When you try on a new pair of shoes, you may discover that one foot feels tighter while the other feels looser, indicating that your feet are not the same size. Why does this happen, and which foot is typically larger?
According to Corrine Renne, a podiatrist practicing in New York, reported by LiveScience, no one’s two feet are exactly the same. The human body is somewhat symmetrical but not always perfectly so.
A study published in 1983, involving 4,000 women and 2,800 men across the United States, revealed that the sizes or shapes of their two feet were different.
Another study published in 2018, analyzing the feet of 2,890 British individuals, found that the length difference between their two feet exceeded approximately 4 millimeters.
This research indicates a similar trend in the United States, while in China, over 24% of people have a difference of more than 4 millimeters between their two feet.
As to whether the left or right foot tends to be larger, studies do not reach a consensus. While a 1983 study suggested that people generally believe the left foot is usually larger, researchers found that the likelihood of one foot being larger than the other is actually equal.
In contrast, a study published in 2018 found that the right foot is typically longer, with 50.7% of British women and 54.8% of British men having a longer right foot.
Renne stated that a certain degree of asymmetry in the human body is caused by normal variations. “Our hands are not perfectly symmetrical, and neither are our eyes.”
Renne added that other factors could also contribute to the difference in foot sizes. For example, women may experience some discrepancies in foot size during or after pregnancy due to ligamentous laxity. In such cases, their joint range of motion may increase, leading to differences in foot size if they naturally favor using one side of the body.
Various birth conditions can also result in significantly different foot sizes. Jacob Wynes, Associate Professor at the University of Maryland School of Medicine and Director of Foot Services, gave an example of individuals born with clubfoot, where one whole foot may be smaller than the other.
He further explained that brachymetatarsia, a condition where one or more toes are shorter on the foot, can also lead to differences in foot size.
The Center for Foot Care in Ohio noted that injuries can alter foot size, especially during childhood when the bones are still developing. City Chiropody and Podiatry in the UK added that prolonged use of a cast can weaken and atrophy foot muscles, leading to differences in foot size.
Renne supplemented that using one foot more frequently than the other can also result in differences in foot size. For example, ballet dancers may experience this, which could increase muscle mass and thicken the foot structure.
Wynes mentioned that if the difference in foot size is severe enough to affect daily life or cause unbearable pain, surgery may be necessary to correct it. This condition may be the result of foot injuries.
He explained that surgeries like bone transplants or cuts can manually lengthen or shorten bones, with people generally tolerating changes of about 2 centimeters (0.8 inches) resulting from surgery.
In most cases, differences in foot sizes only pose inconvenience and do not require surgery. If you have different foot sizes but want to find suitable shoes, there are ways to address this.
Renne suggested one method of purchasing a pair of shoes that fit the larger foot and using custom devices provided by podiatrists or orthotists, such as padding for toes or heels, to make the shoe more comfortable and symmetrical.
Another method, as Wynes mentioned, is buying two different-sized shoes. Renne added that some specialty shoe stores sell individual shoes for each size.