Coffee! This aromatic cup of dark brown liquid is a delight to the morning bleary eyed. It is without a doubt one of the most popular beverages enjoyed across the globe. And research around the potential benefits of moderate coffee consumption is growing.
“Woohoo” I hear you cry!
So, what are some of the reported benefits for consuming coffee long-term?
Long-term coffee consumption
Coffee has been thought of as a dietary bad guy. But by disassociating coffee consumption from smoking or lack of exercise, and separating coffee from other caffeinated beverages, some positive associations are being made. This may be because the coffee bean contains protective substances that act as antioxidants. Even the caffeine may provide some of the health benefits.3
Research has found for some people it may be protective and reduce risk for cardiovascular disease, type 2 diabetes, and cirrhosis of the liver.1;5;7
It is also thought to boost dopamine, noradrenaline and adrenaline, enhancing mood and energy!11;15 The boost in dopamine may be why it is found to be beneficial in Parkinson’s disease.14
Older research has correlated 2-3 cups of coffee with temporary (1-3hour) increase in calcium loss in the urine in post-menopausal women with low calcium intake.8;9 But more recently, a study has found no association;12 and a 2016 cross-sectional study out of Korea found moderate intake (up to 3 cups/day) may have bone protective effects in postmenopausal women,3 though excessive amounts (>300mg/day) ain’t great for the bones of older ladies.13
Whilst evidence grows for some benefits outweighing the risks, keep in mind that everyone has a different tolerance for an amount of coffee consumed. This varies greatly from person to person and may depend on many factors, for example, the health of your liver, your nervous system, or genetics.
Short-term impacts and tolerance
The short-term impacts of coffee – and caffeine – on the body include an increased heart rate, blood vessel constriction, and raised blood homocysteine and adrenalin.10 Considering this, those with anxiety, or at higher risk of heart disease and or with raised homocysteine levels may wish think twice about downing a long black.
It takes 4-6 hours on average to metabolise, via the liver, before being expelled in the urine. Though once again, this time, and any reactions caused, varies from person to person.
In fact, Harvard University has identified 8 specific genes involving the degree of impact by coffee on metabolism, its psychoactive effects, and possibly lipid and glucose metabolism,4 which can begin to explain why some people can handle the coffee effects better than others.
The caffeine factor
Caffeine is an important part of the coffee picture – one many of us lean on to get going in the morning!
However, do not think that if coffee is okay, that Red Bull or Coke are too. Coffee is ground from a bean, and packaged with a bunch of phenolic antioxidants that may in part be the purveyors of the purported health benefits.
Whilst coffee may not be the bad guy we once believed, what does the research say about how much should we be drinking?
How much is too much?
As to whether you can drink coffee every day – or several times a day – is different for each individual. As mentioned, everyone processes coffee at a different rate. Some may not tolerate coffee at all!
But more than 4 cups of brewed coffee a day and not-so-great side effects may begin to creep in.
On average a cup (around 250ml) of brewed coffee contains 95mg of coffee; a 30ml espresso shot contains on average of 64mg (this is a ‘single’ shot in Australia), with 100ml containing an average 194mg.6 But this can vary!
It seems that 300-400mg or more of caffeine in a day may be when adverse effects occur.15 And we must remember, much of evidence promoting the health benefits of coffee are largely from observational studies, with more specific research and trials still in early days.2
Everything in moderation
Aside from all of this, perhaps ask yourself WHY you drink the coffee?
If you are persistently tired and use coffee as a crutch to get through the day, maybe see your qualified healthcare practitioner. They can work with you to ascertain WHY you are feeling fatigued; because as great as coffee is, the underlying cause of the tiredness should be investigated – we shouldn’t be reaching for a brew to constantly prop us up. It may also further contribute to the weariness.
Each person is different with a different level of tolerance, so be aware of the body’s reactions when you drink coffee. Do you feel sweaty, shaky, or anxious? Do you crave sweets, feel your blood pressure rise, experience loose bowels, or have issues sleeping? If so, you may want to reduce the dose, drink only every other day, or cut it out altogether.
Green tea is popular as an alternative to coffee, offering a much smaller dose of caffeine, as well as other beneficial constituents such as l-theanine, which can have a wonderfully calming effect on the nervous system.
If you like and can tolerate coffee – enjoy! Drink in moderation and without sugar. And the better the quality of coffee (and milk if you choose to use it), the better the benefit.
By Angela Johnson (BHSc Nut. Med.)
- Bhupathiraju, SN, Pan, A, Manson, JE, Willett, WC, Dam, RM, & Hu, FB 2014, ‘Changes in coffee intake and subsequent risk of type 2 diabetes: three large cohorts of US men and women’, Diabetologia, no. 7, p. 1346.
- Cano-Marquina, A, Tarín, J, & Cano, A 2013, ‘Review: The impact of coffee on health’, Maturitas, vol. 75, pp. 7-21.
- Choi, E, Choi, K, Park, SM, Shin, D, Joh, H, & Cho, E 2016, ‘The Benefit of Bone Health by Drinking Coffee among Korean Postmenopausal Women: A Cross-Sectional Analysis of the Fourth & Fifth Korea National Health and Nutrition Examination Surveys’, PLoS ONE, vol. 11, no. 1, pp. 1-14.
- Cornelius, MC et. al 2015, ‘Genome-wide meta-analysis identifies six novel loci associated with habitual coffee consumption’, Molecular Psychiatry, 20, no. 5, pp. 647-56.
- Ding, M Bhupathiraju, SN, Satija, A, van Dam, RM, & Hu, FB 2014, ‘Long-term coffee consumption and risk of cardiovascular disease: a systematic review and a dose-response meta-analysis of prospective cohort studies’, Circulation, no. 6, p. 643.
- Food Standards Australia New Zealand 2010, Coffee, from ground coffee beans, espresso style, without milk’, NUTTAB 2010 Online Searchable Database, viewed 12 July 2016, <http://www.foodstandards.gov.au/science/monitoringnutrients/nutrientables/nuttab/Pages/default.aspx>
- Gallus, S, Tavani, A, Negri, E, & La Vecchia, C 2002, ‘Original article: Does Coffee Protect Against Liver Cirrhosis?’, Annals of Epidemiology, vol. 12, pp. 202-205.
- Gropper, SS & Smith, JL 2013, Advanced Nutrition and Human Metabolism, 6th, Wadsworth, Cengage Learning, Belmont CA.
- Harris, SS & Dawson-Hughes, B 1994, ‘Caffeine and bone loss in healthy postmenopausal women’, American Journal of Clinical Nutrition, 60, no. 4, pp. 573-578.
- Lopez-Garcia, E 2012, ‘Coffee consumption and risk of chronic diseases: changing our views’, The American Journal Of Clinical Nutrition, vol. 95, no. 4, pp. 787-788.
- Lucas, M, Mirzaei, F, Pan, A, Okereke, OI, Willett, WC, O’Reilly, ÉJ, Koenen, K, & Ascherio, A 2011, ‘Coffee, caffeine, and risk of depression among women’, Archives Of Internal Medicine, vol. 171, no. 17, pp. 1571-1578.
- Lloyd, T Johnson-Rollings, N Eggli, DF Kieselhorst, K Mauger, EA & Cusatis, DC 2000, ‘Bone status among postmenopausal women with different habitual caffeine intakes: a longitudinal investigation’ Journal of the American College of Nutrition, vol. 19, no. 2, pp. 256-261
- Rapuri, PB, Gallagher, JC, Kinyamu, HK, & Ryschon, KL 2001, ‘Caffeine intake increases the rate of bone loss in elderly women and interacts with vitamin D receptor genotypes’, The American Journal Of Clinical Nutrition, vol. 74, no. 5, pp. 694-700.
- Ross, GW, Abbott, RD, Petrovitch, H, Morens, DM, Grandinetti, A, Tung, KH, Tanner, CM, Masaki, KH, Blanchette, PL, Curb, JD, Popper, JS, & White, LR 2000, ‘Association of coffee and caffeine intake with the risk of Parkinson disease’, JAMA, vol. 283, no. 20, pp. 2674-2679.
- Ruxton, CS 2008, ‘The impact of caffeine on mood, cognitive function, performance and hydration: a review of benefits and risks’, Nutrition Bulletin, vol. 33, no. 1, pp. 15-25.