Everything You Need To Know About The Effects Of Caffeine


What are the effects of caffeine? What are the caffeine facts? Let’s face it.. who doesn’t love a nice morning caffeine coffee! we get in a routine of making coffee an important part of our lives, but what are the benefits when it comes to performance & weight loss?. Caffeine basically comes from coffee beans, but can also be synthesized in a laboratory. Regardless of where you find the coffee, whether it’s from energy drinks, tea, supplements, coffee, it will always have the same structure. Recent studies have shown caffeine to have significant benefits when it comes to improving exercise performance with physical strength and endurance. Studies have also found that regular caffeine intake can lower the risk of certain diseases like Alzheimer’s, cirrhosis, and certain cancers.

Regular use of caffeine will generally lead to having less tolerance towards its effects. So if taken in large amounts regularly you will likely only have an anti-sleep type effect. This is an “insurmountable” tolerance, which means more caffeine will not overcome it. A month-long break from caffeine will reduce tolerance.

How Much Caffeine Should You Be Taking?

Generally speaking, caffeine doses will be very specific for each person, the dosage will depend on your current body composition, medical conditions, and your goals. For beginners you want to be starting on lower doses around 100mg, while athletes or anyone wanting to increase strength & performance will be aiming for higher doses of 500mg and above. Researchers will generally use a dosage range of 4-6mg/kg body weight. Caffeine can be supplemented in energy drinks, coffee, tea, and in pill form. Remember that if you are a heavy caffeine user (aren’t we all) you won’t have the same effects on performance as someone who hasn’t been using caffeine regularly.

What Are The Effects On Metabolic Rate & Weight Loss

When looking at caffeine usage on the metabolic rate of athletes and sedentary persons, the results were quite conflicting. One study using 4mg/kg body weight in high-level aerobic athletes, for example, marathon runners found that caffeine significantly increased metabolic rate more than sedentary persons, achieving 80kJ/kg/min for the 120 minutes after ingestion (athlete) vs. just under 60kJ/kg/min for sedentary, with no significant differences prior to testing. The dose in the previous study equated to an average of 280mg, and another study using 300mg found the opposite results and that sedentary persons had an increased response. Both studies measured O2 consumption at rest.

This heightening of the metabolic rate is fairly well studied, but as for a long term solution solely for weight loss, caffeine would not have significant results. However, one study that was divided into a 4-week low-calorie weight loss phase and a 3 months maintenance phase (supplemented with green tea catechins and caffeine noted that caffeine intake was associated with greater weight loss during the acute phase but was not significantly related to long-term weight loss at maintenance phases. If you aren’t sure how to set up a calorie meal plan which meets your training, nutrition, and body composition goals, be sure to check out the 28 Day Mind & Body Challenge, where you can learn to implement the correct supplement amounts, macronutrients and calorie requirements.

Keys To Remember About Caffeine

  • It’s important to remember high caffeine and certain diseases / health conditions can be harmful, you should always speak with your GP regarding any potential sight effects you are experiencing and prescription medication you are taking
  • Research has shown that the metabolic effects of caffeine intake may vary due to genetics
  • Caffeine is generally accepted for performance benefits with strength & endurance training, however would not be suitable as a “long-term” solution for weight loss
  • Remember if you train later in the evening, caffeine has a relatively long half-life of around (six hours), so if you have a dose around 6pm then you could still have this in your system at mid-night! Be wary with dosage amounts and timing.
  • Caffeine is very quickly absorbed through the gastrointestinal tract, and moves through cellular membranes with the same efficiency that it is absorbed and circulated to tissue.

Final Wrap Up

Although caffeine has been widely researched, and clear metabolic benefits have been identified for performance, it’s also been noted that some studies have shown conflicting data, and as caffeine is used so commonly in society, opinions will circulate. My advice for performance and metabolic benefits is to start on a low dose and choose your preferred source for caffeine, increase your dosage slowly.


  1. Womack CJ, et al. The influence of a CYP1A2 polymorphism on the ergogenic effects of caffeineJ Int Soc Sports Nutr. (2012)
  2. Frary CD, Johnson RK, Wang MQ. Food sources and intakes of caffeine in the diets of persons in the United StatesJ Am Diet Assoc. (2005)
  3. Arnaud MJ. The pharmacology of caffeineProg Drug Res. (1987)
  4. Bishop D. Dietary supplements and team-sport performanceSports Med. (2010)
  5. Desbrow B, et al. The effects of different doses of caffeine on endurance cycling time trial performanceJ Sports Sci. (2012)

Choose to reuse and ditch disposable with a BPA/BPF/BPS-free water bottle. Free shipping on orders over $60 + free returns.Shop CamelBak Water Bottles


Please enter your comment!
Please enter your name here