Coffee: A Selected Overview of Beneficial or Harmful Effects on the Cardiovascular System?

Abstract

With a history that began in 800 A.D., coffee is the most popular drink known and as a result, the issues regarding its physiologic effects deserve attention. Maintaining alertness is a wellknown benefit and in addition, the cardiovascular (CV) effects of the active compounds, which include polyphenols and caffeine, must be considered. Genetics are relevant and where slow caffeine metabolism is inherent, the risk of nonfatal myocardial (MI) has been shown to be increased. Overall risk for coronary heart disease (CHD) is not supported and unless there is excessive intake, congestive heart failure (CHF) is not adversely affected; in moderation, there may be some benefit for CHF. There is no apparent increased risk of sudden cardiac death (SCD). Overall, there also appears to be a beneficial inverse association with all-cause mortality, although this is not absolute for extra heavy intake. Benefit in reducing stroke also has supportive evidence. Hypertension is not increased by coffee. Boiled and unfiltered coffee appears to increase plasma cholesterol and triglycerides but for the overall metabolic syndrome, there appears to be benefit. There is also some evidence that paper-filtered coffee results in an increase in some markers of inflammation. Association of coffee with arrhythmias has been a major concern though in moderation it is not a significant overall problem. Therefore, only if a patient were to associate major arrhythmic symptoms with coffee would cessation have to be advised. Where coffee clearly shines from a CV standpoint is in the established decrease in onset of type 2 diabetes mellitus (DM). Any benefit or harm has always been attributed to caffeine as the apparent major component. However, coffee contains a myriad of compounds, including polyphenols. These other substances may be most relevant for potential benefit or harm and some of these may be partially removed or altered by coffee preparation methods such as paper filtration. Multiple studies support this by what appears to be no CV advantage or disadvantage for decaffeinated coffee. The bottom line on coffee, for those who enjoy the brew, is that it is a wonderful beverage with rare associated CV disadvantage and with much to recommend it from an overall CV standpoint.

Adherence to the 2015 Dutch dietary guidelines and risk of non-communicable diseases and mortality in the Rotterdam Study

“…Unfortunately, the items in the FFQs did not distinguish between filtered versus unfiltered coffee or salted versus unsalted nuts, which are important distinctions in the new dietary guidelines. This may have led to an underestimation of the magnitude of the associations for the outcomes that have been particularly associated with coffee and salt consumption in the previous literature such as cardiovascular disease, type 2 diabetes and dementia [ 36 – 38 ]. For some food groups, no quantitative cut-offs were provided in the dietary guidelines, e.g.…”

Caffeinated and decaffeinated coffee consumption and risk of all‐cause mortality: a dose–response meta‐analysis of cohort studies

“…Although the explicit mechanisms of the association of coffee consumption and all‐cause mortality remain unclear, several mechanisms have been proposed. Caffeine contained in the product coffee affects the cardiovascular system and central nervous system . Some studies found moderate caffeine consumption to be associated with a reduced risk of all‐cause mortality.…”

Habitualcaffeine Consumption and Its Influence on Myocardial Fibers, Blood Pressure and Oxidative Status in Pregnant Albino Wistar Rats.

“…Studies have reported caffeine to exhibit protective ability against cellular damage (Krisko et al, 2005), thus effective in preventing LDL oxidation (Lee, 2000), reduces MDA levels, augments the activities of hepatic catalase and superoxide dismutase (SOD) (Mukhopadhyay et al, 2003) and possess anti-inflammatory effect (Whayne, 2015;Chen et al,2010;Lvet al,2010). Others suggests that caffeine isable to induce certain forms of oxidativedamage by increasing lipopolysaccharide(LP) (Dianzani et al, 1991;Al Moutaery et al, 2003), increased MDA levelsin the livers of rats (Karas et al, 2001), reduced Na+/K+-ATPase activities and increased NO levels by raising the endothelial NOS expression in the kidneys (Umemura et al, 2006;Lee et al, 2002).…”