Burk also conducted a small study on how chocolate boosts the immune system. Ten subjects were given dark chocolate and Burk noted that they found an increase of anti-inflammatory markers, T cells and infection-fighting cells.
Both of Burk's studies were only conducted on 10 participants, and the findings were announced at a scientific meeting, but not published in a medical journal. They were not peer-reviewed before the release, ABC News reported. Burk presented his findings at the Experimental Biology 2018 annual meeting, USA Today reported.
Berk told USA Today that the study was funded by Loma Linda University's School of Allied Health Professions, and was not affiliated with chocolate companies.
A third study that was published in a medical journal -- JAMA Ophthalmology -- showed that dark chocolate can boost vision. Researchers gave 30 participants dark and milk chocolate bars then did a vision test two hours after the the bars were eaten. They had small vision improvements after eating the dark chocolate, ABC News reported.
Mostly they saw an improvement in contrast sensitivity. They were able to separate objects in low light or high glare situations.
Doctors believe that the chocolate affects blood vessel function and blood pressure, or basically allowing more blood to flow into the eye, according to ABC News.
But before you dig into the Hershey bars, the doctors said the key is dark chocolate that has 70-percent cacao, or those bitter, super-dark, dark chocolate bars, USA Today reported. Normally a chocolate bar has 11 percent cacao. ABC News reported.