Strawberries may be the most effective of the five most commonly consumed berries at inducing cancer cell death, according to a recent study conducted at the UCLA Center for Human Nutrition. The center recently tested extracts of six berries -- strawberries, raspberries, black raspberries, blueberries, blackberries and cranberries -- to determine their ability to induce apoptosis, a process that enhances the death of cancer cells.

In one phase of the study, all of the berry extracts exhibited anti-proliferative effects and did so in a dose-dependent manner. The strongest strawberry effects were seen against two types of oral cancer cells and one type of colon cancer cells. A second phase of the experiment measured their ability to induce apoptosis against a cyclooxygenase (COX)-II expressing enzyme colon cancer cell. The results showed that the berries were potent inducers of apoptosis in the human colon cancer cells.

Navindra Seeram, Ph.D., presented the findings of this study at the International Berry Health Benefits Symposium in June.

Strawberries account for 75% of the fresh berry volume sold at retail, followed by blueberries, raspberries, blackberries and cranberries, in descending order. Strawberries and other berries contain high levels of the phytochemicals that are believed to be responsible for the protective effects of diets high in fruits and vegetables against chronic illnesses such as cancer, inflammation, heart disease and neurodegenerative diseases.

The investigators concluded that more in vivo studies are warranted to investigate the impact of berry phytochemicals on human health.