It's the main ingredient in most beauty products and a crucial element of every skin care regimen ... but I still encounter lots of misconceptions when it comes to plain ol' water! 

    Yes, water is essential to all of our biological processes. When it comes to skin, H20 is necessary for the proper functioning of enzymes that enable skin to continually replace itself and slough off old, dead cells. And yes, if the body is severely dehydrated, you will see changes in your skin. But true dehydration is very different from the occasional need for a tall glass of water.

    In the vast majority of cases, then, dehydrated skin is not indicative of a dehydrated body - and drinking more water will not have a significant impact on your skin's hydration. Make no mistake: As a doctor (and a human being!), I'm a big fan of water and advocate drinking plenty of it. But if you're experiencing dry skin - and more of us will be as the weather turns cooler and humidity drops in many parts of the world - the only way to get relief is to strengthen your skin barrier.

    So, what's the skin barrier? That's the layer of skin - right in the middle of the epidermis - that's rich in lipids (a.k.a. fats) like fatty acids, cholesterol, and ceramides. When it's healthy, it is responsible for keeping moisture in your skin, and irritants out.

    But when this barrier is compromised, your skin loses water to the environment, resulting in dry skin, and is also more susceptible to allergic reactions and irritation. That's also why you may feel plagued by dull skin during the winter: When the skin barrier is disrupted, its lipids aren't holding your skin cells together effectively. As a result, cells' edges begin to curl up, resulting in dry skin's rough, lifeless appearance.

    The best way to tackle dry skin, then, is to help bolster the skin barrier so it can do its job and retain moisture. In fact, you can find the same lipids that are naturally present in your skin barrier in many moisturizers - fatty acids (like stearic acid), cholesterol, and ceramides are readily available in many creams and lotions. Glycerin, another rich moisturizer, is also easy to find. Best of all, these top-notch ingredients are affordable, and you'll find them in the aisles of your very own drugstore.

    My favorites? For your face, look for the Dove ProAge moisturizers. And if you're in the market for a bit of a splurge, Atopalm MLE Cream is a wonderful option for dry, sensitive skin. For the body, I love Cera Ve Moisturizing Cream, Dove ProAge Cream Oil Lotion, and Vaseline Intensive Rescue Moisture Locking Lotion.

    Wishing you great skin!

    水是多數美容用品的主要成分，是所有皮膚護理方案的關鍵要素。。。但說到純粹的水，我還是遇到了不少錯誤的想法。

    不錯，水對我們所有的生命活動都是至關重要的。說到皮膚，水對能促使皮膚不斷新陳代謝的酶來說，是必不可少的。如果身體嚴重脫水，皮膚就會出現變化。但真正的脫水跟偶爾要來一大杯水的情況多有不同。

    絕大多數情況下，皮膚脫水不代表身體脫水----而且多喝水并不能明顯潤澤你的皮膚。可別犯錯了：作為一個醫(yī)生（作為人類！），我是挺愛喝水的，也提倡多喝。但如果你皮膚干燥----天氣變冷濕氣降臨的時候全球大部分地區(qū)的大部分人都會如此----唯一的緩解方法是筑牢皮膚防線。

    那么，皮膚防線是什么呢？是夾在表皮層中間的一層皮，富含脂肪酸，膽固醇和神經酰胺等類脂物（也可以叫脂肪），在健康狀態(tài)下負責鎖住水份，使肌膚免受外界刺激。

    如果防線崩潰，皮膚就因失水而變得干燥，易過敏，易受刺激。這就是為什么你會在冬天因皮膚干燥而煩惱：皮膚防線瓦解，類脂物無法有效將皮膚細胞結為一體。因此，表皮細胞的邊緣開始卷起，使得干燥皮膚看上去粗糙無生氣。

    解決皮膚干燥問題的最好方法還是筑牢皮膚防線，使之能正常運作，鎖住水分。實際上，許多潤膚膏包含的類脂物與皮膚防線自有的沒什么區(qū)別----脂肪酸（如硬脂酸），膽固醇和神經酰胺在很多洗面奶和化妝水里都有。另一種較貴的潤膚霜甘油，也比較好找。最喜人的是，這些高級成分都是買得起的，你隨便在哪個藥房都可以找到。

    我的收藏？臉部護理用Dove ProAge潤膚霜。如果你想在周圍炫一下，Atopalm MLE Cream 是個好選擇，專為干燥敏感皮膚而備。全身護理，我喜歡用Cera Ve 保濕霜, Dove ProAge Cream Oil Lotion, 和 Vaseline Intensive Rescue Moisture Locking Lotion

    愿你擁有美好肌膚！