Theobromine is the main component in the chocolate. Theobromine differs from caffeine present in the coffee at structural level with the absence of an additional methyl group which is present in caffeine but not in theobromine. If the caffeine in the coffee is metabolized to shed off its methyl group, it would be converted to theobromine giving the flavour and taste of a chocolate. Methyl group is an organic moiety with one carbon atom in the centre joined covalently with three hydrogen atoms. It is an important molecule in maintaining the functional and structural properties of molecules present in biochemical and chemically important pathways. For instance, to cross the blood-brain barrier, a methyl group is required. This is the reason coffee has soothing effects energizing our nervous system while chocolate only provides taste, flavour and relaxes our muscles (Ranjitha & Sudha, 2015).
Mechanism of action of caffeine and theobromine
The primary difference between caffeine and theobromine is depicted more precisely at molecular levels. Both molecules belong to the same family of organic compounds commonly called as Methyl-Xanthine family. The molecules belonging to this family are usually involved in the nervous system stimulation. At the molecular level, these molecules bind to the Adenosine receptors present in the neuronal network whereby blocking these receptors to bind to their natural ligand. These receptors are involved in the reduction of neuronal activities. Thus, these molecules enhance the neuronal activity.
This binding of caffeine and theobromine to adenosine receptors helps in the alertness and active response of an individual associated with increased consumption of coffee (Kuribara, Asahi, & Tadokoro, 1992). The studies have shown that caffeine is way stronger in its affinity with adenosine receptors than theobromine. Caffeine competes with adenosine, which is the ligand for adenosine receptors much strongly and has two to three times more affinity for adenosine receptors than theobromine. Thus, the role of theobromine in controlling central neuronal network is not evident as studies suggest. It might have an effect on cardiac muscles as a stimulant, but the consumption of theobromine is not an addictive one, unlike caffeine. Although theobromine has been identified as among the molecules present in the chocolate which stimulates sexual response (Daly, Butts-Lamb, & Padgett, 1983).
Theobromine has two methyl groups while caffeine has three methyl groups. This helps in the recognition and binding of caffeine to adenosine receptors and cross the blood-brain barrier. Once, caffeine crosses the blood-brain barrier it affects the neuronal network to stimulate their functioning. This results in a more energized response of neurons to all the stimulus. This is how coffee creates alertness after consumption (Reading).
Coffea Arabica, or coffee beans, and seeds are the main source of caffeine. Caffeine stimulates the central nervous system. Caffeine is also affected by the cardiac and skeletal muscles and also caused the relaxation of smooth muscles. It also stimulates respiratory system. On the other hand, the primary source of chocolate or theobromine is Theobroma cacao or cocoa plant seeds. Theobromine action is much like caffeine and is diuretic. Its effect is on smooth muscles relaxation and is a cardiac stimulant. The action of caffeine and theobromine is almost similar (Martínez-Pinilla, Oñatibia-Astibia, & Franco, 2015). The only difference is that caffeine has a substantial effect on nervous system stimulus, while theobromine affects smooth muscles significantly.
In a behavioural investigation, caffeine consumption enhanced alertness and state of mind over a time of 24 hours. Theobromine produces gentle, beneficial outcomes in joy, yet does not influence on attention and alertness in moderate consumption as compared to caffeine (Ruxton, 2008).
In other words, theobromine has gentle, mild, slow onset and long-lasting effect. While caffeine has intense, robust and fast acting and rapid dissipation effect, Theobromine is 50% in the bloodstream after 6 to 10 hours and caffeine is 50% in the bloodstream after 2 to 5 hours. Theobromine is considered as mild anti-depressant while caffeine increases emotional stress (Brehm, 2015).
Side effects of caffeine and theobromine use
There is also some health issues with the more consumption of caffeine as compared to theobromine. More intake of caffeine cause heart problems, stress and dehydration headaches. Some peoples also allergic by using caffeine. People also become mild addictive to it when using caffeine. It is extremely diuretic so requires a large intake of fluids to balance the diuretic effect. Further investigation shows that caffeine use decreased sperm count (in rats), and cite caffeine as a factor in 2 percent of miscarriages (Bhambra, Pena-Fernandez, & Evans, 2017).
Theobromine act as anticancer. It is used in current medicine as a vasodilator, a urination aid and as a heart stimulant. It is considered as one of the main components of a chocolate name as an aphrodisiac. But it also causes sleeplessness, anxiety and loss of appetite. The reason behind this is that some animals metabolize theobromine very slowly (such as dogs, cats, birds and horses), so that it can be toxic and even fatal when ingested. However, theobromine poisoning is treatable if caught early (Bhambra et al., 2017).
Bhambra, A. S., Pena-Fernandez, A., & Evans, M. (2017). Health Effects and Risks of Caffeine, Theobromine and Theophylline: Bentham Science.
Brehm, B. A. (2015). Nutrition: Science, Issues, and Applications [2 volumes]: Science, Issues, and Applications: ABC-CLIO.
Daly, J. W., Butts-Lamb, P., & Padgett, W. (1983). Subclasses of adenosine receptors in the central nervous system: interaction with caffeine and related methylxanthines. Cellular and molecular neurobiology, 3(1), 69-80.
Kuribara, H., Asahi, T., & Tadokoro, S. (1992). Behavioral evaluation of psycho-pharmacological and psychotoxic actions of methylxanthines by ambulatory activity and discrete avoidance in mice. The Journal of toxicological sciences, 17(2), 81-90.
Martínez-Pinilla, E., Oñatibia-Astibia, A., & Franco, R. (2015). The relevance of theobromine for the beneficial effects of cocoa consumption. Frontiers in pharmacology, 6, 30.
Ranjitha, D., & Sudha, K. (2015). ALKALOIDS IN FOODS. International Journal of Pharmaceutical, Chemical & Biological Sciences, 5(4).
Reading, W. W. r. Caffeine vs. Chocolate: A Mighty Methyl Group.
Ruxton, C. (2008). The impact of caffeine on mood, cognitive function, performance and hydration: a review of benefits and risks. Nutrition Bulletin, 33(1), 15-25.