Dark Chocolate and Your Health
Valentine’s Day has just passed and many people got some chocolates as a gift. There are a lot of misconceptions out there about chocolate and whether it is good for you or not. What type of chocolate is better? Etc…
Let’s take a serious and in depth look at the scientific evidence on Chocolate and your health. What follows is a simplified version of an evidence review that I conducted for an oral exam for my PhD. It is in four parts. I will release one part each day (today and the next 3 days). I hope you find this entry informative and it helps you stay on track and avoid being sucked into the marketing “traps” that are out there. Please comment with any questions or thoughts you might have!
The first potential benefit that we’ll cover today is the anti-inflammatory effect of dark chocolate.
1) Anti-Inflammatory Effects – Compounds known as polyphenols [1, 2] and flavonols [1, 3] found in dark cocoa solids are known to decrease inflammations by the following mechanisms. We need at least 85% of cocoa solids to see significant benefits here.
a. Free radical scavenging – flavonols show greater free radical scavenging compared with Vitamin C and Beta Carotene [3, 4].
Flavonols have been shown to effectively impair reactive oxygen species production (free radical type) as well as neutralize existing free radicals [3, 5-7].
Compounds in dark chocolate solids (epicatechin, catechin and procyanidin B2) are known to reduce oxidative destruction of red blood cells in a dose-dependent manner [3, 8, 9].
b. Altering Gene Expression – Simply put, if gene expression is altered, then protein production is subsequently altered, since genes code for proteins that carry out specific functions in our bodies. Flavanol compounds have been shown to alter gene expression (mRNA and DNA) and therefore affect the amounts and types of proteins produced, thereby effecting key function of the body [1, 3].
Cocoa flavanols decrease production of pro-inflammatory interleukins (IL-1β, IL-2 [1, 10-15] and TNF-α [1, 16-18]) by altering expression and production of mRNA, which is responsible for protein transcription and translation. Cocoa flavanols have also been shown to increase production of anti-inflammation compounds TGF-β + IL-4 [1, 16-18].
IL-5 predicts risk for specific oral infections and in turn predicts incidence of CAD [1, 19, 20] and larger cocoa flavanols decrease production of this compound [1, 21] therefore, decreasing risk of CAD.
So that’s the evidence of the anti-inflammatory benefits of dark chocolate summarized for you. Clearly, there are some benefits of consuming dark chocolate. However, it’s important that you realize that these benefits were only observed in dark chocolate containing at least 85% cocoa solids, which provided enough of the cocoa flavanols to be effective on lowering/preventing inflammation via the mechanisms above.
I hope this helps.
Stay tuned tomorrow when I will release the next potential health benefit of dark chocolate – Immune Cell Function.
Have a great day!
Live healthy, live passionate, live prosperous, live long!
1. Selmi, C., et al., Chocolate at heart: the anti-inflammatory impact of cocoa flavanols. Mol Nutr Food Res, 2008. 52(11): p. 1340-8.
2. Schroeter, H., et al., (-)-Epicatechin mediates beneficial effects of flavanol-rich cocoa on vascular function in humans. Proc Natl Acad Sci U S A, 2006. 103(4): p. 1024-9.
3. Ramiro-Puig, E. and M. Castell, Cocoa: antioxidant and immunomodulator. Br J Nutr, 2009. 101(7): p. 931-40.
4. Nakao, M., S. Takio, and K. Ono, Alkyl peroxyl radical-scavenging activity of catechins. Phytochemistry, 1998. 49(8): p. 2379-82.
5. Hatano, T., et al., Proanthocyanidin glycosides and related polyphenols from cacao liquor and their antioxidant effects. Phytochemistry, 2002. 59(7): p. 749-58.
6. Yilmaz, Y. and R.T. Toledo, Major flavonoids in grape seeds and skins: antioxidant capacity of catechin, epicatechin, and gallic acid. J Agric Food Chem, 2004. 52(2): p. 255-60.
7. Pollard, S.E., et al., The reaction of flavonoid metabolites with peroxynitrite. Biochem Biophys Res Commun, 2006. 350(4): p. 960-8.
8. Zhu, Q.Y., et al., Inhibitory effects of cocoa flavanols and procyanidin oligomers on free radical-induced erythrocyte hemolysis. Exp Biol Med (Maywood), 2002. 227(5): p. 321-9.
9. Zhu, Q.Y., et al., Influence of cocoa flavanols and procyanidins on free radical-induced human erythrocyte hemolysis. Clin Dev Immunol, 2005. 12(1): p. 27-34.
10. Mackenzie, G.G., et al., Epicatechin, catechin, and dimeric procyanidins inhibit PMA-induced NF-kappaB activation at multiple steps in Jurkat T cells. FASEB J, 2004. 18(1): p. 167-9.
11. Mackenzie, G.G. and P.I. Oteiza, Modulation of transcription factor NF-kappaB in Hodgkin’s lymphoma cell lines: effect of (-)-epicatechin. Free Radic Res, 2006. 40(10): p. 1086-94.
12. Mao, T., et al., Cocoa procyanidins and human cytokine transcription and secretion. J Nutr, 2000. 130(8S Suppl): p. 2093S-9S.
13. Mao, T.K., et al., The effect of cocoa procyanidins on the transcription and secretion of interleukin 1 beta in peripheral blood mononuclear cells. Life Sci, 2000. 66(15): p. 1377-86.
14. Sanbongi, C., N. Suzuki, and T. Sakane, Polyphenols in chocolate, which have antioxidant activity, modulate immune functions in humans in vitro. Cell Immunol, 1997. 177(2): p. 129-36.
16. Mao, T.K., et al., Modulation of TNF-alpha secretion in peripheral blood mononuclear cells by cocoa flavanols and procyanidins. Dev Immunol, 2002. 9(3): p. 135-41.
17. Ramiro, E., et al., Flavonoids from Theobroma cacao down-regulate inflammatory mediators. J Agric Food Chem, 2005. 53(22): p. 8506-11.
18. Ramiro-Puig, E., et al., Spleen lymphocyte function modulated by a cocoa-enriched diet. Clin Exp Immunol, 2007. 149(3): p. 535-42.
19. Beck, J.D., G. Slade, and S. Offenbacher, Oral disease, cardiovascular disease and systemic inflammation. Periodontol 2000, 2000. 23: p. 110-20.
20. Joshipura, K., C. Ritchie, and C. Douglass, Strength of evidence linking oral conditions and systemic disease. Compend Contin Educ Dent Suppl, 2000(30): p. 12-23; quiz 65.
21. Okudaira, H. and A. Mori, Simple understanding and optimistic strategy for coping with atopic diseases. IL-5 central hypothesis on eosinophilic inflammation. Int Arch Allergy Immunol, 1998. 117(1): p. 11-9.