April 2007. It began as a joke. Knowing that I love chocolate and have been unhappy to cut back on my intake (last year I gave it up altogether for a few months but have since fallen off the absolutely-no-chocolate wagon), friends began sending me articles reporting that chocolate is a healthful food. So, just for the heck of it, I began doing some research into the matter, and yes, it is true, natural cocoa is extremely rich in antioxidants that have protective cardiovascular effects: http://tinyurl.com/yqvgmc. Some types of cocoa could even increase the flow of blood to the brain, thus improving brain function (http://tinyurl.com/3dvjqg). Cocoa flavanols may prevent diarrhea (http://tinyurl.com/36b2tp), and seem to have a positive effect on our immune system (http://tinyurl.com/2xp2gv). So far, so good. But what about cocoa and MM? In my wildest dreams, I never dreamed that chocolate might be good for cancer patients. Hmmm.
Let’s start with MM. No, I did my best, but (sigh) I did NOT find a specific study on MM and cocoa compounds. However, I did find a 2005 study titled Flavonoids from Theobroma cacao Down-Regulate Inflammatory Mediators, (http://tinyurl.com/2h9bs9) which shows that an unspecified (in the abstract) cocoa extract decreased IL-6 mRNA expression. Remember IL-6? Yes, the inflammatory cytokine that is active in MM and promotes cell proliferation and growth. Among other things, cocoa flavonoids downregulate inflammatory cytokines. Aha! They also downregulate TNF (tumour necrosis factor) alpha. I was not able to read the entire study, but this was enough information to grab my attention. I have already used the study (http://tinyurl.com/22gcme) that examines the effect of EGCG on MM cells. HOWEVER, read this excerpt: the polyphenolic compounds present in green tea include ( â‚¬”)-epigallocatechin-3-gallate, ( â‚¬”)-epicatechin-3-gallate, ( â‚¬”)-epigallocatechin, and epicatechin, which have been shown to have cancer chemopreventive effects in many animal tumor models. [ ] We first examined whether the green tea polyphenols and the polyphenolic epicatechin derivatives induced inhibition of the growth of myeloma cells (IM9, RPMI8226, and U266) [ ]. Now, cocoa contains high levels of epicatechin. True, the tests carried out in this particular study showed that epicatechin was not as strong as EGCG against MM cells, but is it enough to give chocoholic MMers an excuse to eat chocolate now and again?
In the following 2003 study, cocoa was found to be higher in antioxidants than black tea, green tea and red wine: http://tinyurl.com/2sfy2s Could cocoa flavonoids be chemopreventive? It would appear to be so. Norman Hollenberg, a professor of medicine at Harvard University, spent years studying an island-dwelling population off the coast of Panama, the Kuna, who drink a lot of natural cocoa, at least 900 mg a day. It turns out that the Kuna have much lower rates of cancer, stroke, heart failure and diabetes compared to the mainland population: http://tinyurl.com/2o93w6 Note: apparently, flavanols are what give dark chocolate its bitter taste, and frequently get removed in the mass-production process. So if your dark chocolate tastes really bitter, don’t complain, but think of the health benefits, which include fewer calories. Even though the Kuna study is an observational study, not a randomized, controlled clinical trial, it is worth reading. More on chemoprevention: http://tinyurl.com/2ncnzu I also found a 2005 study that examines the cytotoxic effects of pentameric procyanidin (another cocoa compound) on breast cancer cells : http://tinyurl.com/39h4te
And hey!, cocoa beans also contain quercetin (bingo!). But before you start unwrapping a chocolate bar, let me add (sadly) that during the chocolate-making process as much as 90 % of flavonoids are destroyed: cocoa beans are left to ferment in order to get rid of some of the bitterness caused by the flavonoids, and are then roasted. Is there a solution? Sure, look for chocolate bars made with pure cocoa, without any sugars or artificial sweeteners, and forget about milk chocolate. I have tried a 100 % chocolate bar, which is not as pure as what the Kuna drink but will have to suffice, since I don’t have a cacao tree in my back yard.
One last note: the cacao tree was given the scientific name of Theobroma by botanist Carolus Linnaeus. It means “food of the gods.” You may draw your own conclusions