Health care teams and caregivers often turn to us, Dietitians, when a child’s growth is faltering.

As poor weight gain is often the first indication of failure to thrive, the new terminology recommended by AAP is weight faltering.

Chronic struggles with weight often lead to poor gains in length and head circumference and can start to negatively impact development. Early management is key to preventing long term consequences, some of which include poor cognitive development and a weakened immune system.

First Steps:

✔️ Ensure the measurements are accurate and that outliers are re-measured using standardized techniques by trained individuals

✔️ Serial measurements over time, rather than a single point, are required to evaluate weight faltering

✔️ Record and plot on World Health Organization (WHO) growth charts for children up to two years of age

✔️ Use specialty growth charts (e.g. in children born prematurely or with specific diagnoses, such as Turner syndrome or Trisomy 21) in conjunction with WHO growth charts

✔️ Correct for gestational age in premature infant

How to Interpret the Results?

Use the right terminology based on the WHO cut-off criteria to describe growth concerns:

Growth Indicator for 0-2 years

%ile on WHO curve

Growth Concerns


<3rd %ile



<3rd %ile



<3rd %ile


“Cut-off points are intended to provide guidance for further assessment, referral or intervention. They should NOT be used as diagnostic criteria.” (WHO)

Estimate the Ideal Body Weight:

For the patient who is underweight and/or wasted, estimating the ideal body weight (IBW) will help you determine their catch up requirements.

Using the 50th %ile weight-for-length to estimate the ideal body weight

How to Estimate Catch Up Growth Requirements:

Calculation for Catch-Up Energy Requirements

Kcal/kg/day = Ideal Body Weight (IBW) x kcal/kg/day (DRI for age)

Actual weight (kg)

Determine the Etiology:

Where there is weight faltering, it is the Dietitian’s role to understand the mechanism of undernutrition. This is essential to establish the best nutrition care plan as your strategies will need to address the etiology at play.

The primary categories are:

-Inadequate nutrient intake

-Increased energy requirements

-Poor nutrient absorption/utilization

Keep in Mind:

📑 All predictive equations are estimates

📑 Most predictive energy equations were derived from healthy children rather than the hospitalized child who typically has variable energy needs

📑 Determining ongoing or subsequent energy needs should be assessed by using serial weight changes while considering the patient’s medical condition

Important Considerations:

Protein requirements are based on age, need for catch up growth or repletion, and specific disease states. Excess protein delivery > 4 g/kg/day often results in high urea level (buildup of nitrogenous waste). It's important to calculate protein delivery when providing catch up nutrition.

In complex medical conditions, despite adequate macro and micronutrients, length and head circumference may not improve, resulting in disproportionate weight-for-length and increasing the risk of overweight/obesity. Close monitoring and frequent re-evaluation is required.

Bottom line:

You can expect catch-up growth at 2-3 times the average rate of weight gain for corrected age, but we wouldn’t aim for more than that.

Here’s a great go-to resource:

Homan, Gretchen J. Failure to Thrive: A Practical Guide. Am Fam Physician. 2016: 15;94(4): 295-299.

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Wishing you happy holidays,

Charlene and Julie

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