If you are worrying about hypertension you should understand a fact or two about caffeine and blood pressure. There is still an ongoing discussion as to what exactly happens when you drink coffee, tea or pop, but many of the questions have already been answered.
Caffeine effect on health
Caffeinated beverages have been demonstrated to have a tremendous effect on our health and this effect is not limited to the cardiovascular system. Coffee and tea is actually helpful in the prevention and recovery from certain types of cancers including breast, colon, and prostate. In fact it is the caffeine constituent that can be a very important health ingredient in some instances. Diabetes, Parkinson’s, gout, and asthma also have a specific relationship with coffee and caffeine.
Coffee is not the only caffeinated beverage. Tea and cola are also two more popular beverage types containing caffeine. Interestingly there is a difference between caffeine and blood pressure for these three types of beverages.
Coffee, caffeine and blood pressure
Coffee’s effect on the circulation has been well researched. By now it is clear that people with hypertension react differently to caffeinated beverages than people with normal blood pressure and that younger people are affected more than older individuals.
Cardiovascular effect of caffeine in coffee can be divided into two different ways: immediate effect, which reflects cardiovascular effect 30-60 min after ingestion and long term which relates to drinking coffee regularly over many months or years. These two are very different.
- Immediate effects are unequivocal: caffeinated coffee raises blood pressure. However, pre- or already hypertensive individuals reacts to caffeine with the strongest spike[i]. The caffeine spike in people with optimal or normal heart function seems to be much lower and also shorter-lasting.
- Long-term effects of caffeinated coffee on blood pressure are more obscure. Although this topic was addressed by many studies there is still no consensus on caffeine and blood pressure. Out of 18 systematic studies five found no correlation between the two, six studies found positive correlation, and seven found inverse correlation between coffee drinking habits and hypertension[ii]. As of today we are still not sure if long-term coffee consumption causes hypertension, but we can surely conclude that people with already compromised cardiovascular system should be cautious with excessive coffee drinking habit.
Caffeine in tea also changes blood pressure
A study done on green and black tea drinkers have shown that tea, despite a common myth of safety, is capable of producing a substantial spike of blood pressure within 30 minutes. A study done on 20 healthy males showed that both black as well as green tea cause the spikes and black tea usually higher than green tea[iii]. Despite this immediate blood pressure spike tea, whether green or black, does not seem to produce a long term blood pressure effect, unlike some studies suggest happens with coffee.
Caffeine in pop has a substantial effect on blood pressure
Caffeine and blood pressure effects of pop apparently depends whether soda is sweetened with sugar or artificial sweetener. A 10-week experiment brought surprising discoveries. Participants who drank sugar-sweetened pop saw an increase in both systolic and diastolic numbers. In contrast, those who consumed artificially sweetened soda had lower numbers at the end of the study[iv].
Sorry to say, but artificially-sweetened soda, will not be prescribed for hypertension as of yet despite this study. Pop drinking habit has been proposed as a marker for poor nutrition, so do not expect pop to suddenly appear next to Hawthorn berries and aged garlic in a health food store isles.
However this study has shed some light on other dietary variables that modify caffeine effect: sugar and artificial sweeteners. Maybe the relationship between caffeine and blood pressure needs to be examined more thoroughly taking into consideration the type and amount of sweetener.
So should you drop or continue drinking caffeinated beverages if you are worried about heart? From the blood pressure point of view if you have no risk for hypertension either caffeinated coffee or tea should be fine. If you already have high blood pressure or white coat syndrome stick to tea unless you are looking to benefit from other properties of coffee. As to pop and soda, due to their lack of any kind of health benefits, you most certainly will be better off not using them regardless whether it is caffeine-free, sugar-free, or even calorie-free.
Discovering the complete story behind the relationship between caffeine and blood pressure will take some time yet. Until then you will benefit from learning what other things, besides caffeine, can make your blood pressure go up and down. You should also be aware when low blood pressure numbers are way too low .