Highest Vitamin D Foods — Ranked by Processing Level

Vitamin D deficiency affects an estimated 42% of American adults — making it one of the most widespread nutrient shortfalls. While sunlight is the primary source, dietary vitamin D is important for those with limited sun exposure. The challenge: very few foods are naturally rich in vitamin D, so most dietary vitamin D comes from fortified products.

We analyzed 1.84 million food products with vitamin D data from the USDA FoodData Central database. The data reveals an interesting processing trade-off: the richest natural sources are minimally processed, but fortified products (which dominate the vitamin D landscape) require more processing.

Vitamin D presents a unique case in the processing-nutrition relationship. Natural vitamin D sources are limited: fatty fish (salmon, mackerel, sardines), fish liver oils, egg yolks, and UV-exposed mushrooms. These score Level 1-2 and provide meaningful but modest amounts.

The vast majority of dietary vitamin D comes from fortified products — milk, orange juice, cereals, and plant milks. These achieve higher vitamin D numbers but with more processing. Fortified milk (Level 2) is the most efficient middle ground.

For most people, a combination of moderate sun exposure, naturally vitamin D-rich fish, and modestly fortified dairy provides adequate vitamin D without relying on ultra-processed fortified products.

The RDA for vitamin D is 600 IU (15mcg) per day for adults up to 70, and 800 IU (20mcg) for those over 70. Many experts recommend 1,000-2,000 IU daily, especially for those with limited sun exposure. The upper tolerable limit is 4,000 IU/day. About 42% of US adults are deficient.