Coffee: A healthful indulgence?
Overall, coffee seems to be a benign-to-beneficial habit.
For example, moderate caffeine intake enhances concentration and focus … without, despite common but unfounded claims, taxing the adrenal glands.
Better yet, coffee is the average Americans' top source of beneficial polyphenol “antioxidants” … beating all other plant food and beverages combined.
While this exalted status stems from the dominance of refined, polyphenol-poor plant foods in the standard American diet, there's no doubt that coffee is extraordinarily rich in healthful polyphenols.
And it's pretty clear that coffee helps deter diabetes, as Dutch scientists reported six years ago:
“This systematic review supports the hypothesis that habitual coffee consumption is associated with a substantially lower risk of type 2 diabetes.” (van Dam RM et al. 2005)
What about heart health?
Last year, Chinese researchers who examined the evidence concluded, “Our findings do not support the hypothesis that coffee consumption increases the long-term risk of coronary heart disease.” (Wu JN et al. 2010)
Adding more reassurance, a recent evidence review found that coffee doesn't cause chronic high blood pressure (hypertension) to any significant extent (Zhang Z et al. 2011).
Coffee-drinking is also linked to reduced rates of Parkinson's disease, certain cancers, and suicide.
Increases in “silent”, non-symptomatic inflammation might be a concern, with some evidence suggesting that coffee causes them.
On the other hand, coffee is loaded with polyphenols believed to exert effects that curb inflammation by indirect, “nutrigenomic” influences over gene expression, so coffee may be a “wash” in terms of inflammation.
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