Noticing “bleach” patches on underwear has puzzled many, but the explanation is quite straightforward and linked to the body’s natural processes.

These discolorations are caused by the acidic nature of the vagina, which has a pH range of 3.8 to 4.5. This acidity is a healthy sign, playing a key role in preventing infections by inhibiting harmful bacterial growth.

Dr. Vanessa MacKay of the Royal College of Obstetricians and Gynecologists clarifies that the vagina’s ability to self-clean through its secretions, which can lead to these light patches on fabric, is a normal function supported by beneficial bacteria. It’s a misconception that these patches are a result of poor hygiene.

In fact, they indicate a well-balanced vaginal environment. Understanding this helps demystify the body’s natural processes and emphasizes the importance of maintaining the natural pH balance for overall vaginal health.