Vitiligo on hands and feet

Last Updated on 20th February 2024 by Caroline Haye

Why are extremities so prone to depigmentation and so hard to repigment?

Vitiligo can occur absolutely anywhere on the body. (Even on the inside.) No area of skin is off limits as far as this pigmentary disorder is concerned, two of the most common sites being the face and the extremities. (Well, that makes three sites really, since extremities comprise both hands and feet.) But, whereas facial vitiligo responds relatively well to currently available therapies, hands and feet are notoriously resistant. Meaning that these are often among the last areas to improve. And sometimes they never improve at all.

Knowing this, I have sometimes wondered why is vitiligo on hands and feet so common? And also why is it so hard to repigment? Surely there must be a reason. But, strange to say, I have hardly ever seen or heard this question discussed. And I have never come across a definite answer, which is why I decided to look at the subject more closely to see what I could find out.

Six theories

Whilst I’m not aware of any conclusive explanation for this phenomenon, I have read some plausible propositions and can think of one or two more myself. Maybe the answer lies in one of the following six theories, or possibly in a combination of several. Or maybe there is an altogether different explanation. (If you have any additional suggestions, please let me know in the comments below.)

1. Lack of hair follicles

Hair follicles play an important role in the production of skin pigment. And, since we typically have fewer hair follicles on our hands and feet than other areas of our body (at least, compared to arms and legs, for example), it may also follow that we have a lower concentration of melanocytes in these areas. This is certainly true when it comes to our soles and palms, which accounts for the lighter colour of skin in these areas, regardless of whether we have vitiligo or not. It might also explain why our fingers and the underside of our wrists are even more prone to depigmentation and more resistant to treatment than the backs of our hands, where there are significantly more follicles. (And, similarly, the hairless areas of our feet tend to fare worse than the portions that contain more follicles.)

In any case, a relative lack of follicles might help explain why extremities are harder to repigment in cases of vitiligo than arms and legs. But I doubt that is the whole story because other relatively hairless parts of the body (like much of our facial skin, neck and torso) generally respond better to vitiligo treatments. So what other factors might be at play?

2. Excessive sun exposure

Unless we are in the habit of wearing gloves all year round, our hands are exposed to sunlight more than any other part of our body. And, given that sun damage can trigger pigment loss, this could explain why so many people develop the condition on their hands. (As well as on their face, for the same reason perhaps.) It might also explain why it is so hard to recover that lost pigment. Because hands continue to be exposed to UV on a virtually continuous basis.

But, of course, the same cannot be said for feet, which for most of the time are protected from the elements… Having said which, the tops of feet are a common site for sunburn, so that could possibly come into the equation. But it seems to me that the theory that sun exposure alone could account for hands and feet being so prone to pigment loss and resistant to repigmentation does not really stand up to scrutiny. Especially when you consider the apparently contradictory fact that UV light is actually instrumental in producing new pigment. So there must be more going on behind the scenes…

3. Other external triggers

External triggers, such as contact with certain everyday substances and commonly used chemicals, can start the vitiligo process or cause it to spread. This being the case, it seems reasonable to ask the question are our hands and feet at greater risk from these triggers than other parts of our body? And, if so, could that provide an answer to the puzzle? Well, there’s no doubt that our hands come into contact to a greater degree and more frequently with more substances than the rest of our body. We handle all kinds of products, objects and materials every day. We rarely protect our hands by wearing gloves. And, even when we do, those gloves may themselves contain irritants or depigmenting agents (like rubber, for example).

But does this theory hold true when it comes to feet? Not really. At least, not to the same extent. However, many of the dyes and synthetic materials widely used in modern footwear most definitely fall into the category of potential vitiligo trigger. And the sites and patterns of vitiligo which typically develop on feet tend to match the exact position and shape of our shoes. So, might this theory be more plausible than the previous two? Maybe. Especially if you look at it in combination with another known trigger…

4. Koebner effect

The Koebner effect (or Koebnerisation) refers to the development of new skin lesions at the exact site of injury or other skin trauma. It applies to vitiligo and psoriasis, among other dermatological conditions. And it can occur as a result of repeated rubbing or friction, such as when shoes are either too tight or so loose that they rub back and forth as you walk. Tightly fitting socks or boots can also have this effect. Similarly, the phenomenon can affect our hands if we injure them in the course of everyday activities, or even if we rub them dry too roughly or too frequently. (You can read more about this in Why Do Skin Injuries Cause Vitiligo?)

5. Reduced circulation

I remember reading something a long while ago about poor circulation as a possible reason for the difficulty in repigmenting extremities. (Unfortunately, I haven’t been able to find much on it since, so the theory may have fallen out of fashion.) It was based on the fact that, since our hands and feet are at the furthest point from our heart, the blood supply to these areas is poorer, making these areas more prone to injury and infection. Of course, there is no suggestion that vitiligo is linked to infection. But oxidative stress is certainly a part of the vitiligo process. And this would presumably be worse in areas that have poorer blood supply, as this research suggests.

6. Changes to the skin microbiome

Research has identified an imbalance of microorganisms in the skin (and gut) of patients with various chronic skin conditions, including vitiligo. So I suppose it’s possible that this imbalance may, for some reason, be more severe in the skin on our hands and feet than elsewhere on our body, making the spread more likely in these areas and recovery more difficult. One reason for this could be that more frequent washing and / or a higher rate of perspiration on hands / feet disturbs the skin microbiome or increases free radical damage in those areas. As theories go, this may not be a front-runner. But that doesn’t mean it might not be a contributing factor.

My own experience of vitiligo on hands and feet

My own experience may or may not be typical. But I do think it conforms to the notion that vitiligo on hands and feet tends to behave differently from vitiligo elsewhere. My hands were one of the first parts of my body to develop white patches. And they proved to be the most unpredictable during my repigmentation.

Whereas my face and most of my body regained pigment quite steadily over a period of time, the pigment on my hands kept altering as if a limited amount of melanin couldn’t quite make up its mind how to distribute itself. So it kept shifting about from week to week or from month to month. Sometimes (mainly when exposed to sunlight) it formed very dark freckles. At other times the freckles joined into clusters. And finally these islands of pigment lightened and dispersed evenly to leave a uniform colour that was just slightly paler than my normal skin colour with just the occasional light freckle remaining.

So, are we any closer to an answer?

Do any of these six theories really explain why hands and feet are more susceptible to vitiligo and more resistant to repigmentation than the rest of the body? I just don’t know. And I’m not sure anyone would claim certain knowledge about this one way or the other. It’s possible that there is a completely different mechanism at play. Or the truth might be a combination of several factors. And these factors might also vary from one individual to another.

So we may not be much closer to a conclusion than we were at the top of this page. But it’s an intriguing question. And I have found that just searching for possible theories has been an education in itself. As ever, vitiligo continues to fascinate and surprise me, just as it continues to provide researchers with more mysteries to unravel and challenges to overcome. For every answer, it seems there is always be another question. And for every solution, another riddle.

If you are equally fascinated by the complexities of vitiligo you might enjoy reading Why Is Vitiligo So Confusing?

And for more information on the different characteristics and distribution of vitiligo on the body, see Dr John Harris’s blog post entitled Patterns of Vitiligo