Vitamin D3 is important for bone health, brain health, and anti-cancer properties. Here are 5 foods rich in Vitamin D3: 1. Rainbow trout: 3 ounces of rainbow trout provides 645 IU of Vitamin D3, which is 81% of the daily value (DV). 2. Sockeye salmon: Sockeye salmon contains 570 IU of Vitamin D3, which is 71% of the DV. 3. Sardines: A can of sardines provides around 200 IU of Vitamin D3. 4. Egg: One egg contains 44 IU of Vitamin D3, which is 6% of the DV. 5. Beef liver: 3 ounces of beef liver contains 42 IU of Vitamin D3, which is 5% of the DV. These foods are not only rich in Vitamin D3 but also contain other important nutrients.