Tea and coffee can wake you up and keep you focused, but don’t over-take caffeine, it may trigger migraine or IBS in sensitive people.
Caffeine is a natural chemical that activates the central nervous system, which means it can improve nerves and thinking processes. Regular consumption of coffee and/or caffeine in tea can increase short-term attention and alertness and long-term memory. Although most people like the “rejuvenating” effect of caffeine, some people are sensitive to caffeine and feel nervous or uncomfortable after taking a certain dose. If you fall into the second category, you need to eliminate caffeinated beverages or adjust your intake to meet your personal affordability. Those with sleep problems or insomnia may need to stop drinking caffeinated beverages (or omit them altogether) eight hours before bedtime.
In addition, caffeinated beverages can sometimes cause migraines in sensitive people. IBS patients should pay attention: some people with IBS will experience symptoms after ingesting caffeinated coffee or tea.
Caffeine may also have some adverse effects on women before they enter the menstrual cycle. Some studies have shown that the effects of caffeine will be amplified before women’s menstrual period. If this is the case for you, switch to herbal tea or decaffeinated beverages at this time in the cycle.