How Much Coffee Should I Drink Daily?


Coffee, believe it or not, may have more positive health benefits than you might think.

This may surprise you given that many reports have been published about how harmful coffee can be, but of course, ‘everything in moderation’ as the old adage goes.


Caffeine kick

There is of course the benefit of increasing energy levels and making you feel less tired due to the caffeine,1,2, the most commonly used psychoactive substance in the world3, but that’s pretty common knowledge. Drinking coffee gets caffeine into your bloodstream which then enters the brain,4 and once there it blocks an inhibitory neurotransmitter called Adenosine. After that, the amount of other neurotransmitters such as norepinephrine and dopamine actually increase, leading to enhanced firing of neurons. 5, 6

There have been many controlled trials in humans that show how coffee improves various aspects of brain function, including memory, mood, vigilance, energy levels, reaction times and general cognitive function.7, 8, 9

Fat burning

But, did you know that caffeine is found in almost every fat burning supplement? The reason for this is that coffee has been proven to help increase the metabolic rate by between 3 and 11%, which in turn speeds up the burning of fat and calories.10,11

Physical performance enhancer

Another interesting point is that caffeine can drastically improve physical performance by stimulating your nervous system, causing it to send signals to the fat cells to break down body fat 12, 13 and it also increases Epinephrine (Adrenaline) levels in the blood 14, 15 which is the “fight or flight” hormone, designed to make our bodies ready for intense physical exertion.

Beneficial nutrients

Another positive fact about coffee is that it contains a whole host of nutrients, each of which has its own particular benefits. A single cup of coffee contains the following 16:

  • Riboflavin (Vitamin B2): 11% of the RDA.
  • Pantothenic Acid (Vitamin B5): 6% of the RDA.
  • Manganese and Potassium: 3% of the RDA.
  • Magnesium and Niacin (B3): 2% of the RDA.


Considering type 2 diabetes is such an enormous worldwide health problem currently afflicting about 300 million people, it’s also very good to know that coffee may lower your risk of type 2 diabetes which is characterized by elevated blood sugars in the context of insulin resistance or an inability to secrete insulin. For some reason, coffee drinkers have a significantly reduced risk of developing type 2 diabetes as has been shown in studies of people who drink the most coffee have a 23-50% lower risk of getting this disease, one study showing a reduction as high as 67%. 17-21

Alzheimer’s and dementia

A perhaps slightly surprising potential benefit from coffee is its potential to protect against Alzheimer’s Disease and Dementia.

Alzheimer’s disease is the most common neurodegenerative disease and the leading cause of dementia worldwide, normally affecting people over 65 years old and without a known cure. There are plenty of guides on healthy eating and exercising to try to minimize the risk, but it has been shown in tests that coffee drinkers have up to a 65% lower risk of developing Alzheimer’s. 22,23

Parkinson’s disease

Another disease which is widespread and debilitating, usually also in the older age group, is Parkinson’s disease: the second most common neurodegenerative disease after Alzheimer’s and is caused by the death of dopamine-generating neurons in the brain. As with Alzheimer’s, there is no known cure, which makes it that much more important to focus on prevention. Interestingly, studies have shown that coffee drinkers (caffeinated, not de-caffeinated) have a much lower risk of developing Parkinson’s disease, with a reduction in risk ranging from 32-60%. 24-27

Liver disease

Coffee, it would seem, also has protective effects on the Liver. An incredibly important organ which is often subject to several common diseases, including hepatitis, fatty liver disease and others, many of which can lead to a condition called cirrhosis, in which the liver has been largely replaced by scar tissue. According to several studies, coffee may protect against cirrhosis with people who drink 4 or more cups per day having up to an 80% lower risk. 28-30


Depression is a serious mental disorder that causes a significantly reduced quality of life and is incredibly common, with about 4.1% of people in the U.S. currently meeting the criteria for clinical depression. In a Harvard study published in 2011, women who drank 4 or more cups per day had a 20% lower risk of becoming depressed. 31 A further study which included 208,424 individuals found that those who drank 4 or more cups per day were 53% less likely to commit suicide. 32


When it comes to diseases, it seems coffee has far more benefits than we could have imagined, with cancer being another hideous disease which coffee might be able to help with. Coffee appears to be protective against at least two types of cancer: liver cancer and colorectal cancer, though some have claimed it protects against 10 different types of cancer. Liver cancer is the third leading cause of cancer death in the world, while colorectal cancer ranks fourth. 33 Studies show that coffee drinkers have up to a 40% lower risk of liver cancer 34,35, whilst one study showed that those who drank 4-5 cups of coffee per day had a 15% lower risk of colorectal cancer. 36

Heart disease and blood pressure

There have often been claims that caffeine can increase blood pressure, which is actually true, but the effect is very small (3-4 mm/Hg) and usually disappears if you drink coffee regularly. However, it may be that it can cause increased blood pressure in some people so bear that in mind if you have elevated blood pressure. Studies do not support the myth that coffee raises the risk of heart disease, on the contrary in fact, there is some evidence that women who drink coffee have a reduced risk of heart disease and some studies have shown that coffee drinkers actually have a 20% lower risk of stroke. 37-40


So, based on the above advantages and studies, given that coffee drinkers are less likely to get many diseases, it makes sense that coffee could help you live longer. There are actually several observational studies showing that coffee drinkers have a lower risk of death, two of which associated coffee drinkers with a 20% lower risk of death in men and a 26% lower risk of death in women, over a period of 18-24 years. 41

How much can you safely drink?

It has to be noted here that each person reacts differently to and can tolerate different amounts of coffee, but as a guideline; the caffeine content in a cup of coffee is highly variable, ranging from 50 to 400+ mg per cup. A small home-brewed cup of coffee could contain 50 mg, while a big 16 oz Starbucks grande can contain over 300 mg. As a general rule, you can assume that an average 8 ounce cup of coffee contains around 100 mg of caffeine.

Several sources suggest that 400 mg of caffeine, or 4 cups of coffee, are safe for most healthy adults 42,43 however, many people drink much more than that without any issues.
It should also be noted that most of the benefits are related to the caffeine in coffee, so this would obviously not be applicable in the case of decaffeinated coffee.
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4. Blood-brain barrier transport of caffeine: Dose-related restriction of adenine transport – A.L. McCall 1, W.R. Millington 2, R.J. Wurtman
5. Adenosine, Adenosine Receptors and the Actions of Caffeine- Bertil B. Fredholm
6. Brain Res Brain Res Rev. 1992 May-Aug;17(2):139-70. Caffeine and the central nervous system: mechanisms of action, biochemical, metabolic and psychostimulant effects.: Nehlig A1, Daval JL, Debry G.
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9. The effects of low doses of caffeine on human performance and mood – H. R. Lieberman, R. J. Wurtman, G. G. Emde, C. Roberts, I. L. G. Coviella
10. Normal caffeine consumption: influence on thermogenesis and daily energy expenditure in lean and postobese human volunteers. – Am J Clin Nutr 1989 49: 1 44-50
11. Ann Nutr Metab. 1995;39(3):135-42.Comparison of changes in energy expenditure and body temperatures after caffeine consumption.- Koot P1, Deurenberg P.
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13. Effect of caffeine on the metabolic responses of lipolysis and activated sweat gland density in human during physical activity – Tae-Wook Kim, Young-Oh Shin, Jeong-Beom Lee , Young-Ki Min, Hun-Mo Yang
14. Med Sci Sports Exerc. 1994 Apr;26(4):453-8.Effects of caffeine on the metabolic and catecholamine responses to exercise in 5 and 28 degrees C.- Anderson DE1, Hickey MS.
15. Caffeine Can Decrease Insulin Sensitivity in Humans- Gerben B. Keijzers, MD1, Bastiaan E. De Galan, MD1, Cees J. Tack, MD1 and Paul Smits, MD12
17. Coffee and tea consumption and risk of type 2 diabetes- S. van Dieren, C. S. P. M. UiterwaalAffiliated with Julius Centre for Health Sciences and Primary Care, University Medical Centre Utrecht, Y. T. van der Schouw, D. L. van der A, J. M. A. Boer, A. Spijkerman, D. E. Grobbee, J. W. J. Beulens
18. Coffee, tea, and incident type 2 diabetes: the Singapore Chinese Health Study1,2,3 – Andrew O Odegaard, Mark A Pereira, Woon-Puay Koh, Kazuko Arakawa, Hin-Peng Lee, and Mimi C Yu
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20. offee consumption and risk of type 2 diabetes mellitus – Rob M van Dam, MSca, , , Edith JM Feskens, PhDa
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22. Does caffeine intake protect from Alzheimer’s disease?- L. Maia andA. De Mendonça: Version of Record online: 3 JUL 2002
23. Caffeine intake and dementia: systematic review and meta-analysis.-Santos C1, Costa J, Santos J, Vaz-Carneiro A, Lunet N.
24. A meta-analysis of coffee drinking, cigarette smoking, and the risk of Parkinson’s disease – Miguel A. Hernán MD, DrPH1,*, Bahi Takkouche MD, PhD2, Francisco Caamaño-Isorna PharmD2 andJuan J. Gestal-Otero MD, PhD2
25. Coffee and tea consumption and the risk of Parkinson’s disease – Gang Hu MD, PhD1,2,†,*, Siamak Bidel MD1,2,†, Pekka Jousilahti MD, PhD1,3, Riitta Antikainen MD, PhD4 andJaakko Tuomilehto MD, PhD1,2,5
26. Parkinson Disease – G. Webster Ross, MD; Robert D. Abbott, PhD; Helen Petrovitch, MD; David M. Morens, MD; Andrew Grandinetti, PhD; Ko-Hui Tung, MS; Caroline M. Tanner, MD, PhD; Kamal H. Masaki, MD; Patricia L. Blanchette, MD, MPH; J. David Curb, MD, MPH; Jordan S. Popper, MD; Lon R. White, MD, MPH
27. Prospective study of caffeine consumption and risk of Parkinson’s disease in men and women – Alberto Ascherio MD, DrPH1,2,*, Shumin M. Zhang MD, ScD1,3, Miguel A. Hernán MD, DrPH2, Ichiro Kawachi MD, PhD3,4, Graham A. Colditz MD, DrPH2,3, Frank E. Speizer MD3,5 andWalter C. Willett MD, DrPH1,2,3
28. Coffee, cirrhosis, and transaminase enzymes.- Klatsky AL1, Morton C, Udaltsova N, Friedman GD.
29. Does coffee protect against liver cirrhosis?- Gallus S1, Tavani A, Negri E, La Vecchia C.
30. Coffee, caffeine, and the risk of liver cirrhosis.- Corrao G1, Zambon A, Bagnardi V, D’Amicis A, Klatsky A; Collaborative SIDECIR Group.
31. Coffee, Caffeine, and Risk of Depression Among Women- Michel Lucas, PhD, RD; Fariba Mirzaei, MD, MPH, ScD; An Pan, PhD; Olivia I. Okereke, MD, SM; Walter C. Willett, MD, DrPH; Éilis J. O’Reilly, ScD; Karestan Koenen, PhD; Alberto Ascherio, MD, DrPH
32. A Prospective Study of Coffee Drinking and Suicide in Women – Ichiro Kawachi, MD; Walter C. Willett, MD; Graham A. Colditz, MD; Meir J. Stampfer, MD; Frank E. Speizer, MD: Arch Intern Med. 1996;156(5):521-525. doi:10.1001/archinte.1996.00440050067008.
34. Coffee Consumption and Risk of Liver Cancer: A Meta-Analysis- Susanna C. Larsson, , Alicja Wolk
35. Coffee consumption and the risk of primary liver cancer: Pooled analysis of two prospective studies in Japan – Taichi Shimazu1,†,*, Yoshitaka Tsubono2, Shinichi Kuriyama1, Kaori Ohmori1, Yayoi Koizumi1, Yoshikazu Nishino1, Daisuke Shibuya3 andIchiro Tsuji1
36. Caffeinated and decaffeinated coffee and tea intakes and risk of colorectal cancer in a large prospective study1,2,3,4 – Rashmi Sinha, Amanda J Cross, Carrie R Daniel, Barry I Graubard, Jennifer W Wu, Albert R Hollenbeck, Marc J Gunter, Yikyung Park, and Neal D Freedman
37. Genetic determinants of blood pressure responses to caffeine drinking. – Renda G1, Zimarino M, Antonucci I, Tatasciore A, Ruggieri B, Bucciarelli T, Prontera T, Stuppia L, De Caterina R.
38. Blood Pressure Response to Caffeine Shows Incomplete Tolerance After Short-Term Regular Consumption – William R. Lovallo, Michael F. Wilson, Andrea S. Vincent, Bong Hee Sung, Barbara S. McKey, Thomas L. Whitsett
39. Coffee Consumption and Coronary Heart Disease in Men and Women – A Prospective Cohort Study: Esther Lopez-Garcia, DrPH; Rob M. van Dam, PhD; Walter C. Willett, MD, DrPH; Eric B. Rimm, ScD; JoAnn E. Manson, MD, DrPH; Meir J. Stampfer, MD, DrPH; Kathryn M. Rexrode, MD, MPH; Frank B. Hu, MD, PhD
40. The Impact of Green Tea and Coffee Consumption on the Reduced Risk of Stroke Incidence in Japanese Population – The Japan Public Health Center-Based Study Cohort: Yoshihiro Kokubo, MD, PhD, FAHA, Hiroyasu Iso, MD, PhD, Isao Saito, MD, PhD, Kazumasa Yamagishi, MD, PhD, Hiroshi Yatsuya, MD, PhD, Junko Ishihara, PhD, Manami Inoue, MD, PhD and Shoichiro Tsugane, MD, PhD
41. The Relationship of Coffee Consumption with Mortality – Esther Lopez-Garcia, PhD; Rob M. van Dam, PhD; Tricia Y. Li, MD; Fernando Rodriguez-Artalejo, MD, PhD; and Frank B. Hu, MD, PhD
42. Coffee and health: a review of recent human research.- Higdon JV1, Frei B.
43. Effects of caffeine on human health. – Nawrot P1, Jordan S, Eastwood J, Rotstein J, Hugenholtz A, Feeley M.

J.D. Phillips
J.D. Phillips Runs and is a contributer to and lives with his family in Southern California.

When he's not online, he's usually found hiking or in the gym!