If Sherlock Holmes were on the case of your itchy, inflamed, and flaking skin, he might suggest looking inside for clues. Sometimes, our bodies are trying to tell us something. They send us dry, irritated, and scabby skin to get our attention. People living with psoriasis feel like their bodies are always sending them an SOS, but they often struggle to know what to do about it. Vitamin D deficiency can cause painful skin irritation. If you already have psoriasis, it can make it worse. Adding Vitamin D to your diet can help eliminate one possible cause of your outbreaks.