Yet cinnamon itself isn't the problem.
New research from scientists at the University of MI (or U of M) revealed that cinnamaldehyde, an essential oil that gives the spice its flavor, appears to have an anti-obesity effect, Newsweek reported. Therefore, instead of storing fat, the cinnamon substance induced adipocytes to start burning energy in a process called thermogenesis.
The fat-burning effects were observed in human cells by University of MI scientists, who also elucidated the underlying thermogenic mechanisms.
University of Michigan Life Sciences Institute researchers, led by Research Assistant Professor Jun Wu, aimed to use this research as a foundation to better understand cinnamaldehyde and whether these positive effects could be translated to humans. Overall metabolic health is improved as a result, and fat is burned.
"Inhibition of PKA or p38 MAPK enzymatic activity markedly inhibited the CA-induced thermogenic response", wrote the article's authors. Human adipose stem cells were differentiated and treated with CA to assess whether the CA-mediated signaling is conserved in humans. In addition, chronic CA treatment regulates metabolic reprogramming, which was partially diminished in FGF21KO adipocytes.
To observe cinnamaldehyde's actions, the researchers gathered fat cells from volunteers ranging in body mass indices, ethnicities, and ages. This long-term storage was advantageous for our distant ancestors who had much less access to fats and thus had a much greater need to store fat. This is because stored fat can be used when food is scarce or the temperature's cold, where fat cells can convert energy stored into heat.
"It is only recently that the excess of energy had become a problem". "Throughout evolution, the opposite-energy deficiency-has been the problem".
With the rising obesity epidemic, researchers have been looking for ways to prompt fat cells to activate thermogenesis, turning those fat-burning processes back on.
Cinnamon might be the latest food ingredient to be enlisted to fight obesity.
Wu believes that cinnamaldehyde may offer one such activation method.
"Cinnamon has been part of our diets for thousands of years, and people generally enjoy it", Wu said. "So, if it helps to protect from obesity, it can offer a way of improving metabolic health".
Since the studies so far have focused on mice and human cells, Wu suggests further investigation is needed to understand how to achieve the metabolic benefits of cinnamaldehyde without any adverse side effects.