Toxicology 166 (2001) 63 – 69 Comparison of the antioxidant content of fruits, vegetables and teas measured as vitamin C equivalents Rene ´ du Toit, Yolanda Volsteedt, Zeno Apostolides * Department of Biochemistry, Uniersity of Pretoria, Pretoria 0002, South Africa Received 25 May 2001; accepted 29 May 2001 Abstract Most of the health benefits of black, green and oolong teas made from Camellia sinensis are attributed to their antioxidant content. Many plants and spices have been used to make infusions that are erroneously referred to as ‘teas’. The term ‘rich in antioxidants’ is often used to describe such infusions, often without scientific support. We have used the DPPH method to quantify the total radical scavenging capacity (RSC) of a wide range of ‘teas’, fruits and vegetables. The results are presented as vitamin C equivalents. These results are compared to the RSC of the recommended portions of fruits and vegetables in the food guide pyramid for a healthy and balanced diet. The EC 50 results show that there are no statistically significant differences in the RSC of black, green and oolong teas. However, the RSC of ‘teas’ made from other species of plants are significantly lower. Our results show that one or two cups of tea would provide a similar amount of RSC as five potions of fruits and vegetables or 400 mg vitamin C equivalents. This would be comparable to two capsules (200 mg) of vitamin C. Caution is advised in extrapolating these in vitro results to humans due to bioavailability. © 2001 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Food-guide pyramid; Fruits and vegetables; Tea; Antioxidants; Radical-scavenging capacity; 2,2-diphenyl-1-picrylhy- drazyl; Epigallocatechin gallate www.elsevier.com/locate/toxicol 1. Introduction Increased consumption of fruits and vegetables has been associated with protection against vari- ous diseases, including cancers (Goodwin and Brodwick, 1995; Steinmetz and Potter, 1996) and cardio-and cerebrovascular diseases (Rimm et al., 1996). This association is often attributed to the antioxidants in the fruits and vegetables such as vitamin C, vitamin E, carotenoids, lycopenes and flavonoids that prevent free radical damage (Steinberg, 1991; Sta ¨helin et al., 1991; Willett, 1994). Tea, the most popular beverage after water throughout the world, has attracted much interest because of reported health benefits since antiq- uity. These benefits have recently been associated * Corresponding author. Tel.: +27-12-420-2486; Fax: + 27-12-362-5302. E-mail address: zeno.apostolides@bioagric.up.ac.za (Z. Apostolides). 0300-483X/01/$ - see front matter © 2001 Elsevier Science Ireland Ltd. All rights reserved. PII:S0300-483X(01)00446-2