Feed Your Face: Younger, Smoother Skin and a Beautiful Body in 28 Delicious Days

FEED YOUR FACEGetting to Know Your Skin

A few years ago a young father of three came to my office with what he thought was a rash. He was a strong, sturdy guy—a construction worker—with no health problems to speak of except for this persistent itch that was keeping him up at night. His pharmacist gave him oatmeal baths, his wife bought him all sorts of lotions and creams, but nothing worked. Even as we talked, he scratched and scratched and scratched, but when I examined him, I couldn't find any rash. All the marks on his skin were self-inflicted, left over from his fingernails digging into his flesh.

There are all sorts of reasons for why someone might develop "itching of unknown cause," but it's a long and scary list (think liver problems, cancer, etc.). I didn't want to freak the poor guy out—at least not without knowing anything for sure—so we took some blood, I wrote a prescription for a soothing cream, and we sent his sample out for tests.

The next day I got a call from the lab. This was not good news: The lab never calls unless something is seriously wrong. As fate would have it, the young man was in full kidney failure and very, very sick. I referred him to an internist who put him on dialysis that very same day. And all he had was an itch.

It is not my intention to scare the living daylights out of you here but, rather, to point out a simple fact: Your skin is important. It's not just what keeps your insides in; how it looks is an indicator of your overall health, and it's often the first (and sometimes the only) sign of serious illness elsewhere in the body. If your liver is in bad shape, you'll get jaundice (you'll turn yellow). Pale skin and hair loss are often the first signs of anemia. People with lung disease can appear pale and sallow (because they're not getting enough oxygen to the skin). Crash dieters can look gaunt, as if their skin were sagging. In fact, every time you visit a doctor—any doctor, not just a dermatologist—he or she checks out your skin as part of the overall examination. Taking care of your skin is a big part of keeping your whole body healthy.

Here's the good news: Getting beautiful, healthy skin doesn't have to be time-consuming, expensive, or intimidating. You don't have to forgo getting a great tan. You don't have to stop wearing makeup. And you definitely don't have to keep Olga, the Russian facialist, on speed dial. But before we can talk about looking good, we have to talk about how the skin—your body's largest organ—works. Here's a look at what's really going on in there.

It's Aliiive! Your Skin is Living and Breathing

Just as your digestive system takes in food, processes nutrients, and gets rid of waste, your skin takes in nutrients from the blood, produces by-products (such as oil and dead skin cells), and sends what it doesn't need back into the bloodstream. For this reason we say it has its own metabolism, and how it functions is directly related to the fuel it receives (i.e., the food you eat).

Your skin is also what we call a microbiome; it's teeming with microorganisms, most of which are invisible to the naked eye. Even when you think you're clean (like right after a long, hot shower), you still have bacteria, fungus, yeast, and parasites living on and in your skin (gross, but true). They're supposed to be there, of course, and normally they all live in harmony, but when that delicate balance gets disturbed (by hormone fluctuations or changes in your diet, for example), one component overgrows, and your skin reacts. Rosacea, acne, and many rashes are caused, at least in part, by bacterial overgrowth or imbalance.

Hey, Dr. Wu

Q: So, how many skin-care products do I really need?

A: Two to three products—tops—should do the trick: a cleanser, sunscreen (typically in the form of a moisturizer with SPF), and a treatment of some kind in the evening, depending on your particular needs.

Over the years I've come to realize that skin care basics often confuse people the most. In fact, the majority of questions I receive from my online newsletter are about the simple stuff, such as the proper way to wash one's face or what to look for in a moisturizer. That's why I'll be sharing tips and tricks, as well as specific product recommendations, along the way.

Is it Hot in Here? Your Skin Controls Your Core Temperature

The skin maintains your core temperature of 98.6°F by controlling the amount of water that evaporates from your body. The evaporation of water from the skin is what cools you down. If it's very cold outside, you won't sweat as much because your body is conserving heat. On the flip side, if it's really warm outside, your body increases perspiration (obviously); as the water evaporates from your skin, you cool off. That's why people who live in dry heat don't feel as uncomfortable as people who live in more humid parts of the country. It could be 110 degrees outside, but if you're in, say, Arizona, the sweat on your skin will evaporate quickly because the air is dry. On the other hand, if you're in south Florida, it might be only 85 degrees, but there's already so much water in the air that the sweat evaporates much more slowly. It's like being in a steam shower—sticky and uncomfortable.

Were you to lose large areas of your skin—in a fire, for example—you'd also lose your ability to regulate your internal temperature. That's why burn victims have to be wrapped from head to toe and kept in warm beds. There's a huge risk of developing hypothermia when you can't prevent water loss or hold in heat. That is also why a serious sunburn (as in second degree or worse, when the skin blisters and peels off) can make you shiver and shake.

Skin Enemy #1: Inflammation

Your skin is an important part of the immune system—it is the first line of defense against outside "intruders" such as bacteria, allergens, and foreign objects (like dirt or splinters). When the skin is breached by one of those unwelcome guests, your body sends a rush of investigative immune cells to the affected area, triggering inflammation in the form of redness, heat, and swelling. That is why your eyes will puff up during allergy season, why you'll spike a fever if you have an infection. Typically, your body's natural immune response is temporary. Once you've recovered from any trauma, infection, or allergy, the associated redness and swelling will subside. For some people with imbalanced immune systems, however, that inflammation never really dies down; and the longer their body stays inflamed, the worse it is for their health.

Recently, chronic inflammation has become a hot topic in the medical world as more and more studies suggest that it's a root cause of conditions ranging from heart disease, cancer, and Alzheimer's to osteoporosis and other diseases associated with aging. Doctors now think that cardiovascular disease, for example, is caused in part by inflammation of the arteries, not just an accumulation of plaque. Long-term inflammation can damage healthy tissue, including your arteries (leading to atherosclerosis, or hardening of the arteries) and your joints (causing arthritis).

Inflammation is also a hallmark of skin conditions such as acne, eczema, psoriasis, rashes, and even sunburn. And while you might be tempted to think of acne as a form of infection (due to the pus), it is really your body's inflammatory response that produces redness, swelling, and whiteheads. In fact, a number of the antibiotics we use to treat acne are prescribed not for their ability to kill bacteria (the dosage is too low) but to reduce inflammation.

Learning how to manage and prevent inflammation is important for your overall health and is essential for maintaining the health of your skin. And one of the most effective tools in regulating and preventing inflammation is—you guessed it—eating the right foods. Altering your diet can help modulate the effects of inflammatory conditions such as eczema and acne as well as help slow the signs of aging. Keep reading. I'll show you how.

Your Skin is the Body's Main Source of Vitamin D

Back in the early 1900s a childhood disease called rickets, which leads to softening of the bones and skeletal deformations, was a growing national problem. Hundreds of thousands of children, particularly in the industrialized cities of the Northeast, suffered from bowed legs and weak, crumbling teeth. It wasn't until the 1930s, when the government started fortifying milk with vitamin D, that rickets all but disappeared.

Vitamin D is extremely important not only in preventing rickets in children (and osteoporosis in adults) but for bone health in general (it helps your body absorb calcium from the GI tract) as well as muscle function and reduction of inflammation. Studies show that vitamin D may even help prevent both breast and skin cancer; however, there are only a few ways to get vitamin D in the body. Some foods (including milk, egg yolks, salmon, and tuna) and nutritional supplements are two ways, but the largest source by far comes from a chemical reaction that begins the minute we walk outside.

Our skin naturally contains something called 7-dehydrocholesterol. When exposed to UVB rays from the sun, this organic molecule magically becomes—drum roll, please—vitamin D. Here is where things get complicated: A small but vocal group of doctors are convinced that vitamin D deficiency is fast becoming a public health epidemic again. (Indeed, some studies have shown that rickets, once considered a thing of the past, is on the rise.) One possible cause? A lack of direct sun exposure. The idea is that once we all got hip to the dangers of UV light (burning, premature aging, age spots, and skin cancer, to name a few), we stopped getting enough sun to produce adequate levels of vitamin D. That's a pretty controversial notion.

Before you slather on the baby oil, you should know that studies have shown that regular use of sunscreen does not significantly interfere with your body's ability to produce vitamin D. There is also no consensus as to what constitutes an adequate level of vitamin D, and the ideal amount may be different for different people. If you're concerned about getting enough, talk to your doctor about taking a supplement. But please, don't sit in the sun unprotected. Also, skip the tanning beds altogether, which emit mostly UVA rays anyway. (Remember, it's UVB rays that produce vitamin D.)

Skin Enemy #2: UV Radiation

We all know that too much sun can make your skin look like a vintage leather handbag or, worse, like Magda, the scary lady from the Ben Stiller/Cameron Diaz hit There's Something About Mary. But UV damage is more than just aesthetic. The sun's rays penetrate deep into the skin—all the way down to your DNA. Recent research shows that UV radiation can temporarily alter the function of white blood cells, meaning that even mild sunburns can suppress the immune functions of the skin. And if you've had sunburns in the past (who hasn't?), you're already at greater risk of developing melanoma, the deadliest type of skin cancer. That's why both the American Academy of Dermatology and the American Medical Association recommend staying out of the sun between 11 AM and 2 PM as well as wearing sunscreen and protective clothing when you're outdoors. It is also why most dermatologists equate sunbathing with devil worship. But I'll let you in on a little secret: I like being tan. Having some color makes me feel taller, thinner, healthier, and more beautiful. UV light can even guard against seasonal affective disorder (SAD), better known as the winter blues.

That is why I'm not going to tell you to stay indoors during the day or to wear long sleeves in the summer. In my experience the less realistic the advice, the less likely you are to follow it. For example, when my osteopath told me the only answer to chronic hip pain was to ditch my high heels for flats, I told her to forget it. There's no way I'm giving up my four-inch platforms. (Besides, my husband is 6'2", and I want to be able to look him in the eye!)

The thing is, you don't have to wear a burka to be safe in the sun. Certain foods—green tea and tomatoes in particular—have been shown to boost your skin's ability to fight UV rays and sunburn, so incorporating them into your diet, especially before you hit the beach or spend an afternoon on the tennis courts, can improve the protection you'll get from sunscreen alone. For much more info on sun damage, UV-fighting foods, and even fake tanning tips, turn to .

Your Hair and Nails Are Part of the Skin

You may not have realized it, but your hair and nails are part of the skin, so problems ranging from dandruff to hair loss to ingrown nails should be treated by a dermatologist. More often than not, women will seek the advice of a stylist when they notice thinning hair (and end up spending a fortune on products like Kérastase, an uber-expensive professional-grade product line). Or, when they notice thickened or splitting nails, they'll head directly to a nail salon. (A manicurist might be great with acrylics, but could unknowingly file down the fungus and spread it to other clients. Gross.)

Just as your diet can affect the appearance and health of the skin, what you eat can affect the health of your hair and the look of your manicure. There's more: If your body is deprived of certain nutrients (as a result of, say, crash dieting), it bypasses "nonessential" functions such as making hair and nails and directs what nutrients it does receive to more important organs, like your heart and brain. That is why it's so important to feed your body the right kinds of foods—unless, of course, you want to look like Mr. Clean. (Get it? He's bald!)

Your Skin Is a Reflection of Yourself

Perhaps the most important function of the skin is also the easiest to understand. I mean, hell-o! The skin is your body's largest organ. It's what your man touches when he caresses your leg or kisses your neck. It's the first (and sometimes only) thing we see when we look in the mirror.

Waking up with clear, smooth skin is like having a good hair day: It can make you feel confident and sexy. But wrinkles, blemishes, and sun spots can have the opposite effect: They can sabotage your self-esteem. That's why my role as a dermatologist is not unlike being a therapist. Many of my patients come in down on themselves, depressed about how they look. Whether it's the teenager with acne who is slumped and slouched and has her hair in her eyes or the woman with sun damage who is too embarrassed to wear a strapless dress because of the blotches on her chest, my message has always been the same: You don't have to live with skin you don't like.

FROM THE FILES OF Dr. Wu

Patient: Anna Liza

Skin Concern: Mild to severe acne

Food Sensitivity: Dairy

In Anna Liza's Words: As a busy financial executive I spend a lot of time in airports as well as entertaining clients across the country. While I usually experience mild breakouts associated with my menstrual cycle, my acne always gets worse when I travel. I also had been suffering from chronic pain in my lower abdomen for five long years. I had seen three different specialists, each of whom ordered a battery of tests, but none could pinpoint the problem.

When Dr. Wu first gave me the Feed Your Face Diet—and told me to avoid dairy products—I balked. My husband is French, and we both enjoy wine and cheese. Still, I figured it was worth a try. Ten days later my skin was definitely calmer, and I'd had no new breakouts. One month later my skin was smooth and clear, and the painful cysts were gone completely. But what really surprised me was that my abdominal pain was gone, too. I had never put two and two together, never guessed that my unexplained stomach pains had anything to do with my skin!

I still travel a lot, and when I'm busy wining and dining colleagues or clients, it's always tempting to have what everyone else is having. But now that I know dairy aggravates my acne (not to mention my stomach), I don't mind skipping the cheese course or passing on creamy desserts. For me that's a small price to pay for clear skin.

Dr. Wu's Diagnosis: I wasn't at all surprised when Anna Liza told me that her breakouts worsened after traveling. From the stress of running to catch a connecting flight to the recirculated (and germ-filled) air in a crowded cabin and the subpar food, it's not at all unusual to experience skin flare-ups of all kinds, from acne to eczema, when you spend a lot of time on the go. Nor was I surprised when her skin cleared after eliminating dairy from her diet. Dairy products often aggravate acne in women of all ages. It's my stance that we all eat too much dairy anyway, even those of us who don't have acne. More on that in .

Putting It All Together: The Skinny on Your Skin

By now you realize that your skin is more than just something to put makeup on. And that's great, because understanding how skin functions is an important step in learning to care for it. Let's wrap up this chapter with a quick rundown of your skin's basic anatomy. For starters, you may think of your skin as having a single layer, but it's actually made of three layers, each containing several different types of cells:

LAYER ONE: The Epidermis

The outermost layer of the skin is called the epidermis. (You can think of it as the peel of an orange.) It, too, is divided into multiple layers.

The bottom part of the epidermis is called the basal layer, and it consists of two types of cells: melanocytes, which give your skin its pigment (they're what determine if you're fair like Nicole Kidman or mahogany like Naomi Campbell) and keratinocytes, which are actively growing and rapidly dividing cells that make keratin.

Unlike your heart, brain, and other organs, your skin is constantly renewing itself. As the active living skin cells in the basal layer of the epidermis divide and multiply, the older cells get more and more crowded. They start looking for room to spread out, moving closer and closer to the skin's surface in the process. Along the way they're busy making keratin, a tough-as-nails protein that protects the outermost layers of the skin. But this must be exhausting work, because before those busy, crowded cells ever make it to the surface, they die. That top layer of dead skin cells, which is what you touch when you touch your skin, is called the stratum corneum, and it's the thickest in accident-prone areas of the body, such as the knees, elbows, and soles of the feet. Because dead skin cells contain little to no water, this top layer is prone to drying out, chapping, and even cracking, particularly in the winter months (which is why your heels may crack and your elbows and knees can look ashy).

As more and more new cells rise to the top of the epidermis, they push off the older dead cells. This is your body's natural way of exfoliating. Supporting this process (by using a body scrub or a pumice stone as well as by eating foods that fuel keratin production) will encourage new cells to come in, keeping your skin looking pink and rosy as opposed to dry and crusty.

Did You Know...

There are no blood vessels in the epidermis, so the active living cells (the keratinocytes) depend on oxygen and nutrients diffusing up from the blood vessels located in the deeper layers of the skin below. Cigarette smoking and some medications constrict these blood vessels, however, allowing less oxygen and fewer nutrients to flow up to the epidermis. The result is skin that looks pale and sallow.

LAYER TWO: The Dermis

The second layer of your skin (which you can think of as the white part of an orange rind, the stuff between the peel and the fleshy meat) is called the dermis, and it contains connective tissue—collagen, elastic tissue, and hyaluronic acid—that gives the skin support and structure.

Collagen

Collagen functions like the beams in your house or the boning in a couture gown: It gives your skin its support. There are more than twenty types of collagen in multiple organs throughout the body, but the vast majority of collagen in our skin is Type I, which is the strongest. In fact, gram for gram, Type I collagen is stronger than steel.

We're all born with plenty of collagen, and at first our skin cells are busy pumping out more and more of it (which is why children have firm, resilient skin). As time goes by, however, collagen production slows, so our skin gets thinner, less resilient, and more likely to wrinkle. Eating the right collagen-boosting foods can help fight this process and keep your skin looking younger and smoother.

Don't Fall for It: COLLAGEN CREAMS

Creams that promise to fill fine lines and wrinkles with collagen are pretty much bogus because the collagen molecule is too large to actually penetrate the skin; instead, it just sits on the surface. (That's why injectable fillers such as Restylane and Juvéderm were created.) Collagen creams can make decent moisturizers, and that's good (dry skin can make fine lines more pronounced), but they won't get rid of your wrinkles.

Elastic Tissue

Pinch a piece of your skin. It snaps back in place when you let go, right? That's your elastic tissue at work. Made of a protein called elastin, elastic tissue is what keeps your skin flexible and allows it to hold its shape. As we age, elastic fibers begin to break apart, so your skin gradually loses its bounce-back ability. This is why smile lines slowly become deep creases that stay put even when you stop smiling. Over time you might notice that sleep creases take longer to go away, too (because, apparently, your face can freeze like that). Prolonged sun exposure can also damage elastic fibers, which is why sun-damaged skin sags prematurely. And if the skin stretches too fast (such as during pregnancy or a growth spurt), the elastic fibers snap—not unlike what happens when you pull too hard on a rubber band. That's when you wind up with stretch marks. You can help prevent snapping and sagging, however, by choosing foods that will supply your body with the building blocks of strong elastic tissue.

Our skin's connective tissue (i.e., our collagen and elastin) is also partly responsible for the appearance of cellulite, the cottage-cheese-like dimpling that you might notice on your upper thighs and derriere. That's because collagen and elastin fibers sit perpendicular to the dermis. When fat expands (when you gain weight), it causes those fibers to tug on the underside of the skin, creating dimples. Women are more prone to developing cellulite than men because male connective tissue is assembled in a crisscross pattern, at a 45-degree angle to the dermis (so any dimpling appears less pronounced). Women also tend to have a thicker fat layer than men, which is more likely to bulge through the connective tissue (lucky us). Circulation problems may also contribute to cellulite in a woman's legs, hips, butt, and belly.

A CURE FOR CELLULITE?

Many of my more famous patients indulge in anticellulite Endermologie treatments (which incorporate suction and massage to smooth the skin) before they have to film a bikini scene or walk the red carpet in a slinky gown. (Imagine having two rolling pins that are connected to a vacuum hose rolled over your hips and thighs for forty-five minutes, and you'll get the picture.)

In the, ahem, interest of science, I decided to try Endermologie myself. (Did I mention this involves wearing a skintight head-to-toe bodysuit?) Although my skin did feel a bit smoother afterward, I can't be sure how much the treatments actually helped because once I knew that some stranger was going to be working on my thighs, I really started watching what I ate in between appointments. There is some evidence that it works, though—at least temporarily. A recent study showed that women who received the treatment twice a week for fifteen sessions lost inches, but the results are best immediately following the procedure. This may reflect a temporary improvement in circulation or a swelling of the skin (which would make lumps less obvious) rather than a real "loss" of cellulite.

You can produce a similar effect by doing your own vigorous massage at home in the shower (without the humiliation of the unitard). Try The Body Shop's Cellulite Massager to improve circulation and smooth your skin. Then towel off and apply a cellulite cream such as Bliss's fatgirlslim or RéVive's Cellulite Erasure. Both contain caffeine, which has been shown to break down fat cells.

Hyaluronic Acid

Hyaluronic acid is a natural sugar that binds water molecules together to keep your skin plump and hydrated. It is also the "jelly" in your eyeball as well as a lubricant in your joints. The popular wrinkle fillers Juvéderm and Restylane use synthetic hyaluronic acid as an active ingredient.

A side from connective tissue and hyaluronic acid, the dermis is also where you'll find the sebaceous glands (or oil glands)—concentrated primarily on your face, chest, back, and scalp—that secrete sebum (oil), your body's natural moisturizer. Sebum is what keeps your skin soft, supple, and waterproof. (After all, you won't melt if you walk in the rain or take a dip in the ocean, right?) Too much oil, however, can make your skin shiny and your makeup smear.

There are a number of reasons for why the sebaceous glands might go into overdrive, including stress, hormonal fluctuations associated with puberty and your menstrual cycle, and even certain foods. Overactive glands pump out lots and lots of oil, causing the pores to enlarge (which is why people with oily skin tend to have bigger pores). Excess oil on the scalp can make your hair feel greasy as well as predispose you to yeast overgrowth and dandruff. But choose the right foods, and you can modulate your skin's sebum production and control such conditions as acne and dandruff.

Did You Know...

When you get inked, tattoo pigment is injected past the top layers of the skin and deep into the dermis. Since this part of the skin is constantly being patrolled for "invaders," and tattoo ink is technically a foreign substance (biologically speaking, it's not really supposed to be there), immune cells called macrophages attempt to gobble it up and digest it. That's why tattoos fade over time.

Skin Enemy #3: Free Radicals

You've heard about them before in countless skin-care ads and magazine articles, but what the hell are free radicals and why should we care about them?

Without getting too technical (for those of you who aren't science nerds), free radicals are atoms or molecules with an unpaired electron in their outermost shell. This makes them highly unstable and prone to undergo spontaneous chemical reactions in the hope of "stealing" an extra electron from a neighboring molecule.

Let's try an analogy: A free radical is not unlike a car with three wheels—you need the fourth to drive in a straight line and to stop you from wobbling and veering off course. But if you steal a tire from someone else's car, now they're left with an unstable ride. Likewise, when a free radical steals an electron from, say, a collagen or DNA molecule, those cells no longer function as intended, and that can have serious consequences. For example, it's believed that some forms of cancer are caused by chemical reactions between free radicals and DNA. According to the "free radical theory of aging," long-term free radical damage is the cause of most age-related diseases, including arthritis, Alzheimer's, and atherosclerosis. And in the skin, free radical damage causes a breakdown of collagen and elastin, leading to wrinkles, sagging, and discoloration. Put simply, free radicals are the reason that our bodies start to break down over time.

Free radicals exist all around us—they're even natural by-products of the body's metabolism, the network of chemical reactions that keeps us alive. But they're also found in abundance in pollution, toxins, pesticides, and cigarette smoke. In addition, they are produced when UV rays interact with the skin. Typically, your body can neutralize most free radical damage on its own, but if you're bombarded by such factors as UV light, pollution, and secondhand smoke, you'll overwhelm that innate ability. The net result is a breakdown of healthy cells and a face that looks old and tired.

LAYER THREE: Subcutaneous Tissue, a.k.a. the Fat Layer

Not only are we born with beautiful skin, but we're also born with a nice, thick layer of fat right underneath it. (Continuing with the orange analogy, we're talking about the meat of the fruit now, the part you eat.) This subcutaneous fat, which looks like the thick yellow fat you might find under chicken skin, provides a barrier between the dermis and your muscle tissue; it insulates the body and gives your face its contours. (It's why babies and children have such soft, curvy cheeks.) As we grow up, we lose some of that fat, and our faces sort of deflate; the cheeks hollow out, and the lips flatten. So where does all this fat go? Instead of gravitating to the cleavage—where we could use it—it migrates down to the belly and butt. Go figure.

Hey, Dr. Wu

Q: My dermatologist says wearing makeup can cause breakouts because it clogs the pores and doesn't let your skin "breathe." Is makeup really bad for my skin?

A: Good news, girls. Breakouts are typically caused by bacteria, hormonal fluctuations, and the foods you eat—not by Laura Mercier. In fact, some makeup can even be good for you. Certain cosmetics can provide SPF protection, which is great for those of us who sometimes forget to put on sunscreen. (You know who you are.) Wearing makeup may also remind you not to touch your face as often, cutting down on the transfer of germs from your hands. And as long as you're choosing the right makeup for your skin, it shouldn't make you break out. If you have oily skin, large pores, or acne-prone skin, look for a water-based makeup that is noncomedogenic. And if you're still breaking out, don't worry. In you'll learn more about acne and how to fight it with skin-friendly foods.

FEED YOUR FACE Copyright © 2011 by Jessica Wu, M.D.