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How much caffeine is really in one cup of coffee?

How much caffeine is really in one cup of coffee?

coffee_beansPrevious research has shown that regularly drinking coffee could offer a number of health benefits, including reducing prostate cancer risk, improving symptoms related to Parkinson’s disease, staving off the development of Alzheimer’s, decreasing diabetes risk and providing antioxidants.

But too much caffeine can make you jittery, disrupt your sleep and, potentially, shorten your life span. So it’s often recommended that you drink coffee in moderation, which is defined as two or three eight-ounce cups of brewed or drip coffee.

The problem with recommending a certain number of cups, reports Scientific American, is that new research shows the caffeine and caffeoylquinic acid (CQA) content can vary greatly depending on the type and preparation of the coffee. From the piece:

Results showed that the caffeine-to-CQA ratio in espressos ranged from 0.7–11, depending on the preparation conditions. With serving volumes from 13–104ml, it’s no wonder that Crozier says ‘cup of coffee is an exceedingly variable unit. To estimate health benefits using cups may be very difficult,’ – and inadvisable in epidemiological studies.

But what are CQAs? Beans contain various (poly)phenols, including 3-, 4- and 5-O-caffeoylquinic acids, the main phenolic compounds in coffee. Epidemiological studies have suggested the link between the lower risk of type 2 diabetes, cardiovascular diseases, and endometrial and hepatocellular cancer in habitual coffee consumers might be due to the presence of CQAs in coffee. They sound like super-compounds, but that’s a big ‘might’, and research continues.

Whilst the biological effects of CQAs are uncertain, one thing we do know about them is they are more sensitive to roasting than caffeine. The bean or blend also affects the caffeine-to-CQA ratio. Arabica and Robusta are the most common bean types and the latter contains twice as much caffeine as the former.

The article highlights the need to better inform consumers about the actual amount of caffeine in coffee and the need for more research on the health benefits of coffee.

Previously: How the body’s natural defenses help protect cells from toxins in everyday foods and flavorings, What is coffee?, For new moms, coffee scores a point: Caffeine doesn’t seem to interfere with baby’s sleep in study and Does coffee lower the risk of prostate cancer?
Photo by Nina Matthews

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