Dealing with dry scalp is no laughing matter. It means that your scalp severely lacks the natural oils to keep it healthy and moisturized. Dandruff, when not treated right away, can lead to a variety of skin conditions like eczema and scalp psoriasis. But what exactly is dandruff? Dandruff is caused by a type of yeast on your scalp called Malassezia, and while it kind of sounds gross, it's …