The short answer to whether a woman’s feet keep growing as she ages is no, not in the biological sense of bone lengthening, but yes, they absolutely change size and shape. The bones in the feet reach their full length during adolescence, but surrounding tissues are subject to decades of mechanical stress and hormonal shifts. This leads to alterations in foot dimensions, often resulting in the need for a larger shoe size later in life. The adult foot undergoes significant structural changes that account for the perceived increase in size.
The Difference Between Growth and Change
The difference between growth and alteration lies in skeletal maturity. True growth, the lengthening of bones, occurs at specialized sites called growth plates. In females, these growth plates typically close and harden into solid bone around the ages of 14 to 15. Once the growth plates have fused, the bones in the feet can no longer increase in length, marking the end of biological growth.
Any subsequent increase in foot size is due to the gradual remodeling of the foot’s structure, not bone lengthening. The foot is supported by a complex network of ligaments, tendons, and 26 bones that form an arch. Over time, the supportive soft tissues stretch, causing the arch to flatten or collapse slightly. This causes the foot to elongate and widen.
This structural change is an adult alteration. The physical change is a response to mechanical forces and tissue elasticity changes, not an active biological lengthening of the skeleton. When a woman needs a larger shoe size in her 40s or 50s, she is accommodating a foot that has flattened and spread.
Key Drivers of Adult Foot Alteration
Changes in foot size are rooted in cumulative mechanical stress and age-related tissue degradation. By age 50, the average person has walked approximately 75,000 miles, placing repetitive pressure on the foot’s architecture. This sustained load causes ligaments and tendons to gradually lose elasticity, contributing to permanent structural change.
Increased body weight is another significant factor because the foot must support the entire body load with every step. Sustained weight gain places greater downward force on the arch, accelerating the flattening process and causing the foot to spread and widen. Even without weight gain, the natural aging process causes ligaments and tendons to loosen over time, leading to arch collapse and foot elongation.
Scientific studies tracking women’s foot dimensions have quantified these changes. Research shows that older women have significantly greater foot-shape measurements. For example, ball widths can increase by 3.1 to 4.0 millimeters per decade, and ball circumferences by 5.6 to 7.4 millimeters per decade. This spreading and widening of the forefoot is a common outcome of decades of mechanical wear.
The Specific Impact of Pregnancy
Pregnancy is a unique and powerful catalyst for foot alteration due to hormonal and mechanical changes. During gestation, the placenta releases a hormone called Relaxin, which is designed to soften and loosen the ligaments in the pelvis to prepare for childbirth. This hormone circulates throughout the body, affecting ligaments everywhere, including those in the feet.
As the ligaments in the feet become more lax, the supportive structure of the arch weakens, leading to arch collapse. The mechanical stress of rapid weight gain during pregnancy further exacerbates this flattening effect. The combination of hormonal laxity and increased load causes the foot to elongate and widen, often resulting in an increase of a half-size or more.
The structural changes caused by Relaxin and arch collapse are frequently permanent. The stretched ligaments do not always fully regain their original tension, meaning the foot’s increased length and width often persist long after delivery. For many women, this permanent alteration necessitates a new, larger shoe size for comfortable wear.