I pulled together this info last year as part of a forum discussion, but I keep wanting to refer people to it and the forum location is not so friendly for that. It’s just a compendium of what I dug up then, in an honest search for all the available evidence.
Here’s a recent review article: http://www.informaworld.com/smpp/content~db=all~content=a742127085
The story, as always, is more complicated than simply ‘coffee good’ or ‘coffee bad’. Coffee helps with some things and harms others. A decision about its use would involve all of a person’s other risk factors like diet, exercise, heredity and so on.
Here’s my list of 10 recent scholarly peer reviewed papers on the benefits of coffee along with brief quotes of their findings:
“From the data presented here, it is concluded that only heavy consumption (>6 cups/day) of boiled unfiltered coffee is harmful to the heart as a result of the dose-related plasma cholesterol and LDL increase due to the diterpene oils. Although epidemiological studies show that moderate consumption of this coffee appears to confer some cardiovascular benefit. …moderate filtered coffee consumption, which is the usual pattern of the many of the subjects in the populations studied, is recommended.”
Jennifer Stella Bonitaa, Michael Mandaranoa, Donna Shutaa and Joe Vinson (2007). Coffee and cardiovascular disease: In vitro, cellular, animal, and human studies. Pharmacological Research
Volume 55, Issue 3: 187-198.
“This study confirms a striking protective effect of caffeinated coffee against incident diabetes and extends these findings to incident diabetes based on OGTT independent of multiple plausible confounders.”
Besa Smith, MPH, Deborah L. Wingard, PHD, Tyler C. Smith, MS, Donna Kritz-Silverstein, PHD and Elizabeth Barrett-Connor, MD. (2006. Does Coffee Consumption Reduce the Risk of Type 2 Diabetes in Individuals With Impaired Glucose? Diabetes Care. 29(11): 2385-2390.
“Regular coffee consumption was not associated with an increased mortality rate in either men or women. The possibility of a modest benefit of coffee consumption on all-cause and CVD mortality needs to be further investigated.”
Esther Lopez-Garcia, PhD; Rob M. van Dam, PhD; Tricia Y. Li, MD; Fernando Rodriguez-Artalejo, MD, PhD; and Frank B. Hu, MD, PhD. (2008). The Relationship of Coffee Consumption with Mortality. Annals of Internal Medicine, 148(12): 904-914.
“A reliable tool for measurement of caffeine consumption demonstrated that caffeine consumption, particularly from regular coffee, above a threshold of approximately 2 coffee-cup equivalents per day, was associated with less severe hepatic fibrosis.”
Modi AA, Feld JJ, Park Y, Kleiner DE, Everhart JE, Liang TJ, Hoofnagle JH. (2010). Increased caffeine consumption is associated with reduced hepatic fibrosis. Hepatology, 53(1): 207-208.
“Long-term coffee consumption was not associated with an increased risk of stroke in women. In contrast, our data suggest that coffee consumption may modestly reduce risk of stroke.”
Esther Lopez-Garcia, PhD; Fernando Rodriguez-Artalejo, MD, PhD; Kathryn M. Rexrode, MD, MPH; Giancarlo Logroscino, MD, PhD; Frank B. Hu, MD, PhD; Rob M. van Dam, PhD. (2009). Coffee Consumption and Risk of Stroke in Women. Circulation, 119: 1116-1123.
“The increase in GCSF is particularly important because long-term treatment with coffee (but not decaffeinated coffee) enhanced working memory in a fashion that was associated only with increased plasma GCSF levels among all cytokines. Since we have previously reported that long-term GCSF treatment enhances cognitive performance in AD mice…”
Chuanhai Cao, Li Wang, Xiaoyang Lin, Malgorzata Mamcarz, Chi Zhang, Ge Bai, Jasson Nong, Sam Sussman, Gary Arendash. (2011). Caffeine Synergizes with Another Coffee Component to Increase Plasma GCSF: Linkage to Cognitive Benefits in Alzheimer’s Mice. Journal of Alzheimer’s Disease, DOI: 10.3233/JAD-2011-110110.
“The combined effect of coffee and mental stress significantly decreased diastolic blood pressure (Delta8 mm Hg) and increased heart rate (Delta6 beats per minute) and mental alertness (Delta67.3%) in caffeine-naive and caffeine-habituated females, whereas systolic blood pressure (Delta10.3 mm Hg) only increased in the caffeine-naive participants.”
Michael D. Kennedy, Ashley V. Galloway, Leanne J. Dickau and Megan K. Hudson. (2008). The cumulative effect of coffee and a mental stress task on heart rate, blood pressure, and mental alertness is similar in caffeine-naïve and caffeine-habituated females. Nurtition Research, 28(9): 609-614.
“Our findings do not support the hypothesis that coffee consumption increases the long-term risk of coronary heart disease. Habitual moderate coffee drinking was associated with a lower risk of CHD in women.”
Jiang-nan Wu, Suzanne C Ho, Chun Zhou, Wen-hua Ling, Wei-qing Chen, Cui-ling Wang and Yu-ming Chen (2008). Coffee consumption and risk of coronary heart diseases: A meta-analysis of 21 prospective cohort studies. International Journal of Cardiology, Volume 137, Issue 3, Pages 216-225.
“In acute studies involving AD [Alzheimer’s disease] mice, one oral caffeine treatment quickly reduced both brain and plasma Abeta levels – similarly rapid alterations in plasma Abeta levels were seen in humans following acute caffeine administration. “Caffeinated” coffee provided to AD mice also quickly decreased plasma Abeta levels, but not “decaffeinated” coffee, suggesting that caffeine is critical to decreasing blood Abeta levels. Caffeine appears to provide its disease-modifying effects through multiple mechanisms, including a direct reduction of Abeta production through suppression of both beta- and gamma-secretase levels. These results indicate a surprising ability of moderate caffeine intake (the human equivalent of 500 mg caffeine or 5 cups of coffee per day) to protect against or treat AD in a mouse model for the disease and a therapeutic potential for caffeine against AD in humans.”
Gary W. Arendash, Chuanhai Cao. (2010). Caffeine and Coffee as Therapeutics Against Alzheimer’s Disease. DOI: 10.3233/JAD-2010-091249.
“Our data support an inverse association between coffee consumption and diabetes and suggest that the time of drinking coffee plays a distinct role in glucose metabolism.”
Daniela S Sartorelli, Guy Fagherazzi, Beverley Balkau, Marina S Touillaud, Marie-Christine Boutron-Ruault, Blandine de Lauzon-Guillain, and Françoise Clavel-Chapelon. (2010). Differential effects of coffee on the risk of type 2 diabetes according to meal consumption in a French cohort of women: the E3N/EPIC cohort study. American Journal of Clinical Nutrition, 91(4): 1002-1012.
There’s more, but that’s a decent place to start.