The Health Benefits of Coffee: What Science Tells Us

For millions of people, coffee is an essential part of the day: a moment of calm in the morning, a source of energy before work or a reason to sit down and connect with someone.

Coffee is also much more than caffeine. It contains hundreds of naturally occurring compounds, including chlorogenic acids and other polyphenols. These antioxidant-active compounds are an important part of coffee’s chemistry.[1] Their potential effects have been investigated extensively in peer-reviewed scientific research.[2]

The results are encouraging. Regular, moderate coffee consumption has been associated with several positive health outcomes, from metabolic and liver health to alertness and physical performance.

Coffee Is More Than Caffeine

Caffeine is responsible for many of coffee’s immediate effects, but other compounds may help explain its longer-term associations with health.

Green coffee beans contain chlorogenic acids, a family of polyphenols that contribute to the bean’s natural flavour, acidity and chemical character. Coffee also contains trigonelline and many other plant compounds. During roasting, some of these compounds are reduced or transformed, while new ones—including antioxidant-active melanoidins—are created.[2]

For many regular coffee drinkers, coffee is one of the most important sources of dietary polyphenols. Researchers are studying how these compounds may interact with processes related to oxidative stress, inflammation, glucose metabolism and cardiovascular health.

No single compound tells the whole story. Coffee is a complex beverage, and its potential benefits are likely to result from the interaction of many components rather than from caffeine or chlorogenic acids alone.

The Bigger Picture

Some of the strongest evidence comes from large studies that have followed coffee drinkers over many years.

An umbrella review published in The BMJ examined more than 200 meta-analyses covering a wide range of health outcomes. Coffee consumption was more often associated with benefit than harm, with the largest overall reductions in risk commonly observed at around three to four cups per day.[3]

Research involving three large prospective cohorts also found that people who consumed moderate amounts of coffee had lower rates of total mortality than non-drinkers. Similar associations were observed for caffeinated and decaffeinated coffee.[4]

Most long-term coffee research is observational. It can identify consistent relationships but cannot prove that coffee alone caused a particular outcome. Nevertheless, the size and consistency of the research provide reassurance that moderate coffee consumption can form part of a healthy lifestyle for most adults.

Coffee and Type 2 Diabetes

One of the most consistent areas of coffee research concerns type 2 diabetes.

A systematic review and dose-response meta-analysis found that consumption of both caffeinated and decaffeinated coffee was associated with a lower risk of developing type 2 diabetes.[5] The fact that the association appears with decaffeinated coffee suggests that compounds other than caffeine may be involved.

Chlorogenic acids and other coffee compounds are being studied for their possible roles in glucose metabolism, insulin sensitivity and inflammation. Research into these mechanisms is continuing, and coffee is not a treatment for diabetes. However, the long-term association between regular coffee consumption and a lower risk of developing type 2 diabetes is one of the most consistently observed findings in coffee research.

What is added to the cup also matters. Large quantities of sugar, flavoured syrups or sweetened cream can completely change its nutritional profile. A naturally balanced and flavourful coffee is easier to enjoy without covering it with unnecessary sweetness.

Coffee and Liver Health

The evidence relating coffee to liver health is particularly noteworthy.

The BMJ umbrella review found that coffee consumption was associated with lower risks of several liver conditions.[3] A separate systematic review and dose-response meta-analysis found that both caffeinated and decaffeinated coffee were associated with a lower risk of hepatocellular carcinoma, the most common form of primary liver cancer.[6]  Coffee consumption has also been associated with lower risks of chronic liver disease and cirrhosis. Researchers are investigating several possible explanations, including the combined effects of chlorogenic acids, caffeine and other coffee compounds. 

These findings do not replace medical care, but they make liver health one of the most compelling areas in the wider body of coffee research.

Alertness and Concentration

Coffee’s immediate effects are among the easiest to recognise—and the best established scientifically.

A major review of caffeine research found that low to moderate doses can improve alertness, vigilance, attention and reaction time.[7] This helps explain why coffee is so closely connected with the beginning of the working day and with moments that demand sustained focus. The response is individual. The amount that improves concentration for one person may make another feel restless. The aim is not to consume as much caffeine as possible, but to find the amount that feels comfortable and useful.

A carefully brewed cup can provide that lift while also offering something an energy drink cannot: aroma, flavour, origin and the simple pleasure of the ritual itself.

Coffee and Physical Performance

Caffeine can also support several aspects of physical performance.

The International Society of Sports Nutrition concluded that caffeine can improve endurance, muscular endurance, movement velocity and performance in a variety of sports and exercise activities.[8]  Benefits have been observed at moderate doses, and larger amounts do not necessarily produce better results. Timing, body size, regular caffeine use and individual sensitivity can all influence the response.

Coffee can therefore be an enjoyable pre-exercise ritual for people who tolerate caffeine well—without the need for highly sweetened energy drinks or complicated supplements.

Coffee and Cardiovascular Health

Caffeine can temporarily increase blood pressure, especially in someone who does not consume it regularly. However, that short-term response is different from the effects associated with habitual coffee drinking.

Large observational reviews have generally found that moderate coffee consumption is not associated with a higher risk of cardiovascular disease. Several analyses have instead reported associations with lower risks of cardiovascular disease and cardiovascular mortality.[2,3]

Brewing method is relevant. Unfiltered methods allow more cafestol and kahweol into the cup. Consuming large quantities of unfiltered coffee can increase LDL cholesterol in some people. Paper filters retain much of these compounds, making filtered coffee a sensible choice for anyone who needs to manage cholesterol.[2]

Why Our Medium Roast Matters

Roasting transforms almost every aspect of coffee: aroma, sweetness, acidity, body, colour and chemical composition.

As coffee is roasted, heat gradually reduces its chlorogenic-acid content. Research has found that these losses become greater as roasting progresses towards darker levels.[9] At the same time, roasting creates melanoidins and other compounds that contribute flavour, colour and antioxidant activity.[10]

At Copala, we choose a medium roast because it develops the sweetness, aroma and body we want while preserving more of the coffee’s original character than a very dark roast. A medium profile also generally retains more chlorogenic acids than darker roasting, while still developing the rich flavours created through heat.

It is a decision guided first by flavour, but it fits naturally with what the science tells us about roast development.

From Our Estate to Your Cup

The quality of coffee begins long before roasting.  Copala coffee comes from our family estate in Zambia’s Copperbelt. After harvesting, we dry our coffee slowly on raised trays in the shade. This allows us to manage heat and moisture loss carefully while preserving the character developed in the fruit and seed.

We then medium roast the coffee to express its natural sweetness, balance and origin without allowing excessive roast flavour to dominate the bean.

This careful approach—from growing and harvesting to drying and roasting—creates a coffee that is naturally expressive and enjoyable without needing to be hidden beneath sugar or flavoured syrups.

For us, good coffee is not only about what it contains. It is also about knowing where it came from, how it was handled and why each production decision was made.

How Much Coffee Is Sensible?

There is no ideal number of cups for everyone. Cup sizes, brewing methods and caffeine concentrations vary considerably.  The European Food Safety Authority concludes that total caffeine intake of up to 400 milligrams per day generally does not raise safety concerns for healthy, non-pregnant adults. During pregnancy and breastfeeding, it recommends limiting caffeine consumption to no more than 200 milligrams per day.[11]

These figures are safety limits, not daily targets. Many people feel better with less.  Caffeine can affect sleep and may cause restlessness, anxiety, digestive discomfort or palpitations in sensitive individuals. Anyone with a medical condition, taking medication or pregnant should follow the advice of their healthcare professional.

Decaffeinated coffee remains an excellent choice for anyone who wants to enjoy the flavour, polyphenols and ritual of coffee with considerably less caffeine.

A Better Daily Ritual

The scientific picture surrounding coffee is increasingly positive.

Moderate coffee consumption has been associated with lower risks of type 2 diabetes, several liver conditions, cardiovascular disease and premature death. Caffeine can reliably support alertness, attention and aspects of physical performance.

But the value of coffee is not found in health statistics alone. A good cup gives us a reason to pause. It can bring clarity to a busy morning, energy to a demanding afternoon and pleasure to an ordinary daily moment.

At Copala, we believe that ritual should begin with coffee grown with traceability, dried with patience and roasted with intention. Our medium roast is designed to preserve the bean’s character while developing the sweetness, balance and aroma that make each cup worth returning to.

That is coffee at its best: carefully made, deeply enjoyable and naturally at home in a healthy life.

References

1. Arnot, B. The Coffee Lover’s Bible: Change Your Coffee, Change Your Life. William Morrow Paperbacks, 2018, particularly pp. 18–19, 54–59 and 361–365. Book record and ISBN

2. van Dam, R. M., Hu, F. B. & Willett, W. C. “Coffee, Caffeine, and Health.” New England Journal of Medicine 383, 369–378 (2020). https://doi.org/10.1056/NEJMra1816604

3. Poole, R. et al. “Coffee consumption and health: umbrella review of meta-analyses of multiple health outcomes.” The BMJ 359, j5024 (2017). https://doi.org/10.1136/bmj.j5024

4. Ding, M. et al. “Association of Coffee Consumption With Total and Cause-Specific Mortality in 3 Large Prospective Cohorts.” Circulation 132, 2305–2315 (2015). https://doi.org/10.1161/CIRCULATIONAHA.115.017341

5. Carlström, M. & Larsson, S. C. “Coffee consumption and reduced risk of developing type 2 diabetes: a systematic review with meta-analysis.” Nutrition Reviews 76, 395–417 (2018). https://doi.org/10.1093/nutrit/nuy014

6. Kennedy, O. J. et al. “Coffee, including caffeinated and decaffeinated coffee, and the risk of hepatocellular carcinoma: a systematic review and dose-response meta-analysis.” BMJ Open 7, e013739 (2017). https://doi.org/10.1136/bmjopen-2016-013739

7. McLellan, T. M., Caldwell, J. A. & Lieberman, H. R. “A review of caffeine’s effects on cognitive, physical and occupational performance.” Neuroscience & Biobehavioral Reviews 71, 294–312 (2016). https://doi.org/10.1016/j.neubiorev.2016.09.001

8. Guest, N. S. et al. “International Society of Sports Nutrition position stand: caffeine and exercise performance.” Journal of the International Society of Sports Nutrition 18, 1 (2021). https://doi.org/10.1186/s12970-020-00383-4

9. Moon, J.-K., Yoo, H. S. & Shibamoto, T. “Role of Roasting Conditions in the Level of Chlorogenic Acid Content in Coffee Beans: Correlation with Coffee Acidity.” Journal of Agricultural and Food Chemistry 57, 5365–5369 (2009). https://doi.org/10.1021/jf900012b

10. Smrke, S. et al. “How does roasting affect the antioxidants of a coffee brew?” Food & Function 4, 1082–1092 (2013). https://doi.org/10.1039/C3FO30377B

11. EFSA Panel on Dietetic Products, Nutrition and Allergies. “Scientific Opinion on the Safety of Caffeine.” EFSA Journal 13, 4102 (2015). https://doi.org/10.2903/j.efsa.2015.4102

This article provides general information and is not a substitute for individual medical advice.