Gone are the days when our grandmothers slathered their faces with Vaseline and Crisco, hoping the fats would keep their skin firm and dewy. Too bad they didn't know that cold-pressed, plant-based oils are far more effective for moisturizing skin than industrial-strength, petroleum-based products, especially in the winter. "Skin tends to lose moisture in the cold, but heaters inside cars and houses also dry the skin tremendously," says Nadia Arora, ND, of Washington, D.C. And because humidifying oils can be just as beneficial, if not more so, when ingested, it's as important to moisturize from the inside out as the outside in. Here's how.