Excerpt: Dr. Jessica Wu's 'The Feed Your Face Philosophy'

Feb. 2, 2011 — -- Dermatologist Dr. Jessica Wu explains how her diet improves your skin by eliminating blemishes and reducing wrinkles.

Read an excerpt from "The Feed Your Face Philosophy" below or click here to check out her website.

A few years ago a young father of three came to my office withwhat he thought was a rash. He was a strong, sturdy guy— a constructionworker— with no health problems to speak of except forthis per sis tent itch that was keeping him up at night. His pharmacistgave him oatmeal baths, his wife bought him all sorts of lotions andcreams, but nothing worked. Even as we talked, he scratched and scratchedand scratched, but when I examined him, I couldn't fi nd any rash. All themarks on his skin were self- infl icted, left over from his fi ngernails digginginto his flesh.

There are all sorts of reasons for why someone might develop "itching ofunknown 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 knowinganything for sure— so we took some blood, I wrote a prescription for asoothing 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 labnever calls unless something is seriously wrong. As fate would have it, theyoung man was in full kidney failure and very, very sick. I referred him toan internist who put him on dialysis that very same day. And all he had wasan 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 whatkeeps 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 elsewherein the body. If your liver is in bad shape, you'll get jaundice (you'llturn 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 notgetting enough oxygen to the skin). Crash dieters can look gaunt, as iftheir 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 theoverall examination. Taking care of your skin is a big part of keeping yourwhole body healthy.

Here's the good news: Getting beautiful, healthy skin doesn't have to betime- consuming, expensive, or intimidating. You don't have to forgo gettinga great tan. You don't have to stop wearing makeup. And you definitely don'thave to keep Olga, the Rus sian facialist, on speed dial. But before we cantalk about looking good, we have to talk about how the skin— your body'slargest 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 ridof 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 thebloodstream. For this reason we say it has its own metabolism, and how itfunctions 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 thinkyou'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'resupposed to be there, of course, and normally they all live in harmony, butwhen that delicate balance gets disturbed (by hormone fl uctuations orchanges in your diet, for example), one component overgrows, and your skinreacts. Rosacea, acne, and many rashes are caused, at least in part, by bacterialovergrowth 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 atreatment of some kind in the evening, depending on your particularneeds.

Over the years I've come to realize that skin care basicsoften confuse people the most. In fact, the majority ofquestions I receive from my online newsletter are aboutthe simple stuff, such as the proper way to wash one'sface or what to look for in a moisturizer. That's why I'll be sharingtips and tricks, as well as specifi c 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 theamount of water that evaporates from your body. The evaporation of waterfrom the skin is what cools you down. If it's very cold outside, you won'tsweat as much because your body is conserving heat. On the flip side, if it'sreally warm outside, your body increases perspiration (obviously); as the waterevaporates from your skin, you cool off. That's why people who live in dryheat don't feel as uncomfortable as people who live in more humid parts ofthe country. It could be 110 degrees outside, but if you're in, say, Arizona, thesweat on your skin will evaporate quickly because the air is dry. On the otherhand, if you're in south Florida, it might be only 85 degrees, but there's alreadyso 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'dalso lose your ability to regulate your internal temperature. That's why burnvictims have to be wrapped from head to toe and kept in warm beds. There'sa 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 orworse, 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 isthe fi rst line of defense against outside "intruders" such asbacteria, allergens, and foreign objects (like dirt or splinters).When the skin is breached by one of those unwelcomeguests, your body sends a rush of investigativeimmune cells to the affected area, triggering inflammationin the form of redness, heat, and swelling. That is whyyour eyes will puff up during allergy season, why you'll spike afever if you have an infection. Typically, your body's natural immuneresponse is temporary. Once you've recovered from any trauma, infection,or allergy, the associated redness and swelling will subside. For somepeople with imbalanced immune systems, however, that infl ammation neverreally dies down; and the longer their body stays inflamed, the worse it is fortheir health.

Recently, chronic inflammation has become a hot topic in the medicalworld as more and more studies suggest that it's a root cause of conditionsranging from heart disease, cancer, and Alzheimer's to osteoporosis andother diseases associated with aging. Doctors now think that cardiovasculardisease, for example, is caused in part by inflammation of the arteries, notjust an accumulation of plaque. Long- term inflammation can damagehealthy tissue, including your arteries (leading to atherosclerosis, or hardeningof 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 thinkof acne as a form of infection (due to the pus), it is really your body's inflammatoryresponse that produces redness, swelling, and whiteheads. In fact, a numberof the antibiotics we use to treat acne are prescribed not for their ability tokill bacteria (the dosage is too low) but to reduce inflammation.Learning how to manage and prevent infl ammation is important foryour overall health and is essential for maintaining the health of your skin.And one of the most eff ective tools in regulating and preventing infl ammationis— you guessed it— eating the right foods. Altering your diet can helpmodulate the eff ects of infl ammatory conditions such as eczema and acne aswell as help slow the signs of aging. Keep reading. I'll show you how.