The question
I'm 34 and have pretty great skin. But I've noticed a few sun spots on my hands over the past few months. What are they, and should I be concerned?
The answer
Sun spots are also known as age spots or liver spots, and in medical terms we call them solar lentigos.
They are caused by exposure to natural and artificial (for example, tanning booths) ultraviolet light. In response to UV light, cells in the skin called melanocytes produce increased amounts of pigment known as melanin.
While this increase in pigmentation is meant to protect your skin from the sun, the accumulation of melanin due to chronic sun exposure can lead to the development of these dark spots over time.
They are similar to freckles, but sun spots aren't likely fade in the winter. They are also formed after years of exposure to sun, while freckles can be present at birth or in early life and aren't necessarily related to sun exposure.
Most often, a sun spot will be flat with smooth borders and evenly coloured. They are most commonly found in areas that receive the most sun: your face, neck, hands, arms and shoulders. Because they are due to chronic sun exposure, they are more commonly found in adults over 40 - but it is possible to see them in younger individuals as well. They are more common in those with fair complexions.
On their own, sun spots are not a reason for concern - they are benign. But they do indicate sun damage to your skin, which is a known risk factor for the development of skin cancer.
Sunscreen and sun protection can prevent the development of solar lentigo but will not cure those already in place.
Remember, not all skin changes will be benign. If your spots are changing in colour, shape or size, seek advice from your doctor to ensure that it's not something more serious.
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