10 Causes of Hair Loss and Baldness

Hair loss — whether baldness or noticeably thinning hair — can occur for a number of different reasons. Sometimes hair loss is a side effect of a health problem that needs to be addressed and will remedy itself when the health problem is properly treated. When hair loss is due to a condition involving the hair itself, as in the case of alopecia, the hair loss can be permanent.

Either an underactive thyroid, a medical condition called hypothyroidism, or an overactive thyroid, or hyperthyroidism, can result in hair loss because each condition causes a hormonal imbalance. Hormones help to regulate nearly every function in the body, including hair growth. Getting the right treatment to control either of these thyroid conditions will get hormones under control, stop hair loss, and allow your hair to starting grow back.

Other hormonal imbalances can also lead to hair loss, especially the wildly fluctuating hormones that occur following pregnancy and childbirth. It takes time after pregnancy for hormone levels to return to normal, so it's not at all uncommon for post-partum moms to notice thinning hair or even patches of baldness. This often occurs about three months after baby’s arrival. Don't worry — as the rest of your body recovers, so will your hair follicles. The hair loss is only temporary — your hair will grow back.

Hair loss is a side effect of a number of medications taken for common health problems. Blood-thinning medications, oral contraceptives, drugs for depression, NSAIDs, and beta and calcium channel blockers can all lead to thinning hair or baldness. Too much vitamin A and vitamin A-based drugs called retinoids can cause hair loss as well. Some chemotherapy drugs used to treat cancer are known to cause total hair loss as they work to destroy cancer cells. Just as hair usually grows back after chemo, it should also grow back once you stop taking any medication that causes hair loss.

Alopecia is the medical term for hair loss, and there are two main types: alopecia areata and androgenic (androgenetic) alopecia. Alopecia may cause hair loss only on the scalp or all over the body. It may result in thinning hair, patches of hair loss, some balding, or total baldness, and it may be permanent or temporary. There are numerous causes, including genetics. Talk to your doctor about possible treatments.

When your body is under serious physical stress, the natural cycle of hair growth and resting can be disrupted, resulting in hair loss, often in the form of thinning hair — strands may come out in clumps. Any shock to the system, such as being in a severe accident, undergoing surgery, experiencing burns, or becoming very ill, can also shock the hair follicles, resulting in up to 75 percent of your hair falling out, sometimes months after the fact.

When you're dealing with a life-altering event, like a divorce or break-up, bankruptcy or other financial problems, the loss of a home, or the death of a loved one, significant emotional stress can also disrupt the normal cycle of hair growth. Significant emotional stressors can cause temporary hair loss, but once stress is brought under control, normal hair growth is usually restored.

The essential vitamins and nutrients, like protein, that you get from a healthy, varied, and well-balanced diet ensure good health all throughout your body, making sure all your organs and internal systems are working just as they should. Poor nutrition or following a severely restrictive crash or fad diet can lead to all kinds of nutrient deficiencies, which in turn can result in hair loss, from thinning hair to patches of baldness.

In an effort to create a stylish hairdo, you can actually cause significant damage and breakage to strands, which could result in hair loss and thinning hair. Shampooing or blow-drying too frequently, repeatedly using heated styling tools, pulling on hair — whether from blow-drying it or styling it in a too-tight ponytail, for instance — or too vigorously rubbing the scalp can all lead to hair loss.

A number of infections and illnesses can lead to hair loss. An infection that causes a high fever, a fungal skin infection, and bacterial infections like syphilis can all be responsible for balding or thinning hair. Treating the underlying infection can restore hair growth and prevent future hair loss. So your first step is to seek medical attention for the primary health problem.

Alopecia areata is often associated with an autoimmune disease, so it's thought that some forms of hair loss can be caused by one of these medical conditions or is at least somehow related to it. Diabetes and lupus are two autoimmune diseases that can result in hair loss. This type of hair loss may not always be reversible — it may sometimes be permanent. But medications and hair restoration surgeries may help compensate for any hair loss.