The only way to get people going in the morning is that early rush of caffeine from a strong cup of coffee. Likewise, the only way to get me running in the morning is a shot of energy drink which also contains caffeine. One recent piece of research conducted by the home of the Huskies, Washington State University highlights a finding that caffeine from coffee and energy drinks are no different when it comes to its absorption and subsequent metabolism.
It is a long held belief that caffeine absorption is quicker and has a greater impact if the drink is actually cold compared to one that is hot. In some cases, it is thought that a very rapid amount of caffeine intake could be harmful. This is probably only the case though if caffeine is consumed in powder or tablet form.
The research team from the health sciences group of the WSU Colleges of Pharmacy, Medicine and Nursing assessed caffeine uptake in humans by looking at different ways of presenting coffee and energy drinks, and their rate of consumption. The study group was relatively small – twelve men and twelve women all aged between 18 and 30 years old. They were given either Red Bull (the energy drink) or Folgers Classic Roast coffee which contained 160 mg of caffeine in each dose. That level of caffeine is also the amount to be found in a typical 16 ounce energy drink or cup of freshly brewed coffee. No account appears to be taken of any other substances in each drink, the medium itself although every other factor was kept consistent.
The study was conducted as an open-label, group-randomized cross-over type. Coffee and the energy drink was given either hot or cold and the subjects were asked to drink each in either 2 or 20 minutes. The only condition not followed was hot coffee drunk in 2 minutes for perhaps obvious reasons. Having administered each dose, 10 serial plasma samples were taken and the caffeine content measured using liquid chromatography-mass spectrometry (LC-MS) coupled to non-compartmental pharmacokinetic analysis. Mean pharmacokinetic parameters were analysed statistically based on calculation of the levels.
The study found no difference in caffeine uptake from either type of drink irrespective of rate of consumption or the temperature of the beverage.
It probably shouldn’t be too surprising a result as caffeine is the same molecule whether it’s from coffee, an energy drink or tea. What is more interesting though is the solution the coffee is dissolved in, as a coffee drink has a very different composition to one which often contains sugar and various salts such as an energy drink. It would seem to dispel a myth about beverage temperature and the rate of consumption on how caffeine in absorbed and used in the body.
White Jr., J.R., Padowski, J.M., Zhong, Y., Chen, G., Luo, S., Lazarus, P., Layton, M.E., McPherson, S. (2016) Pharmacokinetic analysis and comparison of caffeine administered rapidly or slowly in coffee chilled or hot versus chilled energy drink in healthy young adults. Clin. Toxicology 54(4) pp. 308-312 DOI:10.3109/15563650.2016.1146740