It is generally understood that coffee, tea and soft drinks will elevate your blood pressure, and that elevated pressure could lead to a heart attack or a stroke. Caffeine is the most widely used drug in the world. It has been known to produce undesirable side effects such as nervousness, insomnia, irregular heart beat, high blood sugar and cholesterol levels, excess stomach acids and heartburn. Caffeine stimulates the central nervous system and can cause mild alertness, heightened anxiety and body tension. It can be habit forming.

It depends on how you take it and how much you take. Age and size have a lot to do with it. A caffeinated soft drink consumed by a small child can have the same effect as four cups of coffee consumed by an adult. It can produce trembling, nervousness, chronic muscle tension, irritability, throbbing headaches, disorientation, depression and insomnia. Use of caffeine combined with smoking can be a double threat. Nicotine also raises blood pressure.

The use of caffeine and nicotine can be harmful to your health. Here is an experiment that you can conduct to see for yourself. It could be a great science fair project, or you might do it just for your own edification. You should recruit a number of subjects of different age and gender. The more the merrier. Twenty subjects more or less; it's up to you.

You will need lots of soda, either Coke or Mountain Dew, or Pepsi, or any soft drink with caffeine. You will need coffee, lots of it. Make sure you do not use decaffeinated coffee. You will require a timer.

An easy-to-use blood pressure monitor is required. You must learn how to use it properly. If you are testing children under age 21, you should get their parents' permission in writing.

You should get assistance in the proper use of a blood pressure monitor. It is not difficult to get proper readings once you learn the technique. Test half of the subjects with soft drinks like Coke or Mountain Dew.

Each contains about 80 mg of caffeine. Test the other half with coffee. Each cup contains about 80 to 160 mg of caffeine.

You must first test the subject's blood pressure before consuming any of the drinks. Keep careful charts, make precise notes. Check each subject's blood pressure again, after they have consumed the caffeinated drinks, thirty minutes later, and again 60 minutes later. Blood pressure readings can often vary from reading to reading. What have you learned? Did the blood pressure readings go up?.

Mort Barish is co-founder of Terimore Institute, Inc. Terimore provides hundreds of science fair projects with step-by-step guides for children in grades K-12 to help them successfully compete in science fairs. Find fun, easy and award-winning science fair projects at www.terimore.com!