An estimated 90% of Americans regularly consume caffeine.
Health benefits of caffeine
00:59 - Source: CNN

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Study after study extols the merits of three to five cups of black coffee a day

How you brew coffee also contributes to the health factor

CNN  — 

It’s one of the age-old medical flip-flops: First coffee’s good for you, then it’s not, then it is – you get the picture.

A massive review of the scientific literature on coffee published in the British Medical Journal found that drinking three to fours cups of black coffee a day provides the most health benefits overall. Prior studies have found similar benefits reducing risk for such issues as melanoma, heart disease, multiple sclerosis, type 2 diabetes, liver disease, prostate cancer, Alzheimer’s, computer-related back pain and more.

But the study also found two areas of concern. High levels of coffee consumption (more than four cups) during pregnancy was associated with low birth weight, pre-term birth and stillbirths. For women with a higher likelihood of bone fractures, coffee raised that risk; the same was not true for men.

Prior research also suggests people with