Which is better for you: raw or cooked vegetables? The answer may surprise you, says Tammy Roberts, a University of Missouri Extension nutrition and health education specialist.
"We've always heard that raw vegetables are healthier than cooked because cooking destroys nutrients," said Roberts. "In some cases that's not true."
For example, cooking tomatoes actually increases the amount of lycopene, the chemical that gives the tomato its red color. Studies have linked intake of lycopene, an antioxidant, with lower risk of cancer and heart attacks.
"Antioxidants help prevent or repair damage to body cells, which is important for decreasing risk of cancer," Roberts said. "They are also thought to improve immune function."
Cooked carrots are richer in beta carotene, an antioxidant that the body converts to vitamin A (also an antioxidant) and that helps promote normal vision, protect from infection and regulate the immune system, Roberts said.
There may also be additional antioxidant activity in cooked spinach, mushrooms, asparagus, cabbage and peppers.
The best cooking method for preserving antioxidants is boiling or steaming, Roberts said. Frying is not recommended because the antioxidants break down in the frying process.
In other instances, raw vegetables are better. For example, polyphenols (which are also antioxidants) are lost when you cook carrots. In broccoli, heat damages the enzyme myrosinase, which helps prevent cancer.
Vitamin C, a powerful antioxidant found in many vegetables, can be destroyed by heat.
So should we be eating our vegetables raw or cooked?
"Most likely you already have been eating your vegetables sometimes raw and sometimes cooked, which is what is recommended," Roberts said. "This way you get the best of both worlds. When they are cooked you are getting higher levels of some nutrients and when they are raw you get higher levels of other nutrients."
For more information from MU Extension on food and nutrition, see http://missourifamilies.org/nutrition/.