Several foods are good sources of vitamin B9 (folate). Leafy green vegetables like spinach, kale, and broccoli are rich in folate. Legumes such as lentils, chickpeas, and black beans also contain significant amounts of this vitamin. Citrus fruits like oranges and grapefruits, as well as avocados, provide folate as well. Other folate-rich foods include asparagus, Brussels sprouts, beets, fortified cereals, and some nuts and seeds. It's important to note that cooking and food processing methods can affect the folate content in foods, so it's advisable to consume a varied diet with a mix of fresh, unprocessed foods to ensure sufficient intake of vitamin B9.