Bunions are a foot deformity that occurs when the bones in the front part of the foot move out of place, causing the tip of the big toe to get pulled toward the smaller toes and forcing the joint at the base of the big toe to stick out. The exact cause of bunions is unknown, but there are several factors that can contribute to their development, including:

• Inherited foot type: Certain foot types can make a person more prone to developing bunions.
• Foot stress or injuries: Repetitive micro-trauma, possibly from wearing shoes with a heel lift and narrow toe box, can cause bunions to develop in adulthood.
• Deformities present at birth: Some babies are born with bunions, and tweens and teens between the ages of 10 and 15 may develop bunions.

Wearing tight, narrow shoes with a pointed toe box can also cause bunions or make them worse. However, experts disagree on whether footwear is the primary cause of bunions or whether it simply contributes to their development.

In summary, bunions can be caused by a combination of factors, including inherited foot type, foot stress or injuries, and deformities present at birth. Wearing tight, narrow shoes with a pointed toe box can also contribute to their development.