Coffee consumption and health: umbrella review of meta-analyses of multiple health outcomes
BMJ 2017; 359 doi: https://doi.org/10.1136/bmj.j5024 (Published 22 November 2017) Cite this as: BMJ 2017;359:j5024All rapid responses
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The umbrella review of coffee consumption and health by Poole et al. includes a gentle plea to consider a randomised controlled trial of coffee for chronic liver disease, and an interesting Focus Group section that indicates a clinical interest in this particular usage.[1] I for one hope that such a trial does result from this publication.
I was able to find one small (n=40) RCT of coffee, a 30 day cross-over study in Hepatitis C patients confirming beneficial effects on telomere length, 8-hydroxydeoxyguanosine, AST, ALT, and collagen, despite high viral load in coffee drinkers at baseline.[2]
Not included in the review of Poole et al was a meta-analysis of the many studies showing an association between coffee drinking and lower ALT, AST, and GGT.[3]
The BMJ editorial about this review mentioned that coffee is often consumed with sugar and unhealthy fats, without defining the latter. However it is, or should be, well-known that saturated fats such as beef tallow and cocoa butter are strongly hepatoprotective in animal models of alcoholic liver disease, while polyunsaturated fats such as corn oil and soy oil induce disease progression.[4] A trial of this effect in humans would also be very welcome, albeit it may be extremely difficult to carry out. It is notable that coffee in the cited RCTs elevated LDL cholesterol, yet it was associated with reduced rates of all cardiovascular outcomes in the prospective cohort studies.[1] This is a similar pattern to the relationship between saturated fat, LDL cholesterol, and cardiovascular disease in the PURE study, and demonstrates that LDL cholesterol does not reliably inform dietary effects on health in the same way that it informs statin efficacy.[5]
Thus, having cream in one's coffee may be not be a bad habit, after all, even if we should hold the cake.
[1] Coffee consumption and health: umbrella review of meta-analyses of multiple health outcomes. Published: 22 November 2017; BMJ 359 doi:10.1136/bmj.j5024
[2] Cardin R, Piciocchi M, Martines D, Scribano L, Petracco M, Farinati F. Effects of coffee consumption in chronic hepatitis C: a randomized controlled trial. Dig Liver Dis. 2013 Jun;45(6):499-504. doi: 10.1016/j.dld.2012.10.021. Epub 2012 Dec 11.
[3] Heath RD, Brahmbhatt M, Tahan AC, Ibdah JA, Tahan V. Coffee: The magical bean for liver diseases. World Journal of Hepatology. 2017;9(15):689-696. doi:10.4254/wjh.v9.i15.689.
[4] Kirpich IA, Miller ME, Cave MC, Joshi-Barve S, McClain CJ. Alcoholic Liver Disease: Update on the Role of Dietary Fat. Osna N, Kharbanda K, eds. Biomolecules. 2016;6(1):1. doi:10.3390/biom6010001.
[5] Mente A, Dehghan M, Rangarajan S et al. Association of dietary nutrients with blood lipids and blood pressure in 18 countries: a cross-sectional analysis from the PURE study. The Lancet Diabetes & Endocrinology. 2017;5(10)
Competing interests: No competing interests
Caffeine is an addictive stimulant and social lubricant that tricks and traps us by creating the fleeting euphoria of mental energy, but the sustained sickness of mental lethargy. The euphoria of mental energy and the sickness of mental lethargy are polar opposites that reinforce each other: the euphoria blinds us to the sickness, and the sickness makes us crave the euphoria. Perversely but predictably, caffeine creates, aggravates, and perpetuates the very sickness of mental lethargy that it falsely seems to cure, thus placing coffee, tea, and energy drinks in a bad light.
Competing interests: No competing interests
Re: Coffee consumption and health: umbrella review of meta-analyses of multiple health outcomes
When choosing to consume coffee or cocoa, we must also consider the health and living conditions of those who harvest beans in plantations.
Slave labour in those plantations is very common and people are forced to survive in deplorable conditions.
References
https://www.theguardian.com/global-development/2016/mar/02/nestle-admits...
https://danwatch.dk/en/you-may-be-drinking-coffee-grown-under-slavery-li...
http://time.com/4989574/modern-slavery-forced-labor-marriage/
https://www.theguardian.com/global-development/2017/sep/19/latest-figure...
Competing interests: No competing interests