It’s well-known to most people with a sweet tooth that dark chocolate can be a healthier indulgence.
The sweet treat is packed with fiber and antioxidants, which help prevent cell damage from free radicals. It may also lower the risk of cardiovascular disease, improve blood flow, and lower blood pressure.
Now, a study from Loma Linda University Health in California that was presented last month at the Experimental Biology 2018 annual meeting, sheds more light on the benefits of dark chocolate regarding its effect on brain waves related to memory and recall.
Lee Berk, DrPH, associate dean of research at the School of Allied Health Professions at Loma Linda University, along with his researchers, used 48-gram bars of dark chocolate that were made from 70 percent cocoa beans from Tanzania.
“What we pointed out was that the consumption of antioxidants has the capability to change your brain frequency — a beneficial brain frequency called gamma,” Berk told Healthline. “The gamma frequency is up-regulated, enhanced, turned on by virtue of the chocolate antioxidants.”
Brain waves come in different frequencies, somewhat like a radio.
The gamma frequency is the highest frequency and “associated with the highest level for cognitive processing, for memory, [and] recall,” explained Berk.
As the website Big Think explains, gamma waves address complex functions like information processing, improving memory, and decreasing stress.
The positive effects — or enhanced neuroplasticity, as researchers put it — that eating dark chocolate can have on the brain happens within half an hour.
“[In] this particular study that was presented, we were able to show that after we have subjects consume… a chocolate bar with 70 percent cacao, that after 30 minutes, they had a massive, massive, large increase of gamma frequency in a major area of the brain — that is the back area of the brain and the right side of the brain.”
The increase in gamma frequency brain waves stuck around for several hours.
“We continued to monitor those [test] subjects so that after two hours we were still able to observe — although decreased — a gamma frequency present,” Berk said. “So, it lasts for quite a while.”
This research could be applied to improving cognitive function, especially in aging populations. It suggests that there’s a possibility that one of the benefits of dark chocolate is fine-tuning those cognitive processes as they erode.
“As human beings, as we tend to lose cognitive process — that is, we don’t think as well as we would like to,” Berk explained. “As we age, we lose the ability for optimal cognitive thinking, our processing and memory, and recall.”
He added: “If we indeed can enhance gamma frequency, we might benefit.”
A brief lesson on cacao, cocoa, and chocolate may be helpful to understand the implications of this research.
Cacao seeds, also called cacao beans, are found inside cacao pods. These are football-shaped fruit that grow on trees in hot climates such as Central America, South America, and Africa.
Yes, chocolate technically comes from a fruit. In fact, plenty of other fruits and vegetables are also rich in antioxidants, such as spinach, beets, raspberries, strawberries, goji berries, and of course, kale.
Cacao beans are harvested from inside the fruit, then dried and fermented. This material is eventually turned into cocoa liquor or cocoa butter.
Raw cacao can be consumed on its own or used in baking, usually in small pieces called cacao nibs.
In order to turn raw cacao into a bar of chocolate, cocoa liquor and cocoa butter are combined with sugar and milk.
And in order to turn raw cacao into cocoa, as in the cocoa one might drink as hot chocolate, the product needs to be roasted. Simply put, cacao is the raw, less processed or unprocessed version, while cocoa is processed, explained Berk.
Dark chocolate, milk chocolate, and other types of chocolate taste differently, depending on the varying amounts of liquor, butter, and milk.
Additionally, flavors such as citrus or mint can be added. (A more in-depth explanation of the chocolate making process is explained at Chocolate Alchemy.)
The Food and Drug Administration (FDA) doesn’t have a set limit for what constitutes dark chocolate, so the use of the term in marketing and branding by confectionary companies is somewhat generalized.
But typically, anything above 70 percent cacao will be considered “dark chocolate” and that was the percentage used in Berk’s study.
In human research “with potential for clinical application,” explained Berk, “[it helps that] chocolate is the most desired food in the world — that is, people seem to crave chocolate.”
In other words, people are always going to eat dark chocolate. Therefore, its health benefits and their applications are practical.
“Here you have a food product that not only tastes good — highly desirable — but also has these incredible health-maintaining properties of being antioxidant,” he said.
“Dark chocolate — in the range of 70 percent cocoa or cacao — is extremely, extremely high in antioxidants so it is extremely beneficial,” said Berk.
He noted that it surpasses blueberries, cherries, and other fruits and vegetables with antioxidants.
If you can handle a more bitter taste, then a higher percentage of cacao is even better.
“Eighty-five percent [cacao] is what a lot of healthcare practitioners recommend as your go-to,” explained Jessica Cording, MS, RD, CDN, a registered dietitian in New York.
Simply put, a higher percentage of cacao means less sugar.
“With [85 percent], you’re getting more cacao and less cane sugar. So, you’re able to reap those antioxidant, anti-inflammatory benefits without as many negative consequences of the added sugar in there,” she told Healthline.
Even dark chocolate contains sugar, however, so that should be factored into the equation when consuming it.
“I think chocolate could absolutely be a part of a healthy diet, even if you eat it every day,” continued Cording. “But the dose determines the poison so to speak — or you know, portions matter.”
One to two ounces of dark chocolate daily is typically what experts recommend, Cording said. But the calories from this daily treat should be taken in moderation.
“You want to make sure that the chocolate you’re consuming is fitting within the context of your daily nutritional needs and your daily calorie needs,” she explained. “That way you get to enjoy it, you’ll get the benefits, but you’re not going to have the negative effects of tacking on extra calories to your day.”