Spinach is a dark green leafy vegetable that is a good source of nutrients. Boiling spinach can reduce the levels of vitamin C, niacin, folate and lutein, but it doesn't get rid of them completely. One cup of raw spinach leaves has much less spinach than a same-sized cup of boiled spinach; therefore, it is better to make comparisons according to weight rather than by volume.
One hundred grams of raw spinach contains 28.1 milligrams of vitamin C, while 100-grams boiled spinach has 9.8 milligrams. Vitamin C is needed for immune system function, healthy blood vessels and connective tissue, and is needed for normal wound healing. The Institute of Medicine sets the dietary reference amount of vitamin C at 75 milligrams per day for women and 90 milligrams per day for men.
One hundred grams raw spinach has 0.724 milligrams of niacin. One hundred grams boiled spinach has 0.490 milligrams of niacin, also known as vitamin B-3, is needed for many biochemical reactions to occur and it's required to convert food to energy. The Institute of Medicine sets the dietary reference amount of niacin at 16 milligrams per day for men and 14 milligrams per day for women.
One hundred grams raw spinach has 194 micrograms of folate. One hundred grams boiled spinach has 146 micrograms. Folate is a B vitamin needed for red blood cell production and to metabolize amino acids. The Institute of Medicine sets the dietary reference amount of folate at 400 micrograms per day for all adults.
One hundred grams raw spinach contains 12,198 micrograms of lutein and zeaxanthin, while 100-gram boiled spinach has 11,308 micrograms of lutein and zeaxanthin. Lutein is a phytochemical related to vitamin A and beta carotene. It works as an antioxidant that protects your cells from free radical damage. While boiling spinach actually increases the amounts of vitamin A and beta carotene that are available, it reduces the amount of lutein.