Failure to Thrive: My child is underweight, what should I do?

As a parent, it’s hard to hear that your child has been diagnosed with Failure to Thrive, often written as “FTT.” I often talk to parents who are confused by the diagnosis and not sure exactly what it means, so I thought I’d take the time today to answer some basic questions.

For those who don’t know, FTT is a medical term and is used to describe poor weight gain over an extended period of time. It is often used when diagnosing infants, children and the elderly.

What’s the background on Failure to Thrive?

FTT has been used for more than a century when diagnosing those who are unable to grow or maintain their weight properly; however, it still lacks concise guidelines because it describes a condition and not a disease.

Most diagnoses of FTT are in infants and children and can be a result of something else that may be going on — such as food allergies. The first few years of life are very important for growth and development; therefore it is important to ensure that your little one is gaining the proper amount of weight and has proper nutrition. Most babies double their birth weight by 4 months and triple it by age 1; however, children with FTT often don’t meet those milestones and are lagging on their growth charts.

What causes Failure to Thrive?

FTT can be the result of a variety of social and medical factors.

Social Factors. With obesity on the rise, many parents fear that they are “over-feeding” their children, so they may restrict calories. You will be happy to learn that children (especially young ones) are excellent self-regulators. They lack the desire to eat simply because food is present or out of boredom, which many of us do not! They eat out of necessity and because their body needs the nutrients the food will provide. With that said if you have a young child, follow their hunger cues. If you feel that they are gaining weight too quickly later in life, you may want to consult your doctor or dietitian.

Medical Factors. Most often FTT is caused by allergies or GI conditions such as:

  • Gastroesophageal Reflux Disease (GERD), which can cause an irritated esophagus which may cause a child to refuse to eat;
  • Chronic Diarrhea which causes the body to rapidly lose important nutrients and calories provided by food;
  • Food Allergies to proteins in things like milk which require a restrictive diet that may lead to the inability to maintain or gain weight; or
  • Illness when the body goes into overdrive trying to fight the infection, using up all of the nutrients it has stored to do so.

How is Failure to Thrive treated in infants and children?

Depending on the cause of FTT, it may be easier than you think to help your little one gain the proper weight he or she needs to get back on the growth charts. If it’s caused by a disease or condition such as GERD, Short Bowel Syndrome or a milk protein allergy, you may want to introduce an elemental formula such as Neocate. This will not only aid in weight gain, but can also help with the condition itself. Another option would be to add a product that contains additional fats and carbohydrates like Duocal. It has no protein added and is virtually tasteless, allowing you to add it to foods or drinks consumed by the most picky and allergy-ridden eaters.

If you have been told that your child has FTT, make sure that you have your doctor note it on any medical necessity letter or documentation. This may provide some leverage when applying for reimbursement for elemental formulas.

Have any of your little ones been diagnosed with FTT? How are you helping them to gain weight?



Published: 02/09/2010
Rob McCandlish
Hi Ann, If your child's healthcare team advises to avoid products with coconut oil and MCTs (often from coconut oil), it's best to ask their advice. They may suggest another source of carbohydrate or fat to add extra calories. Polycal is a product we offer made from only carbohydrates that you could ask the healthcare team about. Best of luck!
What if my child has sensitivity to coconut oil or MCTS oil and all the formula in the world has MCT in it including Doucal ,which I Hoped it will help but didn’t.
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