Many try to hide it, but it's a fact of life that we wear our age on our skin. Wrinkles, lines, creases -- all the badges of existence that our outer selves are heir to eventually show their faces over time.
And among those reminders of piled-up birthdays are a number of spots and growths, some of them expected and recognizable, others that seem to pop up overnight or may seem mysterious.
"The skin manifests the most number of diseases of any organ," says Dr. An-Wen Chan, a dermatologist at Women's College Hospital in Toronto. "One factor is obviously time, so the older we are the more tendency there is to get certain types of benign and cancerous skin lesions."
Let's start with what is likely the most commonplace and easy for most people to identify.
As a child, you may have asked a grandparent or another older person, "What are those brown spots on your hands?"
"Liver spots" was probably the answer.
Liver or age spots are those flat, brownish blotches often seen on the back of the hands, although they can appear almost anywhere on the body.
"It really has nothing to do with the liver. They're just natural pigmentary changes that occur over time," explains Dr. David Swanson, a dermatologist at the Mayo Clinic in Scottsdale, Ariz. "You primarily see them on the back of the hands and the forearms, upper shoulders and back, and on the face."
These benign spots in the top layer of the skin usually occur in areas of the body repeatedly exposed to sunlight, but they can crop up in places that have rarely or never seen the sun, he says.
While many people ignore liver spots, viewing them as an inevitable part of the aging process, others would be happy to see them disappear to recapture a more youthful appearance.
There are, in fact, various creams that can fade age spots -- known as solar lentigos -- to make them less noticeable. The gold standard, says Swanson, is any topical agent that contains hydroquinone or tretinoin (Retin A).
A procedure that targets the spots with low-intensity pulse therapy, using different colours of the light spectrum than a laser does, can remove an age spot altogether, he says. "Then what happens is it gets scabby and peels off."
But because age spots are considered merely cosmetic aberrations, treatments to lighten or remove them are not covered by health insurance and consumers must pay out of pocket.
Another benign splotch that show up on the body's biggest organ is a cherry angioma, so-called because it looks like a red dot on the skin.
"They're a little collection of small blood vessels, which is why they're red," says Chan. "They can range from a pinpoint ... up to even half a centimetre."
"Some people seem to develop many more than others, and we don't have good evidence on what exactly causes them and who gets them," he says. "But they are very common."
Swanson calls cherry angiomas a natural and inevitable consequence of aging that virtually every person will develop.
"They're like a little mole of blood vessels, rather than a mole of pigment cells," he says, explaining that they primarily occur on the trunk and on the limbs close to the body. "Usually you'll see them on the inner aspect of a thigh or of the arms."
These red spots can also be removed, using an electric needle or a pinpoint laser beam, both of which seal off the blood vessels without harming surrounding tissue, says Chan.
Generally, cherry angiomas don't pose a problem, so their removal is considered a cosmetic procedure, notes Swanson. "Occasionally one will stick out a bit, rub against an article of clothing and people want them removed for that reason."
There is another class of skin growth, however, that may be a bit more unsightly and to the uninitiated have a more worrisome appearance.
Called seborrheic keratoses, these non-cancerous growths could be mistaken for moles.
"They have a stuck-on appearance, so they look like there's a waxy bump that's just kind of stuck on the skin," says Chan. "But there are many variations. Some of them are actually flat and never become raised; some of them are light brown, some are darker brown, some are very pale in colour and they can change slowly over time."
Keratoses, which grow from the epidermis or top layer of the skin, often develop a crusty surface, adds Swanson. "You tend to accumulate more and more over time. Some people have only a few of them and some people have a lot of them. But most people get at least one."
"You can get these absolutely anywhere. You can get these on any part of the body, except the palms and soles."
What causes these waxy-turned-crusty bumps to appear isn't well understood, and doctors aren't sure what role sun exposure might play in their development.
"The funny thing about seborrheic keratoses is they occur in areas where the sun doesn't shine frequently," says Swanson. "For instance, a common area where we see them is under the breast in females."
"You wouldn't think there would be that much sun acquired there. There may be other things that play a role. Friction? It's hard to say. There might just be areas of the body that simply are predisposed to getting these things."
Some people who have them want them taken off strictly for cosmetic reasons, but for others, keratoses can pop up in places that make them annoying.
"Sometimes they itch and sometimes they rub against friction areas -- bra straps, waistbands -- or one will sit on top of the crease of the ear so glasses will sit on it," Swanson says. Sometimes they even grow in an armpit.
Keratoses can be removed with tiny blasts of freezing liquid nitrogen or by scraping them off under local anesthetic. These procedures are usually designated as cosmetic and must be paid for by the patient.
Still, both Chan and Swanson stress that it's critical that patients with any of these age-related blotches and bumps check with their doctor to make sure they aren't cancerous lesions, especially the potentially deadly malignant melanoma.
"I would focus on the main danger signs," advises Chan, pointing to spots that are new or change quickly, those that look different from others or don't seem to heal when they should, constantly scabbing up or bleeding.
Or, as Swanson says of the various skin spots and growths, "if you see an ugly duckling, don't make the assumption it's the same as the other ones."
