What is failure to thrive?

Infants and young babies grow and develop very quickly. The average newborn doubles its birth weight within 4-6 months and triples it by the time they are one year old. A one-year-old baby is also 1.5 times longer than at birth.

Different babies have different growth rates and different growth patterns. It is perfectly normal for a baby or young child to have certain periods in which they do not grow or gain weight. 'Failure to thrive' (FTT) is when a child falls consistently behind the weight gain and growth rates expected for their age and gender.

Growth chart.An estimated weight-gain chart for boys. 

FTT is an umbrella term covering many different situations and causes. It is usually diagnosed in children under two years of age. The core problem for all of them is that the child's body is not receiving, or not using, the nutrition it needs. If left untreated, this can cause long-term problems to the child's future development and health.

It is difficult to know exactly how common this condition is, because it does not have a standard definition. It is a common cause for admission of children under two years of age to hospitals in both developed and developing countries.

Treatment of FTT depends on its specific cause or causes and can include both straightforward medical interventions and addressing the child's home and family life.


Children can fail to thrive for many reasons. They can roughly be divided into three categories:

Medical causes

In less than 10% of cases, FTT can be the result of several underlying medical conditions. These problems prevent the child's body from using the food it is receiving in order to grow and develop. These can include:

  • Genetic conditions (such as defects in the digestive system, metabolic conditions, cystic fibrosis, coeliac disease or diabetes) that make it hard for the body to process food and absorb nutrients;
  • Problems with food intake, such as cleft lip and palate, diarrhea or vomiting, that make it hard for the child to eat enough food or retain what was eaten;
  • Allergies to food milk proteins or other components of food;
  • Premature birth, low birth weight, pregnancy complications, or;
  • Conditions that cause the child's body to expend much more energy than usual, for example, some heart and respiratory problems, hormone disorders, nervous system disorders and infections.

Environmental causes

In many cases, FTT is caused by the child not being fed adequately. Causes can include:

  • Poverty, homelessness;
  • Parents or carers do not understand their child's nutritional needs;
  • Lack of structure in family feeding habits, such as no set mealtimes;
  • Parental inattention, parental inexperience, parental neglect;
  • Misdirected parental distress with the child's feeding. For example, anxiety over feeding, worries that the baby is 'too fat', unnecessary dietary restriction, perceived food allergies;
  • For infants and babies, problems with breastfeeding, or;
  • Maternal depression.

Behavioral causes

FTT can also be the result of a child who is not eating well despite being offered enough food. Causes can include:

Food refusal.Food refusal may be one of the causes of failure to thrive. 

Multiple causes

FTT can often be the result of the combination of several of the causes listed above. For instance, the parents of a child who vomits regularly with every feeding might not be inclined to feed it as much, or as often as they normally would. Parental emotional distress can be both a cause of a child's failure to thrive as well as a result of it.


A metabolic disorder that is caused by problems with insulin secretion and regulation and which is characterized by high blood sugar levels. Also known as diabetes mellitus.

Nervous system

The extensive network of cells and structures that is responsible for activating and coordinating the body's functions, sensory input and cognition.


Relating to respiration, the process of inhaling and exhaling air.

Atalay A. and McCord M. (2012) Characteristics of failure to thrive in a referral population implications for treatment. Clinical Pediatrics 51:219–225.

Signs and symptoms

FTT does not have a single definition. FTT is suspected if:

  • The child's weight, length and/or head circumference are at the extreme low end of the standard growth figures for their age, or;
  • The child is growing very slowly or not at all.

Other signs that a child may be failing to thrive include:

In many cases, it will be hard for a parent to notice that their child is failing to thrive, since this can be a gradual process.

Atalay A. and McCord M. (2012) Characteristics of failure to thrive in a referral population implications for treatment. Clinical Pediatrics 51:219–225.

Methods for diagnosis

A doctor will diagnose FTT based on two main methods:

  • A physical examination that includes measurements of height, weight and head circumference, and;
  • A detailed history and an account of the child's and the family's eating patterns.

Further testing may be required if the doctor suspects that an underlying medical condition is causing the child's FTT.

It should be remembered that there are children whose growth and development are at the low end of the standard charts, who are nevertheless healthy and do not have FTT.

Atalay A. and McCord M. (2012) Characteristics of failure to thrive in a referral population implications for treatment. Clinical Pediatrics 51:219–225.

Types of treatment

Treatment of FTT depends on its root cause. For medical disorders, diet must come together with the appropriate medical care.

For environmental causes, it is often best to educate and work with the parents to make it easier for them to provide a good diet for their child. Parents may benefit from consultations with healthcare professionals including dietitians, maternal and child health nurses, social workers and psychologists.

In cases of extreme malnutrition, a child may be admitted to a hospital to receive emergency care and tube feeding.

Nutritional therapy

Nutritional therapy, also known as nutritional rehabilitation, is often used to help children with FTT to 'catch up' - to gain weight more rapidly in a safe and healthy way. An individual plan will be developed by a healthcare professional that includes foods high in calories and nutritional value. This 'boost' of nutrition is usually at about 110% to 120% of normal food intake.

Tube feeding

Tube feeding is used to provide nutrition to patients who cannot obtain adequate nutrition by mouth. Food is delivered straight to the stomach via a feeding tube, which can be inserted into the stomach via an incision in the abdomen, or non-surgically through the nose.


A professional specializing in mental development, diagnoses and management of mental health conditions.

Nutzenadel W. (2011) Failure to thrive in childhood. Deutsches Ärzteblatt International 108:642–649.


Infancy and early childhood are key periods in a person's growth and development. Poor nutrition at this stage can have far-reaching long-term effects. FTT is associated with poor health, poor growth and learning and cognitive difficulties later in life.

That said, a short period of FTT that is treated effectively should have little to no effect on future development.


Relating to cognition, which are the mental processes and abilities associated with acts of judgement, reasoning and understanding.

Nutzenadel W. (2011) Failure to thrive in childhood. Deutsches Ärzteblatt International 108:642–649.


The best way to prevent FTT is to be aware of the child's nutritional status and to ask for help if you are not confident in your knowledge of caring for your child. Nutrition is a complicated subject and parenting is a difficult skill. Parents can often benefit from assistance and guidance.

Nutzenadel W. (2011) Failure to thrive in childhood. Deutsches Ärzteblatt International 108:642–649.

FAQ Frequently asked questions