What is caffeine?
Caffeine is a natural stimulant, affecting multiple systems in the body including the central nervous system, respiratory system, digestive system and cardiovascular system. As a result caffeine is found to increase alertness, elevate mood, reduce tiredness, as well as reduce appetite and increase fat metabolism.
How does caffeine affect weight loss?
In 2023 a systemic review, published in The Journal of Sport Nutrition and Exercise Metabolism, explored the effects of caffeine on fat metabolism. The researchers found that caffeine enhances the rate of fat oxidation (the mechanism responsible for breaking down fat for energy) during physical activity and can help to support sustained weight loss. They also found that caffeine mildly elevates the body’s resting metabolism which can further support weight loss goals, when in a calorie deficit.
Th researchers identified the following key takeaways:
- Caffeine amplifies fat metabolism: Caffeine is as an enhancer of fat metabolism, yielding a significant but modest effect, mostly independent of individual factors including gender, fitness level, and caffeine dosage.
- Rest and exercise benefits: While the impact of caffeine on fat metabolism is evident under both rest and exercise conditions, its efficacy appears more pronounced during rest.
- Optimal dosage: Aim for doses greater than 3.0mg/kg of body weight, ideally ranging between 3.1 to 7.0mg/kg, to maximise caffeine’s metabolic effects. This is typically somewhere between 200mg to 400mg of caffeine per day, which equates to two to four regular cups of coffee.
- Strategic timing: Consume caffeine 30 to 75 minutes prior to exercise for peak effectiveness in promoting fat oxidation. NB be mindful of when you consume caffeine in relation to your bedtime!
Adding caffeine to your routine can help support weight loss, not just by slightly elevating metabolism but also by reducing appetite, and enhancing workout performance and motivation. However, caffeine is certainly not the primary driver for weight loss. It is simply a very small part of the jigsaw puzzle. The primary driver for weight loss is ensuring you are in a calorie deficit (3-500 calories a day is often a good start point). In order to ensure your weight loss is healthy, you’ll also want to include resistance training to preserve muscle mass, consume your calories from nutritious food sources, keep well hydrated and give yourself enough sleep to allow your body time to adapt and evolve.
Focus on the big ticket items and experiment with caffeine using the dosages above to help support your weight loss goals.
Sources:
Collado-Mateo, D., Lavín-Pérez, A. M., Merellano-Navarro, E., & Coso, J. D. (2020). Effect of Acute Caffeine Intake on the Fat Oxidation Rate during Exercise: A Systematic Review and Meta-Analysis. Nutrients, 12(12), 3603. https://doi.org/10.3390/nu12123603 Conger, S.
A., Tuthill, L. M., & Millard-Stafford, M. L. (2023). Does Caffeine Increase Fat Metabolism? A Systematic Review and Meta-Analysis. International Journal of Sport Nutrition and Exercise Metabolism, 33(2), 112-120. Retrieved Apr 3, 2024, from https://doi.org/10.1123/ijsnem.2022-0131
