There is this myth that a sleeping position can actually result in hair loss. Waking up to find numerous hair strands on the pillow might be a cause of this theory. Seeing some perceived bald patches in the bathroom mirror can also add fuel to this belief. This does not mean however that a sleeping position could instantaneously result in hair loss overnight.
The closest balding condition that could be related to this is traction alopecia. Hair loss results from an abnormal tugging or pulling of hair. Examples of this is styling it in cornrows or keeping it in a ponytail for extended periods of time. Hair is shed in clumps in areas where it has been pulled at the roots. This requires a continued application of force to result in balding. It can cause either temporary or permanent hair loss. Sleeping in one position however does not generate enough resistance to cause the same results as in traction alopecia. It needs also needs to be in a certain state for a longer period of time.
Balding caused by a sleeping position bases its hypothesis on the lack of blood flow reaching the hair follicles. It is true that hair loss will result if this does occur because the bloodstream carries with it essential vitamins and minerals necessary for its development. This is what causes androgenic alopecia, the lack of nutrition reaching the hair follicles. Hormones such as dihydrotestosterone (DHT) bind with the androgen receptors of the hair follicles effectively blocking it off from the circulatory system. This causes the hair follicles to shrink, resulting in hair loss because it cannot receive the nutrition it requires to maintain itself. This has scientific basis and is indisputable.
Shedding of hair due to a sleeping position however, merely relies upon the pressure generated to effectively cut blood flow by lying on a certain spot for an extended period of time. This would not make sense because it would probably require more than a normal sleep cycle before the hair follicle gets malnourished. Male pattern baldness in itself is a gradual condition that takes years before a significant amount of a person’s hairline is observed to have noticeably receded. It would take quite an extended period of time lying down in one position before hair loss can result. This simply cannot be achieved overnight. More importantly, hair follicles shrink when it is cut off by DHT from the blood supply. The hair strands are not shed but gradually reduce in length and circumference with each hair growth cycle until it becomes wispy. Eventually, the hair follicles fail to produce anything altogether.
Finding numerous hair strands on a pillow may be cause for concern because hair is not shed that quickly without a reason. It might be the result of nutritional deficiencies due to a poor diet or an unhealthy lifestyle. Illness, medication and stress are also other reasons that can be attributed to this symptom. It could also be the result of telogen effluvium, a hair loss condition brought about by the sudden shift between the hair growth cycles. This is triggered by stressful events such as major surgery, divorce, loss of a loved one, accident or even childbirth.
In any case, balding is not caused by a sleeping position. Noticing bald areas in the morning might just be hair spread out in a certain way due to the pressure exhibited on it while lying down. Consultation with a qualified physician however should be done immediately if hair is in fact being shed in clumps. Proper diagnosis of a hair loss condition is a prerequisite to finding an appropriate remedy.