Purina One +Plus Helps Minimize Hairballs, Experience the combined power of nature and research in Purina ONE +PLUS Hairball Formula adult dry cat food. Along with a great taste cats love, this easily digestible recipe includes a SmartBlend of high-quality ingredients that get to work in your cat. Driven by nature, the hairball control cat food starts with real chicken as the #1 ingredient and has 38 grams of protein per cup, helping to support her strong muscles, including her healthy heart.