Here is what a new study has found.
Chocoholics, rejoice! Eating dark chocolate can reduce stress levels, as well as boost mood, memory and immunity, scientists say.
While it is well known that cacao is a major source of flavonoids, this is the first time the effect has been studied in human subjects to determine how it can support cognitive, endocrine and cardiovascular health.
"For years, we have looked at the influence of dark chocolate on neurological functions from the standpoint of sugar content - the more sugar, the happier we are," said Lee S Berk, from Loma Linda University in the US.
"This is the first time that we have looked at the impact of large amounts of cacao in doses as small as a regular-sized chocolate bar in humans over short or long periods of time, and are encouraged by the findings," said Berk.
Berk served as a principal investigator in two new research studies which show that the higher the concentration of cacao, the more positive the impact on cognition, memory, mood, immunity and other beneficial effects.
The flavonoids found in cacao are extremely potent antioxidants and anti-inflammatory agents, with known mechanisms beneficial for brain and cardiovascular health.
One study examined the impact of 70 per cent cacao chocolate consumption on human immune and dendritic cell gene expression, with focus on pro- and anti-inflammatory cytokines.
Findings showed cacao consumption increases multiple intracellular signalling pathways involved in T-cell activation, cellular immune response and genes involved in neural signalling and sensory perception - the latter potentially associated with the phenomena of brain hyperplasticity.
Another study assessed the electroencephalography (EEG) response to consuming 48 grammes of dark chocolate (70 per cent cacao) after an acute period of time (30 minutes) and after a chronic period of time (120 minutes), on modulating brain frequencies 0-40Hz.
Findings showed that 70 per cent cacao enhances neuroplasticity for behavioral and brain health benefits.
Berk said the studies require further investigation, specifically to determine the significance of these effects for immune cells and the brain in larger study populations.