Cocoa and cocoa products, in addition to other foods high in antioxidants, are known to contain significant contents of antioxidants.

Antioxidants are free radical scavengers. Antioxidants are associated with lower incidence of free-radical induced diseases such as cardiovascular disease, neuro-degenerative disorders (Alzheimer's and Parkinson's diseasses), cancer, and other age-related disorders.

Chocolates are rich in flavonoid antioxidants (especially, epicatechin). A human (in vivo) study reported in the Journal Nature found that intake of dark chocolate increased antioxidant capacity in the blood plasma of the study subjects. According to the same study, milk chocolate and chocolate taken with milk resulted in less antioxidant capacity.

Another research group also reported high antioxidant activity in chocolate and other cocoa products manufactured in the USA. The chocolates evaluated included Hershey's, Ghiradelli, Kroger, Dove and Nestle brands. Below is a list of the cocoa products and their antioxidant activity in ORAC units adapted from the study.

Antioxidant Content in Chocolate and Cocoa

Sample no.Chocolate or cocoa product typeAntioxidant content in ORAC (µmol of TE/g ±SD)
1 Dark chocolate 246.0 ± 32.7
2 Dark chocolate 195.7 ± 3.1
3 Dark chocolate 151.7 ± 33.3
1 semi-sweet chocolate chips 190.3 ± 16.5
2 semi-sweet chocolate chips 177.3 ± 16.8
3 semi-sweet chocolate chips 174.0 ± 23.6
1 Milk chocolate 72.3 ± 5.5
2 Milk chocolate 72.0 ± 2.6
3 Milk chocolate 41.7 ± 1.2
1 Chocolate syrup 66.7 ± 8.7
2 Chocolate syrup 65.7 ± 3.1
3 Chocolate syrup 57.5 ± 6.0

ORAC = oxygen radical absorbance capacity. SD = standard deviation.

Dark chocolate health benefits: reduced risk of blood cloting.
Chocolate flavonoids, health benefits against heart diseases.

Data adapted from: Kenneth B. Miller, David A. Stuart, Nancy L. Smith, Chang Y. Lee, Nancy L. McHale, Judith A. Flanagan, Boxin Ou, and W. Jeffrey Hurst. 2006. Antioxidant Activity and Polyphenol and Procyanidin Contents of Selected Commercially Available Cocoa-Containing and Chocolate Products in the United States. J. Agric. Food Chem., 54 (11), 4062 -4068.

Additional reference: Serafini, M., Bugianesi, R., Maiani, G., Valtuena, S., Santis, D. S., and Crozier, A. 2003. Plasma antioxidants from chocolate. (Dark chocolate may offer its consumers health benefits the milk variety cannot match). Nature, 424:1013.