Foods high in Vitamin D (D2 + D3)

Why Vitamin D (D2 + D3) matters

Vitamin D is a fat-soluble secosteroid that acts as a prohormone — your skin synthesizes it from cholesterol when exposed to UVB sunlight. It regulates calcium and phosphorus absorption in the gut, which makes it essential for bone mineralization, muscle function, and immune regulation. Food sources are comparatively scarce: fatty fish (salmon, sardines, mackerel), cod liver oil, UV-exposed mushrooms, and egg yolks are the main natural sources, while most Americans get the bulk of their intake from fortified milk, plant milks, cereals, and orange juice. Adults need 15 to 20 µg (600 to 800 IU) per day, and people with limited sun exposure, darker skin, or living above 40 degrees latitude often need supplementation.

Daily intake reference

Signs of low intake

Vitamin D insufficiency is common — the NIH estimates roughly 25 percent of US adults have low blood levels. Symptoms include bone pain, muscle weakness, frequent infections, low mood, hair loss, and slow wound healing. Severe long-term deficiency causes rickets in children and osteomalacia (soft bones) in adults. A 25-hydroxyvitamin D blood test is the standard diagnostic — most labs flag levels below 20 ng/mL as deficient. People with inflammatory bowel disease, those on long-term steroid therapy, and individuals with obesity are at higher risk.

Best for these diets

Vitamin D-rich foods fit naturally into these dietary patterns:

• Mediterranean
• high protein
• Keto
• Paleo