You’ve done it. A bad day at work, hard day with the kids, and you find yourself in your chocolate stash scarfing down some — or all — of of a bar. Now science suggests you knew what you were doing. Researchers at Loma Linda University Adventist Health Sciences Center in Southern California presented two small studies at the Experimental Biology 2018 annual meeting held this year in San Diego that found dark chocolate with a high concentration of cacao (beans from which chocolate and cocoa are made) has positive effects on inflammation, mood, memory, immunity, and stress levels. But not just any bar will do. The 10 participants in the two studies were given 40 grams, or 1.5 ounces (oz) of 70 percent cacao dark chocolate and were asked to eat a small piece every two hours they were awake. All the participants had an electroencephalogram (EEG) test to measure gamma waves, a type of brain wave. The results suggest that chocolate could slow oxidative stress, a condition in which the body has too many “free radicals,” the waste products generated by chemical reactions in the body. A study published in March 2014 in the journal Current Neuropharmacology found that oxidative stress may contribute to several mental health disorders, including anxiety. “Cacao has antioxidants that can repair the oxidative stress,” says Lee Berk, PhD, associate dean of research at Loma Linda and the study’s lead author. The researchers say they hope to publish their findings soon. Dr. Berk says his team’s next step is to research exactly how much dark chocolate someone should eat to affect brain function. (He says that he eats some every day.) The amount the study participants ate is about 1.5 oz and has about 165 calories. That’s fewer calories than most chocolate bars you’d find at the candy counter, which generally have more sugar and far less cacao. Bradley Biskup, a researcher and physician assistant in the lifestyle modification unit of the Pat and Jim Calhoun Cardiology Center at the University of Connecticut in Farmington, says that there has been speculation about the effects of chocolate, but the Berk study is one of the few to prove what we’ve strongly suspected. “Research costs money and it can be hard to get funding for nutrition studies, which is why this hasn’t been done before,” Biskup says. How much to eat for maximal benefit remains an open question. A very large Danish study published in March 2017 in the journal BMJ Heart, involving 55,502 participants (26,400 men and 29,102 women) ages 50 to 64, found that people who ate a 1-oz serving of chocolate (not necessarily dark) two to six times each week had a 20 percent lower rate of atrial fibrillation (an irregular heartbeat that can lead to blood clots, stroke, heart failure, and other heart-related complications) compared with people who ate the same size serving less than once a month. In the Berk study, participants ate several small portions during the day, “to keep their antioxidant levels constant,” says Berk. The goal, Biskup says, is to get the benefit of the cacao’s antioxidants without risking weight gain from too many chocolate calories. Biskup, who specializes in lifestyle modification, says he teaches his patients meditative breathing to relieve stress and then suggests an ounce of dark chocolate as a treat that can enhance the stress relieving effects of the breathing. Your taste buds may have to adapt to the slightly less-sweet taste of dark chocolate if you more commonly eat milk chocolate, Biskup says, adding: “It takes about 20 to 25 days to get fully used to it.”
