The main nutritional deficiencies that cause dark circles under the eyes are primarily iron deficiency and vitamin B12 deficiency. Iron deficiency leads to anemia, which reduces oxygen supply to the skin and makes the blood vessels under the eyes more visible, causing dark circles. Vitamin B12 deficiency also disrupts red blood cell formation, leading to dull skin tone and worsening under-eye shadows. Other vitamin deficiencies linked to dark circles include vitamins C, K, D, and E, which affect blood circulation, collagen production, and skin integrity, making the skin under the eyes more vulnerable to darkening. Magnesium and zinc deficiencies may also indirectly contribute by causing puffiness and inflammation around the eyes. In summary, iron deficiency is the most common nutritional cause of dark circles, supported by deficiencies in vitamin B12, C, K, D, and E, which all play roles in skin health, blood vessel integrity, and circulation around the eyes.
