Pica: what this disorder is and when to seek help

What is pica?

Pica describes the persistent ingestion of substances that are not food and provide no nutrients. Clinical criteria include behaviour lasting at least one month and being inappropriate to the person’s developmental level, according to the Merck Manual. They also check that it is not part of an accepted cultural practice [1]. A single episode is not enough to apply a label.

Assessment considers other conditions and whether the behaviour needs specific attention [1]. It is helpful to say exactly what was ingested and when, rather than trying to work out a diagnosis at home. Pica is not defined by concern about weight or body image, although it can coexist with other eating difficulties. Our general eating disorders guide explains other eating disorders.

If ingestion of something that is not food happens repeatedly, the first step is to find out what happened and assess the risk.

What signs go beyond one-off curiosity?

Repetition matters more than a striking incident. It is worth seeking advice when ingestion happens again, continues over time or is difficult to prevent. Also mention any pain, constipation, vomiting or changes in eating. Ingesting certain substances can cause poisoning, infection or intestinal obstruction [1].

Do not wait for symptoms if the substance could be toxic or cause an obstruction [1]. Having no discomfort at first does not rule out risk.

The useful questions are whether the behaviour is continuing and what material the person may have ingested. Keeping that material out of reach may reduce the risk of it happening again, but does not replace assessment. If the person is a minor, avoid blame and ask their paediatrician for help; information from caregivers is valuable for understanding the situation.

When is it part of child development?

In early childhood, putting objects in the mouth is part of exploration. Pica is not diagnosed in children under two on the basis of this behaviour alone [1]. Age, persistence and what was actually ingested all affect the assessment.

If the behaviour happens repeatedly, talk to the child’s paediatrician. They can review development and nutritional status and decide whether other professionals are needed. If your concern is about eating in general, the guide to child nutrition may help.

For an older child, too, seeing them put things in their mouth is not enough by itself. The paediatrician distinguishes exploration from persistent behaviour and other possible problems. Do not wait a month to ask for advice if there is physical risk: the time period is a diagnostic criterion, not a reason to wait.

Who can it affect?

Pica can occur at different stages of life. It has been described during pregnancy and alongside iron-deficiency anaemia; the causal relationship is not clear [1]. It is not limited to one age or one condition.

A US CDC study included more than 4,700 children aged two to five. It found pica in 23% of those with autism and 8% of those with other developmental difficulties, compared with 3.5% of the remaining children [2]. This is an association in the population studied, not a test for identifying an individual. Someone without those conditions may also need assessment.

If the behaviour occurs during pregnancy, tell your healthcare team. They can assess the safety of what was ingested and check for a deficiency [1]. If it occurs alongside a developmental condition, care should be adapted to the person’s communication and needs [1].

What role does nutrition play?

Nutritional assessment helps identify deficiencies and review whether the behaviour has reduced the person’s usual food intake. A systematic review of 89 studies, published in BMC Oral Health, found a strong association between pica and anaemia or iron deficiency [3]. This association does not prove that a deficiency explains every case or that changing the diet is enough.

A doctor may request tests depending on the history and the material ingested [1]. If they identify an iron or zinc deficiency, they decide how to treat it and monitor the response. In consultations, we can support eating when the team identifies a nutritional need. We never suggest a plan as a substitute for medical and psychological assessment.

Nor should a normal blood test be assumed to rule out risk. Complications depend on what was ingested and on symptoms [1]. There may have been an exposure requiring further examination even if the person is eating enough. It is helpful to discuss nutrition once immediate safety has been clarified.

How is pica treated?

The first point of contact is usually a GP or paediatrician, depending on age. The professional asks about the behaviour, development and possible exposures. They assess complications, nutritional status and which tests make sense in that situation [1].

A specialist psychologist or a team experienced in child development may then be involved. Behavioural support is tailored to what triggers or maintains the behaviour and to the person’s environment. In a series of 33 cases published in the Journal of Applied Behavior Analysis, an individualised behavioural treatment reduced pica by at least 90% in 30 of them [4]. It is designed and delivered by a specialist team.

Coordination matters: Medicine addresses safety and possible deficiencies; Psychology or developmental specialists work on the behaviour. Nutrition is involved when there is an eating or nutritional issue to address. The plan is tailored to age and to what the team observes, involving the person and their caregivers when appropriate.

What we see in consultations

A common question is whether “eating better” is enough. If there is anaemia, it needs to be treated. But looking only at the plate leaves the behaviour and possible harm from what was ingested unexamined.

Another question is whether to wait until there is certainty that it is happening repeatedly. There is no need to wait: sharing what is happening early helps arrange an assessment without judgement. You do not need to guess the name of the problem before asking for help.

We also see concern about explaining the behaviour to family members or professionals. You can simply say what you have noticed, without attributing motives or assigning blame. For minors or people who need support, those living with them can provide useful details. The aim is to protect and understand, never to blame someone.

How to prepare for the first assessment

Write down what happened, when and how often you have noticed it. If you know what material was ingested, tell the healthcare professional. Describe digestive symptoms, appetite changes and relevant history. This information helps decide whether tests or a referral are needed [1].

If you can, explain what was happening before and after each episode without interpreting the person’s intention. For a minor or someone with communication difficulties, this context can guide later support. Also share what protective steps have already been taken. Do not delay the appointment to compile a perfect record.

If the person is pregnant, a young child or has another health condition, mention this when booking the appointment. This helps the team prioritise and coordinate the assessment.