skin communicates messages about your youthfulness, your vibrancy, and your health. Face it: Skin sells.
FACTOID
We love exercise. But exercise for the face? That’s an idea whose time has not come. Exercising the facial muscles is a sure way to increase your wrinkles. The facial muscles pull on the skin to give you facial expressions. And the repetitive movements of the skin, over the years, combined with the normal thinning of the collagen and elastin of the dermis, will eventually crack the skin, causing wrinkling. Botox is the reverse of exercise; it paralyzes muscles and lessens wrinkles.
Safari Secrets:
Lessons from the animal kingdom
The reason why there are butterfly collectors and not moth collectors? The colors of moths are determined by scales that are shed, so they don’t keep their colors in the box, only in life—just like humans. The colors of a butterfly’s wings are never lost.
Your Skin: Let’s Flesh a Few Things Out
Funny, whenever we say something’s skin deep, we mean that it has about as much depth as a puddle. But that’s hardly the case with skin—it’s an amazing and complex organ that extends much deeper than the part we can actually see and touch. Your skin is the biggest and heaviest organ of your body, making up 15 percent of your body weight and covering 12 to 20 square feet. The composition: 70 percent water, 25 percent protein, and less than 5 percent fats. The obvious role of skin is to protect and to package. It protects our blood, organs, and bones from what’s outside, and it also packages our body neatly together so we’re not blobby organisms that leave trails of blood and bits of tissue everywhere we go.
And skin does more than serve as our anatomical casing. Skin also helps us with healing. How? Touching in that loving way reduces levels of the stress chemical cortisol and increases levels of the feel-good chemical oxytocin. And touching in that special way (massaging and caressing, not the touch of a slugger’s right hand) also stimulates the vagus nerve, which runs up to the brain to improve the health of our whole body.
So here’s how your skin works. While serving as an obvious barrier to the millions of chemicals and germs that want to invade your body, it also has a big sensory function. Deep in the skin, follicles grow hairs that can sense before your skin is actually touched. Eyelashes, for example, prompt the eyelid (through great nerve connections) to involuntarily close to protect the eye before you even know you’re in danger and to quickly flick off bugs before they bite.
Besides sprouting up hairs that sense things, your skin lubricates itself with oils we call sebum produced by sebaceous glands and also absorbs certain medications and hormones. But it can also absorb things, such as toxins, that you don’t necessarily want. And ultraviolet light can turn your own skin against itself by creating those much-talked-about damaging free radicals, not to mention changing your DNA (and usually not for the better).
Like many structures in your body (including your blood vessels), your skin has several components (see Figure 1.1).
FACTOID
We can generate as much as a gallon of sweat in two hours, so we don’t have to pant like a dog (dogs don’t sweat). Also, unlike dogs, most of us don’t shed our furry coat, but we do lose nine pounds of skin a year. That’s a lot of dust.
Epidermis: Serving as the body’s primary barrier against the outside world, the epidermis is less than a millimeter thick. Your skin is your raincoat, keeping your insides dry and letting you swim without swelling. Your epidermis is so well designed that only the right-size molecules can get through. The cool thing about your skin is that it renews itself every six to eight weeks. How? Dead cells from the epidermis continually slough off and are replaced by new ones from below (that’s one major way you get dust in your home—the sloughing off of skin). Your epidermis largely determines how fresh your skin looks—as well as how well it works in terms of absorbing and retaining moisture.
Dermis: The thickest of your skin layers, the dermis is what actually holds you together.* It’s your leather. The dermis is made up of cells called fibroblasts, which make collagen and elastin, proteins that give the dermis its strength and allow it to be stretched. Dotting the dermis are hair follicles, sweat glands, and sebaceous glands, which produce the oily sebum that lubricates your skin and hair. This sebum is really a mixed blessing; while it helps keep bacteria under control, it also attracts insects. Finally, the dermis contains tiny blood vessels (to nourish the skin) and lymph nodes (to protect it from toxins). Subcutaneous tissue: This innermost layer is made up primarily of fat and acts as a shock absorber and heat insulator for your body (many mammals, by the way, don’t have this because their fur does the same job).
Figure 1.1 Flesh Beating UV radiation damages the skin by weakening elastic collagen fibers and by preventing stem cells from rejuvenating the injured area. It also causes free radicals to damage the DNA, which can lead to cancer. UV-C is blocked by ozone, UV-B penetrates the epidermis, and UV-A goes even deeper to the dermis.
The Skinny: How Your Skin Works
Your skin can do more than get you arrested. It’s able to do many things—some good and some we’d rather live without.
IT SWEATS: In a way, our skin acts as our third kidney, detoxifying our bodies. When we exert ourselves, not only do we sweat to cool our bodies, we also increase blood flow, which releases toxins. Though it may not be so great on silk blouses and stair climbers, sweating is something you need to do regularly—not just because of the cardiovascular and fat-frying benefits of exercise, but also because of its body-cleansing function.
IT TANS AND BURNS: Exposure to sun causes an immediate release of stored melanin and stimulates the cells designed to protect you from too much sun, the melanocytes, to produce a protective pigment, melanin. But that process takes several days, by which time you have left the beach with Santa-suit-colored flesh. The sun, unbuffered by melanin, is your skin’s cancer-causing deep fryer.
FACTOID
If stretch marks make your skin look like a highway atlas, the answer isn’t to try to cover them up with creams or makeup. They actually could be a road map to something more serious that’s going on inside your body. First, you need to make sure that your adrenal gland isn’t making too many steroids (that could be a sign of Cushing’s disease). If the marks are less than a year old and still have a purplish hue, you can have them lasered to lighten them, but other than that, only surgery can remove them.
Stop the Burning
Some burns are preventable (sideburns and sunburns), some burns are accidental (darn curling iron!), and some burns are downright dumb (leave the fireworks to the pros, smart guy). No matter what the cause, you can take steps to soothe the pain—and prevent scarring or further damage. First, you’ll want to cool the burn with water or ice as soon as you can to reduce the prostaglandin response and limit the damage. Clean the area with water and a simple soap such as Ivory, Neutrogena, Dove, or Cetaphil to remove dirt and bacteria, and don’t pop any blisters that form. For the small blisters, apply a sterile moisturizer like bacitracin or Neosporin twice a day and leave them intact. They serve as the ideal sterile biologic dressing over the nascent skin that is quickly growing to cover the injured area. Scarring is always worse if the growth of this new skin is hindered. Cover blisters with a fine gauze like Vaseline gauze or Adaptic. The small blisters will dry up and flake off within two weeks.
Note: If the burn
