Having a teenager at home means encountering surprises regularly—or at least learning to roll with them. But last week, I was truly shocked when I saw the bare back of my nearly 16-year-old son. His entire lower back was covered in purple stripes, known as growth striae.
Table of Contents
I'm not talking about one stripe, but several purple stripes running horizontally across my teenager's back. My initial joke about rough play earned an eye-roll, but upon closer inspection, even he was curious. Seeing purple growth stripes on the back of a lean, growing adolescent boy wasn't what I expected.
I first thought they looked like striae, typically associated with rapid weight gain, such as from overweight or pregnancy. Though I avoided them during my own pregnancies despite a large belly, I recognize the appearance. I initially assumed it was from exercise and would fade soon—but the growth stripes persisted.
It turns out this happens not just in overweight kids, but from rapid growth alone.
Growth stripes are narrow, horizontal lines on the back, sometimes several millimeters thick. They start purple but fade to lighter or whitish over time, just like familiar striae. They're essentially subcutaneous scars.
These stripes result from your adolescent's rapid growth spurt. My son grew about 20 centimeters in the past year—he's now taller than me and nearly matches his dad. His pants are too short, and T-shirts ride up, exposing his midriff.
The fast growth stretches the subcutaneous connective tissue, leading to these purple stripes.
Growth stripes often begin with itching. We didn't notice much here—my son either ignored it or it wasn't bothersome.
You cannot completely remove growth stripes. On reduction (or stretch marks in general), experts differ. However, keeping skin supple helps. I've used Bio-Oil on my face and my daughter Lotte's facial scar with good results—it maintains suppleness and seems to have minimized her scar. Since growth stripes are scars, it's worth trying.
Bio-Oil is available at drugstores or online at a discount.
While you can't eliminate them entirely, support healthy skin to minimize growth stripes:
My teenager's take? "I'm not smearing it on, Mom—I don't mind." Acceptance is a valid option too!
