This varies dramatically from person to person, but caffeine’s long half-life means that late-day doses can easily persist into the night and affect the quality of your sleep. The most important and common side-effect of caffeine is sleep disruption. The method of consumption can have impacts, though: coffee, for instance, is a well-known gastrointestinal irritant. Caffeine can have diuretic-like effects if you are not used to it, but among people who consume it regularly it does not seem to hinder hydration. Interestingly, the common perception of caffeine as a diuretic seems mostly incorrect. Use moderation in how much caffeine you consume, and take vitamins and supplements at least an hour apart from caffeine to reduce unwanted interactions. Luckily, impacts are short-term and reduced at lower doses. It also affects the body’s metabolism of calcium, Vitamin D, B-vitamins, and Manganese, among others. Most notably for athletes, it can temporarily reduce Iron absorption by up to 90%. Large doses can be fatal, and while this is unlikely with beverages it’s possible with tablets or powdered caffeine.Ĭaffeine can hinder uptake of certain nutrients. According to the Mayo Clinic, over 400 mg a day can cause headaches, insomnia, upset stomach, and anxiety, and 14% of Americans drink this much caffeine regularly. Like any psychoactive substance, caffeine does some undesirable things too. Source: Center for Science in the Public Interest Caffeine Content of Common Products Beverage/Product Type There’s a good chance you consume a performance-enhancing amount of caffeine every morning without even realizing it. This is actually a relatively “normal” dose, equivalent to a cup or two of Starbucks coffee for most people.
![caffeine half life caffeine half life](https://www.nejm.org/na101/home/literatum/publisher/mms/journals/content/nejm/2020/nejm_2020.383.issue-4/nejmra1816604/20200717-01/images/img_medium/nejmra1816604_f1.jpeg)
A study of cyclists riding 10k time trials found that depending on the rider’s gene variation, some athletes improved their time with caffeine by as much as 6.8%, some experienced no effects, and others experienced a 13.7% decrease in performance!ĭespite WADA’s former ban on high doses, most athletes experience the strongest ergogenic effect with about 3 – 6 mg of caffeine/kg of body weight. However, like caffeine’s effects generally, this is also genetically-determined. Some studies show no improvement in maximal efforts, but most show at least some measurable impact on endurance, averaging around 3%. Although it’s no longer banned, caffeine consumption is still monitored by WADA.Įxactly how much caffeine improves athletic performance varies. The World Anti Doping Agency even banned high levels of caffeine from competition between 1984- 2004.
![caffeine half life caffeine half life](https://66.media.tumblr.com/bb670b3ff1b01f15898136e58cc6127c/tumblr_nijs5oRBrD1r4g6x9o1_640.png)
How Caffeine Can Enhance Athletic PerformanceĬaffeine’s effects on athletic performance are well-acknowledged. Half-lives of 2 to 12 hours have been recorded, meaning some individuals may take up to 6x longer to clear caffeine from their systems than others! 6 hours seems about average, meaning most people still have 1/2 their coffee’s caffeine circulating in their blood 6 hours after drinking it, and ¼ still present after 12 hours. Drowsiness, headaches, irritability, and lack of focus are common results of caffeine withdrawal, familiar to any regular coffee drinker who stops cold turkey.Ĭaffeine’s impact and the pace at which the body metabolizes it are highly dependent on genetics. Likewise, suddenly ceasing consumption has noticeable effects. It also stimulates some secondary effects such as elevated heart rate and mild euphoria.Ĭaffeine commonly triggers tolerance with regular use. Caffeine acts as an adenosine antagonist, binding to and temporarily blocking these receptors from activating.
![caffeine half life caffeine half life](https://i.pinimg.com/736x/4b/3e/8f/4b3e8fdfcc85855cac0c92fa1cb9d7de.jpg)
Under normal circumstances, metabolism of ATP causes adenosine to gradually accumulate in receptors in the brain, eventually resulting in drowsiness.