Combination skin has both oily and dry areas. The T-zone, which is straight down the middle of the face, will have larger pores and secrete more oil, while the outer part of the face will be normal or dry. It can also appear dry or flaky due to by dehydration. The goal with this skin type is to use products that can address both oily and dry areas, using water-based products that cleanse and exfoliate to help keep the skin balanced.
Dehydrated skin is a lack of water in the skin. This can happen due to over-exfoliation, harsh product use, medications, and the environment. The goal with this skin type is to use products that help keep the skin hydrated. Using products with humectants will draw water back into the skin while occlusive products will help prevent transepidermal water loss (TEWL).