Coffee
Approximately 75% of the US population aged ≥20 y reported drinking coffee; 49% reported drinking coffee daily[1].
Although coffee has very little nutrient content, it contributes ∼5% of the potassium intake in the United States, which is similar to vegetables (excluding potatoes), fruit, and 100% juices[2], and can have low but variable concentrations of fluoride[3].
There is evidence that, in healthy adults, moderate coffee consumption (4–5 cups/d or 946–1183 mL/d) has beneficial effects for a number of chronic diseases. A recent review evaluated the evidence from meta-analyses of observational studies and RCTs in adults relating to coffee intake and health outcomes[4]. Of 59 unique outcomes examined in 112 meta-analyses of observational studies, coffee was associated with a probable decreased risk of breast, colorectal, colon, endometrial, and prostate cancers; cardiovascular disease and all-cause mortality; Parkinson disease; and type 2 diabetes. Of 12 unique acute outcomes examined in 9 meta-analyses of RCTs, coffee was associated with a rise in serum lipids, but this result was affected by significant heterogeneity among the study designs and likely by coffee preparation methods. The authors concluded that the robustness of many of the results indicated that coffee can be part of a healthful diet. In part, the beneficial effects could be due to phenolic acids contained in coffee. Most negative impacts of serum lipids are driven by select sterols, including kahweol and cafesterol[5], that are present in percolated or boiled coffee but reduced greatly in paper-filtered drip coffee and espresso preparations[6] [7] [8].
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