Most people consider stress to be psychological, but a variety of things can inflict physical stress on our bodies, including a very high fever, significant weight loss from dieting, pregnancy, and surgery. Emotional stress—such as grieving or depression—can also play a role in hair loss. When hair is lost due to stress, it is almost always temporary.
Hair can be damaged by hair weaves and hairstyles that pull on existing hairs. This type of hair loss is so common there’s even a name for it: traction alopecia. It one of the most common causes of hair thinning in African-American women, but traction alopecia can affect women of any ethnicity.
Medication and medical treatments
With chemotherapy being the obvious example, there are numerous medications reported to be associated with hair loss. Some anti-inflammatories, anti-hypertensives, and hormone replacement therapy have also been associated with hair loss. Radiation therapy administered to the head may result in hair loss as well.
When choosing an oral contraceptive or hormone replacement medication, it’s important to discuss your concerns and goals with your physician, as these medications can vary in the levels of different hormones they supply.
Local and systemic diseases
This includes a wide variety of different medical conditions associated with hair loss: anemia (low levels of iron or ferritin), nutritional abnormalities, some autoimmune diseases (such as lupus and rheumatoid arthritis infections), and hypothyroidism, to name the most common.
In many of these cases, the patient has an underlying genetic risk for hair loss, and the active process accelerates it. Attempts to determine the disease are undertaken to slow down or even stop the progression of the hair loss, but usually doesn’t result in any significant degree of hair regrowth.