Coffee has long been considered a drug, a dependency of the weak willed. Those of us who can t function before our morning fix are looked down upon. Some religions even restrict or forbid it. The rumors of what it does to your heart or your height or your life span makes even the most dedicated followers of joe try to restrain their intake. But now the science on coffee is starting to shine through and it s illuminating a whole world of health benefits.
In terms of cardiovascular health, one large meta-analysis of over a million participants, found that moderate drinkers (3-5 cups a day) appeared to have significantly less risk of cardiovascular disease compared to other participants. Another study found the same was true for moderate consumption and heart failure. Evidence also backs up a similar story for strokes.
It also appears that excessive coffee intake doesn t do too much damage. In the meta-analysis of cardiovascular disease, consumers of 5 or more cups a day had the same risk for cardiovascular disease as non-drinkers. Furthermore, participants in the aforementioned heart failure study needed 10 cups a day to see a negative effects in their risk as compared to non-drinkers.
It s not just your heart that benefits from coffee intake; it also may protect against various cancers. Several studies have found a 40 percent decrease in liver cancer incidence amongst coffee drinkers and another meta-analysis found that incidence of all cancer types was significantly reduced for coffee drinkers, and this was found to be a dose-dependent relationship (the more coffee you drank the lower your cancer incidence was). Other studies have found that coffee consumption does not affect prostate or breast cancer risk.
Beyond cancer coffee may also be linked to a decreased incidence of Parkinson's, type 2 diabetes and Alzheimer s disease. The diabetes study was a meta-analysis with over a million participants, and found a dose dependent relationship which was particularly pronounced when a person s intake reached 6-7 cups a day!
But the coup de grâce to the unhealthy myths about coffee are its apparent protection from death. Two separate meta-analyses both consisting of a million participants found that coffee intake was associated with reduced all cause mortality.
One important thing to point out here is that all the health benefits are associated with black coffee, so your frappuccino, double pump caramel latte, 3 sugars-5 creams, or regular coffee (if you re from Boston) are not associated with these positive effects. Also, we aren t talking about caffeine either, there is some aspect of brewing coffee beans that appears to bestow upon its drinker these beneficial effects.
As an avid devotee to the brew, this is music to my ears. However, even I feel the need to point out that these are epidemiological studies. None have yet shown a biological mechanism nor has anyone performed a clinical double blind study to really show whether these effects are real or data artifacts. On the other hand, the sheer number of these studies and the volume of their sample sizes does lend a lot of credence to their legitimacy.