If you feel like every time you turn around your child is growing, you may not be imagining it. Peak height velocity—your child’s biggest, fastest spurt—typically lasts 24 to 36 months. During this time, females grow an average of 9 cm per year and males an average of 10.3 cm per year, according to the University of Southern California.
But, how growth happens involves a complex system of plates and hormones that make it unlike anything else. “In contrast to trees, which grow from the ends, a child’s bones cannot just add more tissue to their ends,” explains Francisco Rosales, MD, ScD, medical director of scientific and medical affairs at Abbott.
Instead, our bones grow from the inside out. Each bone is equipped with growth plates, specialized growth centers. The plates’ cells, called chondrocytes, produce and distribute cartilage along the length of the bone. That cartilage is then calcified and transformed into hard bone. This process extends through the length of the plate and makes bones longer.
Why It’s Important to Identify Growth Spurts
Growth spurts are fueled by a delicate interplay of hormones, genetics and, you guessed it, nutrition. While some nutrients such as calcium and phosphorus form the literal “building blocks” of bone and tissues, others such as vitamin D and zinc play regulatory roles, explains Jennifer Williams, MPH, research scientist at Abbott.
During this time, it’s important to make sure that your child’s intake of calories, protein, vitamins, and minerals support healthy growth. Williams recommends using daily nutrition guidelines to incorporate a variety of healthy foods and nutrients into your kid’s diet. “Offering new foods from each of the food groups on a regular basis helps ensure that a child receives the nutrients they need for growth,” she says.
6 Signs Your Kid’s Having a Growth Spurt
1. She Is Always Hungry
With the increasing nutrition needs associated with growth, your child will likely experience a surge of hunger before and during growth spurts, which can last an average 24 to 36 months. Make sure that these additional calories are coming from whole, nutritionally dense foods rather than snacks and sweets.
2. He Recently Started Puberty
Peak height velocity, the period in which a child experiences the fastest growth, largely coincides with puberty, according to a 2015 study published in the Journal of Clinical Research in Pediatric Endocrinology. This study found that 95 and about 70 percent of girls and boys, respectively, achieve peak height velocity during puberty. The average girl reaches peak height velocity at 12.1 years and males at 13.7 years.
3. All of His Pants Are Suddenly Too Short
Children’s legs tend to grow before their torsos do. In fact, leg length and sitting height (aka torso length) can be used to predict the age at which your child will hit peak height velocity, according to the University of Saskatchewan.
4. She Sleeps More Than Usual
A lot of growth happens during sleep because secretions of human growth hormone peak throughout the night. To support healthy growth, the National Sleep Foundation recommends that children ages six through 13 sleep for nine to 11 hours per night. Teens ages 14 through 17 need eight to 10 hours.
5. She Is Suddenly Crashing Into Everything
During growth spurts, rapid changes in height and limb length can cause their center of gravity to shift, according to the American Academy of Pediatrics. You may notice that they’re more clumsy and accident-prone than usual.
6. He Is Gaining Weight
It is normal for your child’s weight to peak during their growth spurt. Pay attention to weight concerns arising during this time, and be sure to provide constant support. This jump in weight can sometimes contribute to future body image issues, according to a 2015 review in Adolescent Health, Medicine and Therapeutics.