The article discusses four key skincare ingredients that dermatologists and research have confirmed to be effective: sunscreen, retinoids, niacinamide, and hydroxy acids. Sunscreen is highlighted as essential for shielding the skin from harmful UV rays and reducing the risk of skin cancer, with studies showing its effectiveness in preventing squamous cell carcinoma and melanoma. Retinoids, which are derivatives of vitamin A, are noted for their ability to enhance cell turnover and address sig