What vitamin deficiency is characterized by diarrhea, dermatitis, and dementia?

The symptoms of diarrhea, dermatitis, and dementia are characteristic of Vitamin B3 (niacin) deficiency, which is also known as pellagra. This condition arises due to inadequate intake of niacin or the amino acid tryptophan, from which niacin can be synthesized in the body.

Pellagra's hallmark symptoms can be summarized as the "three Ds": dermatitis (particularly in areas of sun exposure), diarrhea (often chronic), and dementia (which can lead to severe cognitive decline if untreated). This makes it easily recognizable in clinical practice.

Moreover, niacin is crucial for various metabolic processes, including the production of energy and the synthesis of fatty acids and steroids. Deficiency can occur in populations with limited access to niacin-rich foods, such as those reliant on corn-based diets, where niacin is not bioavailable in sufficient quantities.

The other vitamin deficiencies listed lead to different symptoms and health issues: Vitamin A deficiency primarily affects vision and immune function, Vitamin C deficiency is associated with scurvy and symptoms like fatigue and joint pain, while Vitamin D deficiency primarily affects bone health leading to conditions like rickets or osteomalacia. Therefore, the symptoms observed directly relate to the pathophysiology of niacin deficiency, affirming