When you’re a president of such big country as the USA be ready that people will discuss everything – from the alleged affairs with porn stars to strange spots on your face that could be a sign of a disease.

Recently, the internet exploded with a new portion of viral photos of Trump’s skin that has scaly spots.

As it has been reported previously, Trump has rosacea, a reddening skin condition and that’s why he takes antibiotics to combat. Makeup artists have also speculated that Trump’s facial coloring suggests he uses self-tanner or a tanning bed.

But according to dermatologist Kathleen Suozzi from the Yale School of Medicine, who spoke with Business Insider, the barnacle-looking patch of skin on Trump’s face is probably not a sun spot, and it likely has nothing to do with his rosacea or tanning regimen, either – it’s likely a skin growth called keratosis.

Keratosis is a growth of keratin on the skin or on mucous membranes stemming from keratinocytes, the prominent cell type in the epidermis.

Keratin filaments in our cells are essential for growing hair, skin, and nails.

As keratosis has different types, the dermatologist claims Trump has one of two things. The first option is seborrheic keratosis: a benign, non-cancerous type of skin growth that’s kind of like a brown barnacle, Suozzi said. This kind of growth is sometimes referred to as a “senile wart”.

“Those are kind of random,” Suozzi said. “You’re partly genetically predisposed to them, and they’re also worse in patients that have more sun damage.”

In case it is a seborrheic barnacle, there’s no real need to worry.

The other option is an actinic keratosis, Suozzi said, which can cause cancer in rare cases. This typically develops in fair-skinned people over the age of 30 who’ve seen a lot of sun.

“The risk of any one of them becoming a skin cancer is pretty low,” Suozzi said. “Somewhere from one in 100 to one in 1,000.”

Keratosis is a fairly common problem, especially for people like Trump with fair skin and light eyes. One of the most common, effective ways to treat keratosis spots is to freeze them.

But the freezing treatment for keratosis spots doesn’t always work, and can leave that patch of skin lightened.