Worried about the level of your caffeine intake? Well, new research has indicated that 3-4 cups per day may be doing more good than harm, except during pregnancy
UK researchers seeking to evaluate the evidence for associations between coffee consumption and multiple health outcomes reviewed 201 observational studies, and found that consumption “seems generally safe within usual levels of intake”.
Summary estimates indicated the largest risk reduction for various health outcomes was with an intake of three to four cups per day, and this level of consumption was more likely to benefit health than harm.
Intake of three to four cups a day when compared to no coffee consumption was associated with a 17% reduced risk of all cause mortality, a 19% reduction in risk of cardiovascular mortality and a 15% lower risk of cardiovascular disease.
High versus low coffee consumption was also associated with an 18% lower risk of incident cancer, the researchers found.
Consumption was also associated with a lower risk of several specific cancers and neurological, metabolic, and liver conditions, they said.
Harmful associations were largely nullified by adequate adjustment for smoking, except in pregnancy, where high versus low/no consumption was associated with low birth weight (31% increased risk), preterm birth in the first and second trimester, and pregnancy loss.
Beneficial associations between coffee consumption and liver outcomes (fibrosis, cirrhosis, chronic liver disease, and liver cancer) have relatively large and consistent effect sizes compared with other outcomes, the authors said.
“Consumption is also beneficially associated with a range of other health outcomes and importantly does not seem to have definitive harmful associations with any outcomes outside of pregnancy,” they concluded.
“The association between consumption and risk of fracture in women remains uncertain but warrants further investigation”.
The authors did add that existing evidence was observational and of lower quality, and randomised controlled trials are needed into the effects of caffeine consumption.
The study was published in the BMJ recently