Americans drink 400 million cups of coffee each day, according to the website GourmetCoffeeZone.com. While some coffee can be perfectly safe, too much can affect your body in a negative way. Excessive coffee drinking is linked to high cholesterol and blood pressure as well as elevated stress hormones.
CHOLESTEROL
A compound found in coffee when brewed a certain way can increase your cholesterol, reports a study published in the journal "Molecular Endocrinology" in 2007. Cafestol is abundant in espresso, French press and Scandinavian brew coffees. These coffees are brewed without a filter, so none of the cafestol compound is removed. Cafestol increases cholesterol by inhibiting an intestinal receptor that regulates your cholesterol levels. However, researchers note that you'd have to drink a lot: five cups of French press coffee can raise cholesterol between 6 and 8 percent over four weeks.
BLOOD PRESSURE
Drinking several cups of coffee per day can raise your blood pressure. Blood pressure is the measurement of the force blood exerts against your vessel walls and is measured by two numbers. The top number, systolic pressure, indicates the amount of force while your heart is pumping. The bottom number, diastolic pressure, is the force your vessels face during the filling phase. The greater the force, the higher your pressure and the higher your risk of heart disease. Drinking an excessive amount of coffee can raise your systolic pressure between 3 and 14 points and diastolic pressure between 4 and 13 points.
STRESS
If you drink several cups of coffee per day, you risk putting your body into a stresslike response, according to a study published by Duke University in 1999. This study tested the effects of morning coffee, compared with no coffee, on regular habitual coffee drinkers. Throughout the day, heart rate, blood pressure and stress hormones were measured in 72 subjects over two weeks. The researchers found that four to five cups of coffee increased the stress hormones adrenalin and noradrenalin by 32 percent and 14 percent, respectively. Blood pressure also increased. These reactions indicate that coffee causes a stress response inside the body, the same as if you were having a stressful day.
SAFETY
Light coffee consumption is safe for most people, states Sheldon G. Sheps, MD of MayoClinic.com --- about 200 mg of caffeine per day: two 12 oz. cups of coffee. These are general guidelines: your condition may alter this recommendation. Speak with your doctor about the safest amount of coffee for you to consume.