Mushrooms are as rich in antioxidants as more colourful vegetables according to a Penn State University study.

US researchers ranked portabella and crimini mushrooms up with carrots, green beans, red peppers and broccoli as sources of dietary antioxidants.

Using the ORAC test (Oxygen Radical Absorbance Capacity), which measures how powerfully and quickly foods inhibit oxidative agents, showed portabella mushrooms had an ORAC value of 9.7 and criminis 9.5. Carrots and green beans have an ORAC value of 5, red pepper 10, and broccoli 12.

Anti-oxidants inhibit increased rates of oxidation, which can damage proteins, lipids carbohydrates and DNA, sometimes causing cancer.