Much debate and consideration has gone into the role of caffeine in raising BP. To this day the medical community has not come to a solid agreement on the overall effects of caffeine on BP. However, one thing that is for certain is that caffeine is known to cause spikes in BP. How long these spikes is yet another contested area. Researchers have noted that consumption of coffee appears to be positively linked to an increased risk of stroke (thromboembolic) in men who are middle aged and who have hypertension.
Some doctors have noted that the development of tolerance during continued use of caffeine may explain why coffee consumption in some epidemiological studies did not appear to have a clear effect on BP. There is a large cross-sectional study carried out involving 5,000 participants. The study showed that caffeine consumption within the past three hours was linked to significantly higher BP readings than when caffeine was not consumed in the last nine hours. Another study involving over 330 women supported this larger study by showing elevated BP following recent caffeine consumption
Studies on the effects of caffeine on BP agree on yet another point. It is clear that BP elevation associated with caffeine take is not at all affected by the race or sex of a person. People who are considered to be habitual caffeine users when reduced from caffeine offered lower BP readings. These habitual consumers would otherwise show rise in BP due to caffeine inquiry confirming that acute intake of coffee has been shown to result in higher BP readings. Coffee contains caffeine. The caffeine component in coffee is responsible for the high BP effect. Several studies have shown that regular coffee intake exceeded BP whereas decaffeinated coffee had no effect.
A single dose of caffeine equivalent to two to three cups of coffee increases systolic BP by up to plus or minus 14mmHg and diastolic pressure by up to plus or minus 13mmHg in normotensive subjects. When a person consumes caffeine, BP typically elevates within 30 minutes and the maximal increase occurs 60 to 120 minutes. This increase in BP may last for over 2 to 4 hours. Interestingly some study findings suggest that the pressure effect of caffeine is stronger in older people than observed in the youngger ones.
The debate on caffeine role in BP elevation is set to continue until a comprehensive study is done. In the meanime the best approach is to treat caffeine as having a negative influence on hypertension.