Table 3

Some advantages and disadvantages of berry powders, extracts, and individual anthocyanins for cancer chemoprevention

PowdersContain multiple chemopreventive agentsDifficult to standardize
Modulate multiple events in carcinogenesisStability of berry components influenced by several factors
Seem to cause little or no toxicity Potential contamination with microbes and chemicals
Can be administered in different formulationsApparent need for high consumption to be effective
Relatively inexpensive Seasonal availability of some berry types
ExtractsPotentially contain several chemopreventive agentsMore difficult to prepare than powders
Modulate multiple carcinogenic events in vitroSome components unstable
More easily standardized than powdersEfficacy in vitro is variable-high doses usually required
Seem to cause little toxicity High doses required for in vivo efficacy when given orally
Can be administered in different formulationsMay be expensive
Useful for topical application to precancerous lesions
AnthocyaninsEasily standardized Unstable at alkaline pH
Can be modified to improve bioavailabilityDifficult to synthesize
Influence multiple events in carcinogenesisHigh doses required for in vitro efficacy
Can be administered in different formulations Poor bioavailability
Cause little toxicity Expensive