The media often tells us that dark chocolate is “healthier” than milk chocolate because of its high antioxidant content. Yes, this is true: dark chocolate contains more than four times the amount of antioxidants than milk chocolate (~200 Units/gram vs. ~45 Units/gram; Miller et al. 2006):
However, as shown below, what they neglect to tell us is that cocoa powder beats both dark and milk chocolate, with ~800 antioxidant Units/gram! That translates into 4-fold more antioxidants than dark chocolate, and approximately 18-fold more antioxidants than milk chocolate! So, make your own chocolate at home, with cocoa powder, right?
Maybe not. To make cocoa powder, cacao beans are first roasted at a high temperature. Roasted cocoa beans are processed to remove its cocoa butter, leaving behind the cocoa solids which are then ground, forming cocoa powder. One could argue that the remaining cocoa powder, when used in chocolate is better for health than using raw (non-roasted), ground cacao beans because cocoa powder has less saturated and total fat. Although this is true, roasting the cocoa bean (or any grain, nut, or seed) produces acrylamide, a compound that has been shown to be both neurotoxic and carcinogenic (Burek et al. 1980; Johnson et al. 1986; Friedman et al. 1995). Raw cacao beans, because they have not been roasted, do not contain acrylamide.
How much acrylamide is in a Hershey’s dark chocolate bar? One 43 gram bar contains approximately 30 grams of cocoa powder (70% cocoa solids). Hershey’s cocoa powder contains 909 µg/kg of acrylamide, and when multiplied by 0.03 kg (30 grams), this yields 27.3 µg total acrylamide. The lowest risk for dietary acrylamide-induced toxicity has been recommended to be less than 1.5µg/kg body weight/day (Shipp et al. 2006). This value translates into 75 µg/day for a 50 kg woman, or 112.5 µg/day for a 75 kg man. So, if you eat one Hershey’s dark chocolate bar, you will have ingested a significant amount towards the 75 or 112.5 µg/day upper limit. It’s important to note that there is indeed difference in acrylamide content when comparing Hershey’s and Ghiradelli cocoa powder: Hershey’s contains 3-fold more acrylamide than Ghiradelli (909 µg/kg vs. 316 µg/kg). Therefore, to minimize acrylamide-related risk, if you’re making your own chocolate at home the best thing to do would be to grind your own raw cacao beans, as I do (https://michaellustgarten.wordpress.com/2014/09/21/homemade-chocolate-in-2-minutes/).
Another food that is thought of as “healthy” are baked potato chips, but they’re not healthy in terms of acrylamide content! Baked! Lay’s Original Naturally Baked Potato Crisps have 31 µg of acrylamide per 1 ounce bag. Listed below are other notable sources of dietary acrylamide, including one unhealthy (Pringles), and others commonly thought to be “healthy”.
1 oz. (16 crisps), Pringles Sweet Mesquite BBQ Flavored Potato Crisps: 70 µg of acrylamide
1 oz. (6 crackers), Health Valley Original Oat Bran Graham Crackers: 43 µg of acrylamide
1 serving (2 oz.), Nature’s Path Organic Optimum Power Breakfast, Flax, Soy, Blueberry: 22 µg of acrylamide
1 oz., Blue Diamond Roasted Salted Almonds: 6.7 µg of acrylamide
2 slices, Arnold Bakery Light 100% Whole Wheat Bread: 5.7 µg of acrylamide
If you’re interested, please have a look at my book!
Burek JD, Albee RR, Beyer JE, Bell TJ, Carreon RM, Morden DC, Wade CE, Hermann EA, Gorzinski SJ, 1980. Subchronic toxicity of acrylamide administered to rats in the drinking water followed by up to 144 days of recovery. J. Environ. Pathol. Toxicol. 4,157-182.
Friedman MA, Dulak LH, Stedham MA, 1995. A lifetime oncogenicity study in rats with acrylamide. Fundam. Appl. Toxicol. 27, 95-105.
Johnson KA, Gorzinski SJ, Bodner KM, Campbell RA, Wolf CH, Friedman MA, Mast RW, 1986. Chronic toxicity and oncogenicity study on acrylamide incorporated in the drinking water of Fischer 344 rats. Toxicol. Appl. Pharmacol. 85, 154-168.
Miller KB, Stuart DA, Smith NL, Lee CY, McHale NL, Flanagan JA, Ou B, Hurst WJ, 2006. Antioxidant activity and polyphenol and procyanidin contents of selected commercially available cocoa-containing and chocolate products in the United States. J Agric Food Chem. 31;54(11), 4062-8.
Shipp A, Lawrence G, Gentry R, McDonald T, Bartow H, Bounds J, Macdonald N, Clewell H, Allen B, Van Landingham C, 2006. Acrylamide: review of toxicity data and dose-response analyses for cancer and noncancer effects. Crit. Rev. Toxicol. 36, 481-608.