Causes of Hair Loss

A study published in the Journal of Dermatology and Therpay (2017) revealed that hair shedding is a common consequence of the normal hair growth cycle. This means that it is normal to shed a certain amount of hair at least every day.

However, losing significant amounts of hair is unusual and will cause distress and worry, prompting you to seek the opinion of an expert. There are several causes of hair loss. Your doctor will explore all these causes before settling on diagnosis and recommending treatment.

Heredity (Family History)

Hereditary baldness is by far the most frequent condition of hair loss. It is not a disease per se, but a natural presentation contributed to by a combination of hormonal factors, genetic predisposition, and aging.
According to studies, individuals susceptible to this type of hair loss have follicles that have been genetically pre-programmed to transform from long growth phase and short rest phase to long rest phase and short growth phase.

Many genes have been implicated in causing hereditary baldness. However, studies have only identified the gene which encodes the Androgenic Receptor.

Hormonal Changes

Hormones are at the forefront among the causes of hair loss. Here are the hormones associated with hair loss.


As early as the 1940s, scientists were able to tell that male hormones (chiefly testosterone), were closely linked to hair loss (Hamilton et al., 1942). It had been observed that men who were castrated before puberty never developed baldness even though they were genetically predisposed.

Moreover, men who were castrated after developing hair loss saw a stop in the progression of hair loss. And those who were castrated but were injected with testosterone experienced hair loss. These findings linked high testosterone levels to hair loss.

Dihydrotestosterone (DHT)

About 30 years after studies were first done on testosterone, scientists realized that it is the male hormone dihydrotestosterone (DHT) that is involved in hair loss. Studies have found out that:

  • Men who are unable to produce DHT in their scalp do not experience hair loss.
  • Scalp regions that bald have more DHT than non-balding parts.
  • Medications that target the reduction in scalp DHT improve the outcomes of hair loss by up to 90%.


Most people with prolonged stressful states tend to suffer from hair loss. Stress pushes your hair follicles prematurely into the resting phase. As a result, you don’t produce new hair strands, yet your hair continues to shed. Over time, continuous combing, washing, and touching your hair potentiates your hair loss.


Of all the nutrients in your diet, proteins are among the most important for your hair growth. They are useful in structuring your hair follicles. It is not uncommon to see hair loss in people who eat “crash” or “fad”, sometimes even keto diets. Online reviews by doctors suggest that a high protein diet, enriched with iron, biotin, and other dietary supplements can help prevent hair loss.

Vitamin Deficiency

When you go to the hospital to see your doctor, the doctor will probably tell you that hair loss is one of the possible symptoms of Vitamin B 3 (Niacin) deficiency. Niacin deficiency makes your hair to fall out in patches. Another vitamin that is linked to hair loss is vitamin B7 (biotin). Biotin is an essential component of proteins useful in the hair growth cycle.


Hair loss can sometimes occur as a side effect for certain medications. Cholesterol-lowering medications such as atorvastatin, anticoagulants such as warfarin, medications for blood pressure such as captopril, and medications for psoriasis such as acitretin are among the commonest cause of hair loss. The effect of anticancer drugs on hair loss (chemotherapy-induced alopecia) has also been widely documented.

Postpartum Hair Loss

Hair loss after delivery is a common complaint among women. It is prevalent about three months after delivery. During pregnancy, the hormonal levels increase hair growth, hence the reason why pregnant women seem to have thicker and fuller hair. But by three months after delivery, the levels of these hormones start declining, and hair loss may occur as the body tries to adjust to the change.


There are several causes of hair loss. The ones mentioned above are, by far, the most common. It is essential to know the exact cause of your hair loss to help you decide on the most appropriate treatment option.

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