Peas benefit your immune system with antioxidant vitamins, especially if you eat them raw. A cup of raw peas has 58 milligrams of vitamin C, providing 65 percent of the daily requirement for men and 77 percent for women. The same amount of cooked peas has 23 milligrams of vitamin C. Peas are also rich in Bvitamins. A cup of cooked or raw peas provides about onethird of the thiamine you need each day and 20 to 25 percent of your recommended daily intake for riboflavin, niacin, vitamin B6 and folate. It also contains nearly half your RDI for vitamin K.