Children grow fast however every child may have a different growth rate. The recommended height for an 8 year old boy isn’t as clear-cut as the recommended inches from a specific chart. While there may be an average height for a child of any age, however the average height isn’t the indicator of good heath and growth.
Children of a given age fall within a height range, so the recommended height of an 8-year-old is typically based on percentiles. The 50th percentile is the median height for children, meaning that about 50 percent of children of the same age and gender will be above this height and the other 50 percent will be below this height.
Percentiles
A body mass index that places an 8-year-old above the 4th percentile, yet below the 85th percentile generally means that the child is healthy. BMIs below the 5th percentile indicate underweight, while above the 84th means overweight and above the 95th means obese.
Therefore based on percentiles, the average height of an 8 year old boy with a healthy weight and recommended BMI may be about 4 feet 1 inch tall. This places an 8 year old at the 20th percentile. The average height of an 8 year old boy or even a girl is about 50 inches.
The weight of the child also plays a significant role in the recommended average height.
Once should calculate the body mass index to clarify if the child is of healthy height and healthy weight. To arrive at this number, divide weight in pounds by height in inches and then divide this number by height in inches again. From there, multiply this number by 703 to arrive at your child’s BMI. An 8-year-old boy weighing 50 lbs. at a height of 4 feet 1 inch tall has a BMI of 14.6. This number is then placed on a growth chart to arrive at a percentile. It’s this percentile that indicates if your child is at a healthy weight.
Screening
Even when an 8 year old falls within a certain percentile it doesn’t necessarily mean he’s underweight, overweight or obese for his age and height. BMI is only used as a screening tool for potential weight problems in children. Your pediatrician will likely test skin fold thickness and assess diet and level of physical activity to determine if excess fat is an issue.
