An estimated 80% of women wear the wrong bra size, often one that is too small, leading to a range of health concerns beyond mere discomfort, according to Tara Vooght, a research associate in breast biomechanics at the University of Portsmouth.
Physical Ailments
Ill-fitting bras can contribute to significant neck and back pain, which may in turn affect posture and even a person's walking style. The underband of a bra is designed to provide the majority of its support. When it is too loose, the shoulder straps can bear excessive pressure, exacerbating neck and back discomfort. If the shoulder straps are too tight, they can create permanent deep furrows in the skin. Vooght has observed permanent indentations in women who have worn bras that are too tight for years.
Additionally, underwires that are too small can dig into breast tissue, potentially deforming surrounding structures, including lymph glands. It is crucial that the underwire does not press into any breast tissue.
Breast Health and Activity
For some women, particularly those with larger breasts, discomfort from wearing the wrong bra size can be so severe that they seek breast reduction surgery. Some women also refrain from physical activity due to a lack of confidence in the support provided by their sports bras.
Finding the Right Fit
Vooght offers a five-step guide to help individuals find a bra that fits properly:
- Underband: The underband should sit level around the body. If it rises at the back, it is likely too tight. It should be snug, allowing only about a five-centimeter gap when pulled away from the body. It is recommended to buy a bra on its loosest setting so it can be adjusted as it loosens over time.
- Cups: Breasts should be fully enclosed in the cups without bulging or gaping at the top or sides. Most breast tissue extends to the armpit, so it's important to ensure the bra accommodates this. A gap between the breast and the underwire may indicate a cup size that is too large.
- Underwire: The underwire should align with the natural crease of the breast and not dig into any breast tissue.
- Centre Front: The part of the bra between the cups should lie flat against the body. If it lifts away from the chest, a larger cup size may be needed.
- Shoulder Straps: While straps help keep the bra in place, they should not be the primary source of support. Straps should allow for two fingers to fit underneath without digging in or being so loose they slip. It is also common for women to have one breast larger than the other, requiring straps of different lengths. Straps are typically the most adjustable part of a bra and can be adjusted last.
Sports Bras
Finding the correct size for sports bras is equally important, as they often come in generic Small, Medium, and Large sizes that do not account for specific band and cup measurements. A sports bra should offer a snug fit without digging into the shoulders, which can cause chafing and strain. Too large a size will result in a lack of support. The bra should remain in place during movement. Vooght suggests performing star jumps in a changing room to test how a sports bra moves with the body.
Sister sizing, a method where band and cup sizes are adjusted proportionally (e.g., a 34C can be a 32D or 36B), can be a useful solution if the underband fits but the cups are too large or small.