|Image 1: If they are not laden with pesticides and anti-fungals, the small brown beans from the coffee pant can easily compete with green, black oolong and pu-erh teas, when it comes to countering the unwanted side-effects of the "holiday diet"|
Well, guess what, dear green tea connoisseurs, it may well be that (organic) coffee beans are in no way inferior to the unquestionably healthy, yet recently slightly over-hyped unoxidized camellia sinensis leaves. At least this is what a soon to be published study by Yuji Matsuda and his colleagues from the Nagoja University in Japan would suggest (Matsuda. 2011).
Tea or coffee during the holiday season - only a matter taste?
Matsuda et al. put a group of 8-week old mice on a pro-diabetic high-fat diet (this is the type of "high fat diet" that is high both in fat and in carbs and thusly is a perfect image of what 75% of the people are "eating" in the holiday season ;-). In the course of the 17-week study period the mice received either regular drinking water, or 2.5x diluted coffee, or water that was laced with 200mg of caffeine per liter (with a water intake of 13-14g/100g BW this would translate to a daily dose of 2.8mg/100mg and a human equivalent of 2.3mg/kg, or 182mg of caffeine per day for an 80kg human being). The intention was to investigate whether the results of epidemiological studies by van Dam (2002; 2005), Huxley (2009) and Goto (2011), which suggest that regular coffee consumption is associated with a profoundly reduced risk of developing metabolic syndrome or type II diabetes, could be replicated in a laboratory setting.
|Figure 1: Body weight at the beginning and end of the study period in the control group and the mice receiving 2.5x dilluted coffee or 200mg/L caffeine in their drinking water; food intake in g per 100g of body weight (data adapted from Matsuda. 2011).|
|Figure 2: Fat weight in mice after 17 weeks on high fat diet with either water, 2.5x diluted coffee or water + 200mg caffeine per L (data adapted from Matsuda. 2011).|
Time and again: Whole foods, or drinks, outperform extracts
If you take a closer look you will notice that despite a general tendency towards lower body fat levels in the coffee and caffeine group, the "whole food", or I should say, "whole beverage" has a much more pronounced effect on the "bad" visceral (epididymal) fat depots. So, just in case you still like your pills, caps and powders: This is only the latest in a long line of foods (this is the stuff that is not sold in caps or powder form) with verified health benefits, where one isolated compound, of which we believe that it is the "active ingredient" turns less potent than the whole food - so, could it possibly be that Nature knows best?
|Figure 3: Reductions in inflammatory cytokine (MCP-1, TNF-alpha, IL-6) and adipokine expression in the epididymal fat pads of mice receiving 2.5x diluted coffee or water laced with 200mg/L caffeine in addition to their high fat diet (data calculated based on Matsuda. 2011).|
|Figure 4: Insulin response (area under the curve in mg * min / dl) during glucose tolerance at different time-points during the 17-week study period (data calculated based on Matsuda. 2011).|
Coffee or tea? The choice is up to thee!
Since a direct comparison of the data from yesterday's tea study on teas would not be valid, anyways, and because I do not want to disturb the pre-Chrismas harmony and provoke a war between coffee and tea drinkers in the comment area of this blogpost, I would just advice everyone to just decline the soda your relatives may be offering you over the holidays and stick to either tea or coffee... whatever you like better - and by the way, dehydration is neither an issue for the habitual tea nor the habitual coffee drinker (Grandjean. 2000)!