Why am I Losing my Hair???
Hair loss is a distressing problem experienced by men and women. Here we discuss how female hormonal changes impact hair growth and loss and when to seek help from your healthcare provider.
Hair loss is a distressing problem for both men and women and becomes more common with age. It can also occur as a result of certain medical conditions, infection, autoimmune disease and certain conditions and stages of life where hormonal changes are occurring. Mid-life women are particularly vulnerable to hair loss due to changing hormones and increasing incidence of other medical conditions, such as thyroid disorders, among others. For this reason, it is important to be knowledgeable about the causes of hair loss and the physical signs that suggest the need to seek medical attention.
Hair grows in three stages: Anagen, also known as the “growth phase” is where hair is actively getting longer. 85-90% of hair is in this stage at any one time. Catagen is a “transitional phase” where hair growth slows and the hair follicle gets smaller. 2% of hair is in this phase. The third stage is Telogen or the “resting phase” where hair stops growing and eventually falls out. 10-15% of hair is in the telogen stage. During normal hair growth cycles, we lose approximately 100 hairs per day.
Hair growth and loss is highly regulated by the endocrine system. Androgen, or “male hormone” effects on hair are complex. Circulating androgen levels in the blood can cause an increase in hair growth on the face and midline of the body (pubic, axillary (arm pit) and chest hair) while it can cause hair thinning and loss on the scalp. Eyelashes are not responsive to androgens at all. These differences in how androgens exert their effects on hair in different locations of the body are due to different enzyme and receptor concentrations in these tissues.
Enzymes are like “referees” that dictate how different types of androgens are converted to more potent androgens in a particular tissue.
Receptors are proteins on the surface of cells that are like “antennae” that receive and regulate the hormonal “messages” directed by the enzyme “referees” to the cells and tissues.
Every tissue has a different set of “referees” and “antennae” that take androgens from the bloodstream and process these signals specific to the target tissue. But hold on, this gets even more complex. Estrogen, Progesterone and the insulin growth factor (IGF-1) pathways regulate the effect of androgens through its own set of “antennae” and “referees”. Thyroid hormone, and cortisol impact the hair follicle outside of the androgen system by affecting the hair shaft and the follicle itself.
This complex interplay between the widespread components of the endocrine system and hair growth is why we see changes in our hair in response to stress, pregnancy, hormonal changes, menopause, medications and chronic disease.
During the menopausal transition, two common scenarios are hair thinning at the scalp and an increase in facial hair. This is due to fluctuating estrogen, progesterone and androgen levels as well as changing ratios of these hormones that impact hair follicles in these areas of the body differently. Also common is a “diffuse” loss of hair where excessive hair may be seen in the hairbrush or the shower drain. These changes along with trialing different hormone therapy preparations can create a situation where a greater percentage of hair follicles exist in the Telogen phase ultimately leading to loss of that hair. This is called “Telogen Effluvium”. So rather than losing 100 hairs per day, one can be losing up to 30-50% of hair at any one time. This situation is typically temporary, as these follicles in the telogen phase will ultimately reset the cycle and enter the growth phase again. Telogen Effluvium is also seen commonly after childbirth and after changing hormonal preparations. Hair loss may not be seen until 2-3 months after the inciting event.
When hair loss is significant or is focal with the emergence of bald spots, it is important to speak to your provider to evaluate for other medical causes such as thyroid disorder, autoimmune conditions, fungal infections, diabetes and adverse reactions to medications.
These conditions are often treatable. Certain vitamin deficiencies such as iron, vitamin D, zinc, biotin and selenium can also cause hair thinning or loss. Dietary modification, appropriate supplementation and consultation with a nutritionist may be helpful.
Awareness of your symptoms and attention to their surrounding circumstances are the first steps in helping you and your providers address your situation safely and effectively.