Tea, coffee, and dark chocolate (cacao) can improve the health of the brain and eventually help in decreasing the risk of age-related neurodegenerative disorders. Tea, coffee, and dark chocolate (cacao) contain high amount of methylxanthines that are of different types, including caffeine, theophylline, theobromine, and paraxanthine. These compounds act as antagonists of adenosine receptors. These receptors are commonly found in various organs, including skeletal muscles, brain, heart, lungs, and colon. These receptors are involved in motor function, sleep and wakefulness, neuronal signaling, and synaptic plasticity in the central nervous system (CNS). Theophylline and theobromine also act as vasodilators, smooth muscle relaxants, myocardial stimulants, and diuretics. Caffeine also improves memory. Moreover, caffeine also increases the action of painkillers. It can also affect the metabolism and insulin sensitivity, and therefore, commonly used in weight loss supplements.
Camandola, S., Plick, N., & Mattson, M. P. (2019). Impact of coffee and cacao purine metabolites on neuroplasticity and neurodegenerative disease. Neurochemical research, 44(1), 214-227.
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