Recent research linked two to three cups of coffee per day with reduced disease risks and longer life. The authors reviewed 85 previous studies from Europe, Americas and Australia that reported coffee consumption and health outcomes; controlling for factors like diet, smoking and alcohol use to isolate its impact alone. They discovered moderate coffee drinking was linked with lower risks of cardiovascular disease, certain cancers, depression, Parkinson’s disease and frailty – likely because caffeine compounds present such as chlorogenic acids help drive these benefits.

This research builds upon prior work that demonstrated an inverse association between happiness and optimism, with higher coffee intake shown to lead to improvements. The current research study sought to measure the strength and effect size of this relationship by comparing baseline measures of psychological well-being (happiness and optimism) with repeated measurements of self-reported coffee consumption across several years. Studies conducted by researchers also took into account other variables related to happiness and optimism when conducting their analyses, with results showing that women who regularly drank coffee reported better well-being over time and greater optimism for the future compared to non-coffee drinkers; they were also less likely to be diagnosed with depression – suggesting its benefits go beyond being just chemical stimulant.

Researchers found that the benefits of drinking coffee increased with more frequent consumption, reaching its peak at four or five small cups per day of regular brew. This quantity maximizes its benefits while simultaneously minimising potential side effects like anxiety, restlessness, insomnia and high blood pressure.

Although it remains unknown exactly why coffee has such beneficial effects, the authors point out that it may help reduce oxidative stress and improve metabolism and energy levels. They suspect these benefits are more closely associated with caffeine than any of its other compounds – suggesting this might help stabilize blood sugar and decrease inflammation; although additional research will need to be conducted into its exact mechanisms of action.

Although these studies involved thousands of participants, they were observational in nature and cannot provide evidence that coffee directly caused disease reduction or mortality reduction. What they can show, however, is that coffee drinking reduces disease risks: for instance a cup a day has been linked with reduced risks of type 2 diabetes and liver cirrhosis as well as decreased chances of suicide and depression/Parkinson’s.

People looking to drink more coffee should steer clear of excess amounts of sugar and cream as this will undermine any possible health benefits. Furthermore, pregnant women must limit their coffee intake as it may cross the placenta into the fetus, potentially leading to miscarriage and low birth weight in future pregnancies. According to The Mayo Clinic guidelines for pregnant or trying-to-get pregnant women who wish to consume 200 milligrams (two eight-ounce cups) daily of caffeine consumption as advised.