention.

3. Resistant cases: Parental support usually helps children to overcome thumb sucking. However, in small percentage of cases, it may progresses well into teens, who commonly resist parental corrections. Though the underlying cause could be habit formation, it is best to have medical consultation for them to rule out impulse control disorders, psychological disturbances and stereotype movement disorder.


Nail Biting (Onychophagia)

Nail biting is a bad habit, which is notoriously difficult to break. It is a widespread problem of the growing years. The incidence among tweens (usually between 8-12 years of age) is noted to be as high as 33%. Children often do not even notice when they are biting their nails. They just do it along with their routine day to day actions.

How does the habit of nail biting evolve?

Nail-biting is often stress-induced, but certainly not at the onset. At the onset, children take up nail biting just as a gesture that they have liked in someone else. Most children bite their nails while watching television, reading, socializing, or even while talking. Later it develops into a habit and has no particular trigger attached to it. Eventually, these children start biting their nails each time they face a stressful situations. Therefore, it is generally interpreted as a sign of nervousness and lack of confidence..

The habit acquired innocently during early childhood frequently tracks its way into teens. Teenagers, on their way to adulthood, travel through a tortuous emotional path. It is then, that nail biting habit develops in to a clinically recognized disorder, medically known as Onychophagia.

Nail biting is commonly seen in children of anxious personality. Periods of physical inactivity, boredom, stress or even excitement arouses in them an uncontrollable urge of nail biting. They keep chewing the nails despite the injuries they sustain. Consequently, these children usually have exceedingly short nails and torn nail fold cuticles.

This extreme form of nail biting is the outward manifestation of anxiety in children. It is also considered a form of motor discharge of inner tension and it is classified as an impulse control disorder. Presence of bitten short nails with torn nail folds should alert parents and teachers of the possibility of emotional imbalance in the child. Early intervention will prevent the anxiety associated oncoming teenage depression.

In recent years, nail biting is so commonly seen, that it is thought provoking –
Is our society laying unrealistic demands on children?
Are children being exposed to information overload too early in life?
Is it due to over exposure to electromagnetic energy, generated by increasingly used electronic gadgets in modern communication and entertainment system? – even toys are electronic!

Causes of anxiety in children:

1. Unhappy social situations:

a. Competitive school curriculum

b. Effort to meet high expectations of the parents and society

c. High set goals for self

d. Having problems at school

e. Peer disputes

f. Unhappy home

2. Working parents are often too busy in the evenings meeting the daily chores. In this situation, it is best to involve children in the chores so that parents-child interaction continues and the children do not feel left out and lonely.

3. Depression and anxiety often co-exist. They manifest much later, during teenage when the stresses increases.

To help children overcome nail biting habit disorder – follow the same guidelines as noted above under “Thumb Sucking”.

Comments for Thumb sucking and Nail Biting

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Mar 10, 2020
Anxiety as a cause of Nail Biting
by: Renuka Anup

I am truly grateful for your valuable feedback. Admire your observation and determination to help those who would be searching for the answer to this nagging problem - a social embarrassment.
I have now added some links to the relevant pages.
Unfortunately, you have posted as anonymous, yet my thanks are to you personally.
Thanks a million.
Your suggestions are most welcome. They help me give better information to our readers.

Dec 23, 2019
Caused by anxiety
by: Anonymous

Thank you for addressing causes as opposed to the many articles that merely mentioned the possibility of reducing allergies. As a nail biter into my 30s and thumbsucker until I was 17, I can speak to anxiety as a cause. Although most children will not face this extreme challenge, anxiety could still be their trigger. One source you do not list is conflict or tension inside one’s own home such as dealing with alcoholism, abuse or sibling rivalry. The key is to help children find access to resources (not to convince the adults that they are the problem.
Alternate self soothing techniques can be learned. If more people were enlightened as to the nature of the problem then the solution would be more readily available. Thank you for your attention to this topic.

May 16, 2012
Often ignored, but can lead to major consequences
by: Ren Chats

Thank you NM.

I am sure this will help many children.

Though it is a long answer, do read every word carefully. All facets of the problem need to be understood for effective management.

If you have anymore questions on the subject, post them here as comments, so the link continues.

My best wishes for your son.

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