Sweater - Lead
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Finding out how itchy a newly purchased knit actually is—despite how soft it felt in stores—might be the one downside to sweater weather. Unfortunately, it's an experience that plagues us more often than it should, which is why we made it our mission to find out how to go about shopping for itch-free knits. We turned to dermatologist Dr. Whitney Bowe to help us understand which textiles to look for and steer clear from. Buyer's remorse, no more.

Skin Sensitivity Level: High

Symptoms: Almost all sweaters drive you crazy (even wool and cashmere), you're miserable all day, and your skin becomes angry and itchy. You think you might have an allergic reaction.

Her Diagnosis: "Wool is notorious for creating a sensitive reaction. But if you have a reaction, it doesn't mean you're allergic—an allergic reaction usually happens a week after you wear the garment. If it happens the same day you're wearing the fabric, it's called irritant contact dermatitis, which can look like redness, itchiness, scaliness, or tiny bumps.

"Cotton and silk are very gentle on the skin, so I'd recommend a layer underneath—it'll save your skin dramatically. But if sensitivity still persists, then a synthetic sweater (anything made of polyester, rayon, elastane, viscose, nylon) is your best bet, though it doesn't hold heat as effectively. If your skin is still irritated with synthetic sweaters, you might be reacting to the dye, finish, or detergent residue."

Rx: Avoid wool altogether or limit contact with a layer of cotton or silk.

Skin Sensitivity Level: Medium

Symptoms: You find some sweaters itchy, but you'd rather do without the discomfort.

Her Diagnosis: "Cashmere can be a great option because it's soft and doesn't cause as much irritation as other wools. Cashmere doesn't contain lanolin, which is what most people find irritate their skin. Cashmeres come in plys—two plys tend to be finer.

"Another factor that could cause irritation is occlusion. Tight fitting fabrics are more likely to create friction and generate sweat, which can aggravate skin even more. Even if you're sweating for just five minutes, you can be itchy for the rest of the day."

Rx: Shop for gentler fabrics, like cashmere, and silhouettes that are more breathable and loose.

Skin Sensitivity Level: Low

Symptoms: Your discomfort level is tolerable—you can feel it, but it's not completely unbearable.

Her Diagnosis: "Some wools are more abrasive than others. Merino and lambswool tend to be gentler, while Shetland is made of a coarser fiber and mohair. Just as a rule of thumb, look to more upscale brands—the more expensive it is, often the gentler the wool is, which has to do with the materials that are sourced and the manufacturing process.

"Anytime you can dilute the percentage of wool, the less irritation you'll feel. Look at the label to see the percentage of the blend."

Rx: Always check the tag before you make your purchase. For wool blends, aim for the lowest percentage for the least amount of itch.