Most of us do not consider hair loss to be a serious medical condition. In most cases it is not when it comes to hair loss on the scalp. When hair loss occurs elsewhere on the body then it needs to be investigated further in order to identify the possible cause as often it can be a symptom of some underlying disease. With regards to hair loss on the legs, it can occur with a host of different problems including conditions that affect blood circulation in the legs, disturbances in the hormone levels, and certain skin diseases.
Hair Growth on the Legs
Fine hair is present on the legs from the time of birth. This is known as vellus hair. With puberty, the head becomes thicker and longer. This is known as terminal hair. It arises in response to the changing hormone levels that marks puberty, mainly with the increase in the male sex hormones known as androgens. Testosterone is one such male sex hormone and is present in both males and females.
Removal of this hair by traditional methods such as shaving is only a short term solution. The hair will regrow in due course as removal only involves cutting of the shat. Certain new generation hair removal techniques, such as electrolysis, may result in more long-term cessation of hair growth due to destruction of the hair follicles. However, these options which are mainly done for cosmetic purposes are voluntary.
When hair growth ceases on its own accord and, then it has to be investigated further for a possible medical cause. It is important to note that hair growth occurs in different phases. In the anagen phase, hair growth is active and the shaft of the hair increases in length. This is followed by the catagen phase. Here hair growth stops and the follicle shrinks. Next is the telogen phase where the follicles enter a resting stage. No growth occurs at this time.
Causes of Hair Loss on the Legs
There are several possible causes of hair loss on the legs. Most involve either a disruption in the oxygen and nutrient supply, the hormonal stimulus for growth, trauma to the follicle or the health of the skin, or a disruption in the cycle of hair growth. Hair loss on the legs is not a serious condition. It is a sign of some underlying problem and for most people it is nothing more than a cosmetic concern. Unlike with the scalp, hair loss on the legs may not be noticed as falling hair on the linen or in the shower. Most people do not notice it until there is significant hair loss.
Circulation in the legs
In order for hair to grow, it requires a supply of oxygen and nutrients to the hair follicles. Any circulatory condition that leads to insufficient blood reaching the legs may therefore affect hair growth. This is mainly seen peripheral artery disease (PAD). In this condition and the arteries carrying blood to the legs are narrowed, usually due to the presence of atherosclerotic plaques that build up in the artery walls.
As a result, blood flow is restricted. Oxygen and nutrients are not delivered as efficiently for health hair growth. The circulatory disturbance in conditions like peripheral artery disease may not always be obvious at the outset but as the condition progresses, a person may experience pain in the legs when walking, sores on the legs may develop, and the legs may feel cold to touch and appear pale.
Any disruption in the hormone levels, specifically those involving androgens can compromise hair growth anywhere on the body, including the legs. This does not only apply to males, because androgens are known as the male sex hormones. These hormones are also present in females but to a lower level. With hormone disturbances, the hair loss is usually not isolated to the legs alone.
It tends to be systemic meaning that it affects the growth of terminal hair anywhere on the body, including that of the chest, armpits, groin region and the beard. Problems with hair growth may also be seen in other hormonal problems, such as hypothyroidism. In this condition the levels of circulating thyroid hormones arise due to a problem with the thyroid gland. Hair loss or thinning hair on the scalp is a common feature of hypothyroidism, and tends to be more prominent in females.
A host of different skin diseases can result in hair loss on the legs. If the skin is damaged for any reason then the follicles may also be involved and normal hair growth will not be possible. This can be seen in conditions like psoriasis, contact dermatitis, eczema and fungal infections of the skin. In these instances the lack of hair growth is not the only symptom. These are usually other symptoms present and the skin in the area is affected which may be visible as a rash.
Hair follicle damage
If the follicles are damaged in any way, hair growth is not possible. It may either be temporary or it can be permanent. In the event of permanent damage, hair growth can never be restored. Damage to the hair follicles may either be as a result of trauma to the legs, for example in the event of burns. Alternatively it can be a complication of certain procedures, like hot waxing or other cosmetic procedures. It is therefore important that hair removal procedures are only done by skilled professionals.
Hair loss may also seen with poisoning but this is an uncommon cause. It depends on the type of poison in the system and hair loss is a characteristic symptom off thallium poisoning. It may also occur with various other substances and toxins. Another possible cause which is sometimes considered to be poisoning, is a condition known as hemochromatosis. In this condition there is a build up of iron in the body but it is usually not due to an excessive intake of iron. Rather the body has a problem with the processing of iron and this leads to an accumulation within the body tissues.