It was a significant moment in human pre-history when someone realised that if you tilt your pelvis forward a little you can wander around on two feet leaving your hands free. It was another pivotal point when it was realised that you can do more with opposable thumbs than play rock marbles. Do these, and any other moments, though compare to that instant, around 8000 years ago, when humanity domesticated the grape?
Grapes naturally carry yeast on their skin which made them prime potentials for the discovery of an alcoholic beverage, but wine is by no means the end of the grape-and-humanity story. Grapes are a delicious and healthy food when eaten raw, plus we can make them into jam, juice, jelly and vinegar, dry them into sultanas and extract their oil. These days we are also discovering that even the seeds of grapes have something to offer.
Both red and, to a lesser extent, white grapes provide antioxidants. It is the seeds of white grapes, however, that pack a real antioxidant punch. The coating of white grape seeds yields substances known as “oligomeric proanthocyanidin complexes†(OPCs) which have an antioxidant effect around 50 times greater than vitamin C or vitamin E. These OPCs have been well studied over the last couple of decades but now a new study has found that they can be effective in preventing colorectal cancer.
In the new study, colorectal cancer cells of varying stages were exposed to grape seed extract. When using chemotherapy larger doses are required to kill stage IV cancer cells than are needed for stage II. However, the reverse is true for grape seed extract. It took less than half of the extract to kill stage IV cells compared to stage II cells.
So grape seed extract preferentially has a negative effect on more advanced stage colorectal cancer.
It seems that the mutations that allow colorectal cancer cells to survive and spread (metastasise) through the body make them vulnerable to grape seed extract. A colorectal cancer cell can have up to 11,000 genetic differences to a “normal†cell and chemotherapy may only target a specific mutation. As cancer progresses more changes occur, which can make the cancer resistant to chemotherapy. The encouraging thing, according to these researchers, is that since grape seed extract contains many bioactive compounds, beyond OPCs, it may be able to target multiple mutations. They believe that grape seed extract increases oxidative stress in cancer cells causing the cells to die.
Of course, this is not a license to self-treat for cancer, but it is a very encouraging sign and also a pointer to a safe but useful preventative measure for anyone at risk.
