Steamed Vegetables Provide the Most Nutrients, Microwaved or Boiled Does Nothing for the Body

Steamed vegetables, compared to boiled vegetables provide the body with the most nutrients, according to a new study.

The study finds that boiling or microwaving broccoli leaves the body with no cancer-fighting properties. Broccoli is a type of vegetable that is a source of sulforaphane which is protective against cancer and is formed due to the enzyme myrosinase which is found in the said vegetable. Researchers found that the best way to preserve myrosinase is to steam broccoli for four minutes.

Scientists involved in the study who presented their results at the American Institute for Cancer Research Annual Research Conference found that the best way to cook vegetables is to steam it for three to four minutes instead of cooking or boiling or even using the microwave for heating. They confirmed that steaming vegetables turns it into a bright green color that can then help enhance cancer-fighting compounds.

However, the researchers found that steaming vegetable for five minutes is the best way to retain enzymes found in vegetables, specifically in broccoli. "Past food processing has tended to focus on improving the taste, visual and microbiological safety," said Dr. Elizabeth Jeffery, a researcher at the University of Illinois at Urbana-Champaign.

"Now our task is to go further. Processing can ensure that the bioactives - the cancer protective compounds - arrive in your digestive system in a form the body can use," he added. Dr. Jeffery discovered that boiled or microwaved broccoli can still produce sulforaphane if it is consumed with other raw foods that contain myrosinase enzymes.

"As we're learning, food processing isn't just what happens to food before it reach the grocery shelves," said American Institute of Cancer Research Associate Director of Nutrition Programmes Alice Bender.  "This research highlights that what you do in your kitchen can make those fruits and vegetables on your plate even more cancer protective."