Last reviewed: September 29, 2026

No more than about 15% of your child’s body weight. A heavy backpack can hurt while it is being carried, but good studies have not shown that it leads to back pain later on or causes scoliosis.

The American Academy of Pediatrics advises that a full backpack weigh no more than 15% of a child’s body weight. For a child who weighs 100 pounds, that is 15 pounds. Lunches, water bottles and laptops all add to the weight.

Studies that followed children over time found that children who carried heavier bags were not more likely to develop back pain later. Children with a school locker reported less back pain.

How the bag is carried may matter. Studies that followed children for several years linked carrying a bag on one shoulder to later back pain, although not all studies agree. Pediatric and orthopedic groups advise wearing a backpack on both shoulders, with the straps tightened so the bag sits close to the back.

A rolling bag is another choice for heavy loads, if the school allows it. In a study of schoolchildren, pulling a rolling bag changed walking and posture less than carrying the same weight in a backpack. No study has measured back pain in children who use rolling bags.

According to the American Academy of Orthopaedic Surgeons, heavy backpacks do not cause scoliosis. Scoliosis specialists say a heavy backpack will not make an existing curve worse. Children who already have scoliosis balance less well under heavy or one-sided loads. For them, one review advises using both straps and keeping the bag under 10% of body weight.

Slouching has not been shown to cause back pain. Lessons on posture improve posture and habits, but they have not been shown to prevent back pain.

In general:

  • Weigh the full backpack from time to time, with the lunch, water bottle and laptop inside.
  • Use both straps, tighten them, and pack heavy items low and close to the back.
  • Carry only what is needed that day, and use a locker if one is available.
  • See your child’s doctor for back pain that does not get better, or that happens when the child is not carrying the bag.

Drafted with AI assistance from published sources, reviewed and edited by Babak Sheikh, MD.

Sources:

This is general information about what published research shows. It is not medical advice and it is not about your situation. Reading it does not create a doctor-patient relationship with me. I am a retired orthopedic surgeon and I do not see patients. Talk with your own doctor before changing anything about your care. If something feels suddenly or seriously wrong, get medical care promptly rather than waiting.

This page is provided as is. I make no guarantee that it is accurate, complete or current, and medical evidence changes. Use of it is at your own risk.

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