There are many causes of hair loss, ranging from genetic disposition to side effects of drugs, illnesses or imbalance in the body. Determining the cause of hair loss can come down to a blood test. While a blood test will not show a positive or negative for a hair loss gene, it may reveal another cause behind the loss.
Hormonal disorders, like hypothyroidism, can cause hair loss and may be detected by a blood test known as the thyroid stimulating hormone test, or TSH. Another hormonal imbalance that causes hair loss, menopause, can be detected by a blood test called a follicle stimulating hormone test, or FSH. Both the TSH and FSH are able to indicate these and other hormonal conditions that cause hair loss. They work by giving a measure of the amount of hormone present in the bloodstream.
One of the most commonly known illnesses that causes hair loss is alopecia. Although there are different types of the illness, it is generally caused by the body building an immunity to the patient’s own hair. The blood test for alopecia is a fluorescent antinuclear antibody test, or FNA. The presence of antibodies in the bloodstream can mean the body has built this defense against its own hair.
Iron-deficiency anemia, which occurs when there is too little of the mineral iron on the blood, can be detected with a blood test called a ferritin level test. A low ferritin level can signify an iron deficiency. A complete blood count, or CBC, is like a snapshot of the blood, giving a count of the red and white blood cells and platelets. The result of that count can reveal infections, cancers, and deficiencies in minerals like folic acid and vitamin B12. The results can also uncover dehydration.
Undetected by Bloodwork
Sometimes causes of hair loss are not determined by blood tests. These include depression; telogen effluvium, which is often seen in people who are grieving the sudden loss of a loved one or who are victims of other traumatic experiences; and traction alopecia, which is hair loss due to aggressive hair styling. These kinds of hair loss can be temporary.
What to Expect
If you are experiencing hair loss, do not hesitate to see your doctor. If it is a first visit, expect the doctor to take a patient history before ordering blood tests. He will ask about your history of health problems and those of your family, because some hair loss causes, like alopecia, are genetic. Be honest with your doctor. There are other causes not listed here that require a complete patient history to detect. For example, sexually transmitted diseases, like syphilis, can cause hair loss, as can certain drugs, whether prescribed or illegal.