Americans love their coffee, especially first thing in the morning. Turns out that early morning tall latte may do more than just perk you up. It also affects the part of your brain which conrols anxiety and stresses you out.

Studies show if you consume your coffee before 1 p.m., you could still be feeling the stress and anxiety effects even into the evening. These stress effects manifest themselves as high blood pressure, high resting heart rate and general nervousness and uneasiness. These can all interfere with sleep.

One study had a group of volunteers drink the amount of caffeine in a normal cup of coffee on one day and a placebo on another. When consuming the caffeine, the participants felt more stressed, had a slightly higher blood pressure and produced over 30% more of a stress hormone called norepinephrine.

It is already established that if you consume a regular cup of coffee in the morning it will take you about four hours to get half the caffeine out of your system. After eight hours you will still have 25% remaining in your blood stream.

Researchers suggest that those people who have stress related conditions, or any type of heart disease reduce the amount of coffee they consume. The wake-up effects of coffee are pleasant but if you get the anxiety jitters, coffee may not be a healthy beverage choice for you.