Moderate coffee intake may prevent certain types of premature death.
According to some estimates, 2.25 billion cups of coffee are consumed worldwide, daily.
Anything that humans consume on such a huge scale deserves thorough research into its health benefits, or lack thereof.
Coffee is a complex cocktail of chemicals, including, of course, naturally occurring caffeine. Alongside this much-studied and consumed stimulant are a whole host of interesting chemicals.
Coffee includes more than 1,000 distinct and exotic sounding compounds, including caffeoylquinic acids, chlorogenic acids, diterpenes, feruloylquinic acids, 4-methylimidazole and p-coumaroylquinic acids, to name but a few.
The highly abbreviated list above makes coffee's complex range of physiological effects less surprising. Is it good or bad for the heart? Positive or negative for liver function? Does it help or hinder Alzheimer's, or worsen the effects of diabetes?
New research reported in the American Heart Association's journal Circulation brings together data from a number of longitudinal trials to investigate coffee's potential health effects over a substantial period of time.
The investigation utilizes data from 74,890 women in the Nurses' Health Study and 93,054 from the Nurses' Health Study 2, plus 40,557 men from the Health Professionals Follow-up Study.
Information regarding dietary habits was collected from questionnaires every 4 years, with participants being followed up for a maximum of 30 years.
Coffee's health benefits
The study found that people who drank a moderate amount of coffee (fewer than five cups per day) experienced a lower risk of death from cardiovascular disease, neurological diseases, type 2 diabetes and suicide.
The study's lead author, Dr. Ming Ding, says:
Interestingly, the study included caffeinated and decaffeinated coffee, so at least some of the measured benefits of coffee appear to be secondary to the caffeine content.
The group also made sure to control for alcohol and tobacco consumption, as these were both relatively high in coffee drinkers, compared with non-coffee drinkers.
The authors make it clear that the study was not designed to show a direct causation between coffee drinking and illness, so drawing conclusions at this stage would be premature. Another drawback, mentioned by the research team, was their reliance on participants accurately reporting their own level of coffee consumption.
Previous results of similar studies have produced inconsistent results in regard to coffee's effects on various illnesses, so the results of this study cannot be taken as definitive evidence, but they are a significant addition to the literature.
Previous research into coffee's health benefits
In recent years, there has been a wide range of experimentation into the consequences of high coffee intake. Results seem to show coffee as having a positive role in type 2 diabetes, Parkinson's and some liver diseases.
On the other side of the coin, coffee appears to negatively impact blood pressure and plasma homocysteine, both of which increase cardiovascular risk, contrary to the current study's findings.
In addition, some sections of society are likely to be more vulnerable to adverse effects. Another of the study's authors, Dr. Frank Hu, adds another word of caution:
"Regular consumption of coffee can be included as part of a healthy, balanced diet. However, certain populations such as pregnant women and children should be cautious about high caffeine intake from coffee or other beverages."
The current study's results certainly are intriguing. Dr. Ding and his team hope that further research, over the years to come, will tease apart the roles of some of the individual ingredients within coffee.
As part of the ever-growing tapestry of information on coffee's health effects, Medical News Today recently covered research into how an evening coffee can disrupt our body clock.