When trying to be healthy, doctors and care providers will often recommend you cut out coffee. But, what’s the deal? Is it really bad for your health? This question can certainly spark passionate debates on either side for or against coffee, but ultimately, one should look at the research and hard evidence to make a final decision.
Based on the extent of research on coffee, caffeine and green tea, a common theme seems to be that those who regularly drink these beverages, experience some associated benefits. We all know that staying hydrated, especially with water, has its benefits. One study (6) has shown that over a 4-year survey, those who regularly drank water, coffee and teas experienced a slight decrease in weight. On the other hand, those who regularly consumed sugar-sweetened beverages like sodas and juices experienced weight gain over that same time period. While data from research is not completely conclusive, it does show an association of favorable adiponectin levels (a hormone related to weight control) and lower visceral fat (tummy fat) levels (5).
So, how is it that caffeinated drinks help control or lower weight? There’s two pieces to the equation. Caffeine, from beverages like coffee and green tea, has been shown to result in thermogenesis and increased fat oxidation. What does that mean? Thermogenesis literally means “generating heat”, which in terms of our body is related to burning energy or calories. This helps to maintain our energy expenditure or metabolism. Fat oxidation essentially relates to the usage of fat for energy or fat burning. Coffee and green tea contain caffeine but also compounds called polyphenols. Polyphenols are compounds found in a variety of plant foods and herbs that act as anti-oxidants and help prevent cell damage among other benefits (2). Some evidence even suggests that due to its anti-oxidative effects, coffee consumption can have protective effect on DNA from damage (1). These polyphenol compounds help initiate thermogenesis by stimulating the sympathetic nervous system (SNS), known as the “flight or fight” response. Green tea specifically has a particular group of polyphenols called catechins that have shown an even greater effect on thermogenesis through the SNS. This effect increases norepinephrine availability (an SNS neurotransmitter hormone) leading to increased energy expenditure (metabolism) and fat oxidation or burning (4). Therefore, those who drink coffee and green tea experience greater energy expenditure (faster metabolism) and fat loss in those who only drink coffee (4).
So, how should you take your coffee? I, personally, enjoy my coffee black, no sugar, no milk, no fancy additions. I enjoy the simple things, I guess. On the other hand, some coffee lovers only take their coffee with milk or cream (or whatever other version of “milk” there is these days). Mixing the two gives you a beautiful warm caramel brown color that is just as enticing as the smell of that cup of Joe. But if you’re like me and insist that coffee should be drank just as it is, you may have science to back you up! Some studies (4) have shown that proteins (casein) in milk can inhibit beneficial activity of catechin-polyphenols and limit their benefits. But, as with anything, the science on that is not consistent across the board and there is room for debate.
Another benefit to drinking coffee or caffeinated beverages, is improved performance during exercise, both endurance and power exercise performance. Consuming coffee or caffeine one hour before exercise with a content of 5 mg of caffeine per body weight in kg for has shown some slight benefits in exercise performance in terms of speed and power (3). So, in terms of application, to roughly calculate your intake of caffeine you would multiply your weight in pounds by 2.3 mg/lb. to find the recommended caffeine dose before performance. A typical 16-ounce cup of light roast at Starbucks contains about 350 mg of caffeine, which would do the job for someone between 140-155 lbs. of weight. Just remember, the darker the roast, the LESS caffeine it contains.
Leave a comment and let me know what you think! What has your experience been with coffee and weight loss or exercise performance? I'd love to hear your take.
(1) Bakuradze, T.; Boehm, N.; Janzowski, C.; Lang, R.; Hofmann, T.; Stockis, JP.; Albert, F.; …; Eisenbrand, G. (April 4, 2011). Antioxidant‐rich Coffee Reduces DNA Damage, Elevates Glutathione Status and Contributes to Weight Control: Results from an Intervention Study.
Molecular Nutrition and Food Research, 55 (5), pp. 793-797. https://doi-org.proxyau.wrlc.org/10.1002/mnfr.201100093.
(2) Gunnars, K. (Jan 17, 2018). 10 Proven Benefits of Green Tea. Retrieved from:
(3) Hodgson, Adrian B; Randell, Rebecca K; Jeukendrup, Asker E. (April 2013). The Metabolic and Performance Effects of Caffeine Compared to Coffee during Endurance Exercise. PLoS One, 8 (4). DOI: 10.1371/journal.pone.0059561.
(4) Hursel, R; Westerterp-plantenga, M S. (April 2010). Thermogenic Ingredients and Body Weight Regulation. International Journal of Obesity, 34 (4), pp. 659-669. DOI:10.1038/ijo.2009.299.
(5) Mure, Kanae; Maeda, Shinya; Mukoubayashi, Chizu; Mugitani, Kouichi; Iwane, Masataka; et al. (July 2013). Habitual Coffee Consumption Inversely Associated with Metabolic Syndrome-related Biomarkers involving Adiponectin. Nutrition, 29 (7/8), pp. 982-987. DOI: 10.1016/j.nut.2013.01.011.
(6) Pan, A; Malik, V S; Hao, T; Willett, W C; Mozaffarian, D; Hu, F B (Oct 2013). Changes in water and beverage intake and long-term weight changes: results from three prospective cohort studies. International Journal of Obesity, 37 (10), pp. 1378-1385. DOI:10.1038/ijo.2012.225.