Coffee has been flowing through human societies for more than six centuries. Today, average consumption sits at close to two kilograms per person each year, with tastes shaped not only by culture but also by genetics that influence how people metabolise caffeine and experience its effects.
While coffee can cause a temporary rise in blood pressure, health experts say most people – including many with hypertension – do not need to give it up. The key message is moderation and awareness of individual risk.
Blood pressure refers to the force exerted by circulating blood on artery walls. It is measured using two figures: systolic pressure, the top number, which reflects pressure when the heart contracts; and diastolic pressure, the lower number, recorded when the heart relaxes between beats.
A reading below 120/80 millimetres of mercury (mm Hg) is considered normal. Consistent measurements of 140/90 mm Hg or higher indicate hypertension.
High blood pressure is often described as a silent condition because it typically produces no symptoms. Left untreated or poorly managed, it raises the likelihood of heart attack, stroke and worsening heart or kidney disease. Around 31% of adults are estimated to have hypertension, and roughly half do not know it. Even among those taking medication, close to half do not achieve adequate control.
Caffeine acts as a stimulant. In some people it increases heart rate and may contribute to irregular heart rhythms. It also triggers the release of adrenaline from the adrenal glands. This response makes the heart beat more forcefully and narrows blood vessels, which can lead to a rise in blood pressure.
Caffeine levels in the bloodstream usually peak between 30 minutes and two hours after drinking coffee. Its half-life – the time taken for levels to fall by half – ranges from three to six hours. That variation depends on factors including age, genetic differences in metabolism and whether someone drinks coffee regularly. Habitual drinkers tend to process caffeine more quickly.
Reviews of research have found that caffeine consumption can lift systolic blood pressure by between 3 and 15 mm Hg and diastolic pressure by 4 to 13 mm Hg. The size of the effect differs between individuals and may be more concerning for people who already have hypertension or heart or liver disease. In those cases, doctors recommend discussing caffeine intake with a healthcare professional.
Coffee actually contains hundreds of phytochemicals – naturally occurring compounds that affect flavour and may influence health.
Some of these appear to interact with blood pressure regulation. Melanoidins, produced during the roasting process, may play a role in fluid balance and enzyme systems linked to blood pressure control. Quinic acid has been associated with improvements in the function of blood vessel linings, which may help them better accommodate changes in pressure and potentially reduce both systolic and diastolic readings.
Large population studies suggest that drinking coffee does not, in itself, raise the long-term risk of developing hypertension.
A review of 13 studies involving a combined 315,000 participants found no overall link between coffee intake and the development of high blood pressure. During follow-up, 64,650 people were diagnosed with hypertension, yet researchers concluded that coffee consumption was not associated with increased risk.
The findings were consistent across men and women, varying amounts of coffee, caffeinated and decaffeinated types, smoking status and length of follow-up. Some US-based and lower-quality studies suggested a possible lower risk among coffee drinkers, though those results were considered less reliable.
However, evidence is more mixed for people with very high blood pressure. A Japanese study tracking more than 18,000 adults aged 40 to 79 over nearly 19 years found that among participants with grade 2–3 hypertension – defined as systolic pressure of at least 160 mm Hg or diastolic pressure of at least 100 mm Hg – those drinking two or more cups of coffee daily had double the risk of dying from cardiovascular disease compared with non-drinkers.
The same study found no increased cardiovascular risk among people with normal blood pressure or mild (grade 1) hypertension.
For most adults, there is no blanket recommendation to eliminate coffee. Instead, experts advise:
People with systolic blood pressure of 160 mm Hg or higher, or diastolic pressure of 100 mm Hg or higher, may wish to restrict intake to one cup a day and consult their doctor.
For most coffee drinkers, the evidence suggests that a moderate habit can fit within a heart-conscious lifestyle, provided it is balanced with broader efforts to manage blood pressure.
IMPORTANT LEGAL INFO This article is of a general nature and FYI only, because it doesn’t take into account your personal health requirements or existing medical conditions. That means it’s not personalised health advice and shouldn’t be relied upon as if it is. Before making a health-related decision, you should work out if the info is appropriate for your situation and get professional medical advice.
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