Fruits are a wonderful and delicious part of a healthy diet. In fact the 2005 Dietary Guidelines for Americans recommends that we all consume at least 2 cups of fruit per day based on a 2,000-calorie diet. With the variety of fruits available, this should be an easy target for all of us. In addition to being rich in nutrients like dietary fiber, fruits are rich in a variety of antioxidant phytochemicals that might confer a variety of human health benefits, including cancer fighting benefits.
A breast cancer study published last year in the Journal of Agriculture and Food Chemistry explored the ability of antioxidant phytochemicals from peaches and plums to reduce breast cancer cell growth in culture. For this study, researchers developed extracts from the Rich Lady peach variety and the Black Splendor plum variety and used them to treat different breast cancer cell lines and healthy, non-cancerous breast cells. The researchers reported
The peach extract at a concentration of 42 mg/L inhibited proliferation of estrogen-independent breast cancer cells by 50%.
A 50% inhibition of cell growth in estrogen-dependent breast cancer cells and non-cancerous breast cells required substantially higher doses.
The plum extract showed similar, though weaker, results, being more effective against the estrogen-independent breast cancer cells compared to the other breast cancer cells tested.
Analysis of the antioxidants found in these plum and peach extracts showed that the flavonoids and procyanidins were the most effective, while the phenolic acids and anthocyanins were less effective.
While the phenolic acids were some of the lesser effective compounds, they still showed a relatively potent cancer fighting effect on estrogen-independent breast cancer cells while having very low toxicity in normal breast cells.
These are interesting results that show the potential cancer fighting benefits of peaches and plums. However it is clear that more research needs to be done. This current study was done in a cell culture system, though a recent press release about this study suggests that feeding these extracts to animals prevented cancer growth. While these early results are promising and give us another good reason to include fruits in our daily diet, additional animal studies and human clinical trials will need to be done to understand the full benefits of peaches and plums for breast cancer. According to the USDA Database for the Flavonoid Content of Selected Foods, raw peaches and plums have much lower natural levels of these compounds than what was used in the extracts studied. So while consuming fruits like peaches and plums is a good idea for a number of reasons, extracts or compounds derived from extracts might be needed to see their cancer fighting benefits.