Response:

Coffee contains caffeine, a stimulant that impacts the central nervous system and endocrine system, which can temporarily increase blood pressure. Within 30 to 120 minutes of consumption, caffeine activates the sympathetic nervous system, causing a slight increase in heart rate and vasoconstriction. This can lead to an average increase of about 1.9 mmHg in systolic blood pressure and 1.6 mmHg in diastolic blood pressure in adults. For some sensitive individuals, the increase can reach 5 to 10 mmHg. This effect depends on factors such as age, gender, body mass index (BMI), and coffee consumption habits, often being more pronounced in individuals who consume it infrequently or are not accustomed to caffeine.

On average, one cup of coffee contains about 60 to 150 mg of caffeine. Strong filter coffee, espresso, or coffee brewed with more grounds and less water typically contain more caffeine than instant coffee. Consuming approximately 400 mg of caffeine daily (equivalent to four to five cups of coffee, depending on type and strength) can significantly raise blood pressure, especially in those with pre-existing conditions. In contrast, moderate coffee consumption (under 400 mg) does not increase the risk of cardiovascular disease for most adults.

If your blood pressure is stably controlled, you can continue to drink one cup of coffee in the morning. However, individual reactions to caffeine vary. Therefore, you should monitor your body to adjust consumption as appropriate.

Individuals with stable blood pressure can consume coffee in moderation. Photo: Ly Nguyen

You should measure your blood pressure before drinking coffee and check it again after one to two hours. If your blood pressure consistently rises by 10 mmHg or more above your usual level, you should reduce your intake or consult your doctor. If symptoms such as frequent palpitations, abnormally rapid heartbeat, difficult-to-control blood pressure, or prolonged insomnia occur, you should stop consumption and seek specialist medical attention.

Coffee should not be consumed on an empty stomach or when blood pressure is already high. Patients should also limit coffee that is too strong, or with excessive sugar, condensed milk, or fatty cream. The amount of sugar and saturated fats can adversely affect metabolism and cardiovascular health. Additionally, drinking coffee in the evening can cause insomnia, making blood pressure harder to control.

Caffeine also indirectly affects treatment efficacy by altering heart rate and blood pressure. Individuals taking blood pressure medication should maintain regular medication times and avoid sudden changes in coffee habits without professional medical advice.

Controlling hypertension does not solely depend on coffee consumption. Patients need to maintain a low-salt diet (under 5 g of salt daily, as recommended by the World Health Organization), increase vegetable and fruit intake, limit processed foods, maintain a healthy weight, engage in regular physical activity, and have periodic check-ups.

Dr. Nguyen Thi Tuyet, MSc.

Cardiology Department

Tam Anh General Hospital Hanoi