The Anatomy of Adult Foot Size Change
While most of the body's bones stop growing by the early twenties, the foot's structure is not static. The change in foot size in adulthood is less about bone growth and more about the wear and tear on the ligaments, tendons, and other soft tissues that provide support. Each foot is a complex structure of 26 bones held together by numerous connective tissues. Over a lifetime, these tissues undergo significant stress from carrying body weight and absorbing impact from walking and standing. As the elasticity of ligaments and tendons diminishes with age, the arch of the foot can flatten and lengthen. This flattening can cause the foot to splay out, increasing both its width and length. Furthermore, the protective fat pads on the soles of the feet naturally thin out over time, reducing the cushioning between the bones and the ground and affecting the overall shape.
Why Adult Feet Get Bigger
Several key factors contribute to these structural changes. One primary driver is the natural aging process itself. Years of consistent use cause the supportive ligaments and tendons to stretch and loosen, a process known as ligament laxity. This relaxation of tissues allows the foot's arch to gradually collapse, leading to a wider and longer foot print. It's not uncommon for people to notice their shoes from their 20s no longer fit comfortably decades later.
Another significant contributor is weight gain. When carrying extra weight, the additional pressure on the feet can further stress and stretch the ligaments and tendons. This can lead to a more pronounced flattening of the arch and spreading of the foot. In some cases, significant weight loss can cause a slight reduction in foot size, although the changes caused by ligaments stretching may be permanent.
Pregnancy is a major cause of temporary and sometimes permanent increases in foot size for women. During pregnancy, the body produces the hormone relaxin to soften ligaments and joints in preparation for childbirth. This hormone also affects the ligaments in the feet, which, when combined with increased body weight and fluid retention, can cause the arches to fall and the feet to widen. For many women, this change is permanent, necessitating a larger shoe size.
Medical Conditions Affecting Foot Size
Beyond natural aging and weight fluctuations, certain medical conditions can also cause feet to increase in size or change shape. Conditions like arthritis can affect the joints in the feet, leading to inflammation and swelling. Diabetes can cause poor circulation and nerve damage (diabetic neuropathy), which can result in swelling (edema) in the extremities. Over time, these issues can permanently alter the foot's structure. Foot deformities like bunions—a bony bump on the joint at the base of the big toe—can also cause the foot to widen and require a bigger shoe size to avoid pain and further problems.
Managing Foot Size Changes
Recognizing that your foot size can change is the first step toward maintaining proper foot health. Continuing to wear shoes that are too small or tight can lead to a host of problems, including painful bunions, hammertoes, and other deformities. Regular foot measurements are crucial, especially when buying new footwear. You might find that your shoe size and width have changed over the years.
Tips for accommodating your changing feet:
- Get Measured Regularly: Always have both feet professionally measured, especially in the late afternoon when they are at their largest due to natural swelling.
- Prioritize Fit Over Number: Pay attention to how a shoe feels, not just the size printed on the box. Shoe sizing can vary significantly between different brands and styles.
- Choose Supportive Footwear: Opt for shoes with proper arch support, cushioning, and a wide toe box. This supports the foot's structure and helps prevent flattening and other issues.
- Consider Orthotics: If you have fallen arches or chronic foot pain, orthotics can provide additional support and correct biomechanical issues.
- Strengthen Your Feet: Simple foot exercises can help strengthen the muscles that support your feet and improve overall stability.
Foot Size Change Causes: A Comparison
| Cause | Mechanism of Change | Potential Outcome | Permanence | Recommended Action |
|---|---|---|---|---|
| Aging | Ligaments and tendons lose elasticity, causing arches to flatten and feet to spread. | Feet become wider and longer; shoe size increases. | Mostly permanent, as tissues have stretched. | Regular measurements, supportive footwear, foot exercises. |
| Weight Gain | Added pressure on feet causes ligaments to stretch and arches to flatten. | Feet become wider and flatten; shoe size increases. | Can sometimes be partially reversible with weight loss. | Maintain a healthy weight, wear supportive shoes. |
| Pregnancy | Hormones (relaxin) loosen ligaments; increased weight and fluid retention cause swelling. | Feet lengthen and widen; shoe size may increase. | Can be permanent for some, temporary for others. | Wear comfortable, supportive shoes; consider compression socks. |
| Medical Conditions | Inflammation (arthritis), swelling (edema from diabetes, heart issues), deformities (bunions). | Foot shape and size are altered; shoes no longer fit. | Dependent on the underlying condition and treatment. | Consult a healthcare professional (podiatrist); wear prescribed orthotics if needed. |
Conclusion
So, can your shoe size increase as an adult? The answer is a clear yes. While it's not the result of ongoing bone growth, the dynamic nature of your foot's anatomy means changes are to be expected. Factors ranging from aging and weight gain to pregnancy and certain medical conditions can alter the size and shape of your feet over time. By staying proactive and wearing properly fitting, supportive footwear, you can ensure your feet remain healthy and comfortable throughout your life.
Visit the Foot & Ankle Center of Washington for more information on feet getting bigger.
