Is coffee good or bad for your health? Since it first became popular, the health effects of coffee have been debated vigorously. Over the years, numerous studies have produced conflicting results. Nevertheless, on balance, the latest science suggests that moderate coffee consumption appears to have an overall positive effect on human health.

The Health Effects of Coffee and Caffeine On Our Body

The most obvious benefit derived from coffee drinking is increased mental attentiveness due to caffeine. An eight-ounce cup of brewed coffee contains approximately 135 milligrams of caffeine, while instant coffee has about 76 to 106 milligrams. By comparison, cola has 36 to 46 milligrams and the average cup of tea contains about 43 milligrams.

What is Caffeine?

Caffeine is a central nervous system stimulant that promotes the release of adrenaline in the body and suppresses adenosine, a natural relaxant in the brain. This means less fatigue, better mood and increased alertness and energy. If you need to really focus on your work, hold off jet lag, or drive long distances, the stimulating effects of caffeinated coffee will often do the trick. It can also enhance athletic endurance.

However, it is not just the effects of caffeine on the body that make coffee drinking an interesting area of study. Coffee contains amino acids, carbohydrates, minerals, volatile aromatic components and antioxidants.

Several recent studies have shown an inverse relationship between coffee consumption and chronic liver disease and cirrhosis.

Researchers therefore conducted a “meta-analysis,” of published epidemiological studies to look closer at this correlation. In the May 2007 Journal of Gastroenterology, they concluded that coffee drinking appears to lower the risk of liver cancer. According to Drs. Susanna C. Larsson and Alicja Wolk, from the Karolinska Institute in Stockholm, “Data on potential beneficial effects of coffee on liver function and liver diseases have accrued over the last two decades. A protective effect of coffee consumption on liver cancer is biologically plausible.”

The large amounts of antioxidants contained in coffee stave off oxidative stress and inhibit the formation of carcinogens. Experimental animal studies have also specifically shown that coffee has an inhibitory effect on liver cancer.

There’s more good news. In the August 2006 issue of the European Journal of Clinical Nutrition, investigators report that coffee seems to protect against age-related cognitive decline. They concluded that the subjects who consumed coffee had significantly less cognitive impairment than those who did not, with three cups per day providing maximum protection.

Other positive health effects of coffee consumption include protection against, or amelioration of, serious diseases such as Alzheimer’s, Parkinson’s, diabetes, gallstones, asthma, allergies, migraines and the risk of suicide amongst women.

Effects of Caffeine on the Body

However, before you put on another pot of delicious java, be aware of some of the negative effects of caffeine.

The side effects of caffeine begin with the fact that it is habit forming and this can cause problems. Those who are accustomed to getting their fix and then suddenly stop, can suffer from brief caffeine withdrawal symptoms such as headaches, nausea and mood swings. The “coffee jitters” is a nervous condition that can cause anxiety and irritability. For some people it is symptomatic of withdrawal, and for others it may occur through excessive consumption.

Too much caffeine can prevent your body from properly absorbing vitamins and minerals and can also increase the excretion of vitamins and minerals, thus reducing the full benefits of healthy foods.

Caffeine overstimulates the central nervous system, increasing your heart rate and blood pressure. Following the initial energy surge, your body’s energy levels fall due to the lowering of blood sugar.

Caffeine has been shown to have a small effect on intestinal calcium absorption but this should not be a problem as long you ingest the recommended daily calcium allowance.

Caffeine effects can also include stomach irritation.

Excessive caffeine intake—a caffeine overdose–can cause insomnia, sleep disturbances, restlessness, nausea, headache, tense muscles, irregular heart rate, as well as symptoms similar to that of a panic attack. If you feel you may be drinking too much coffee, listen to your body. Then slowly cut down.

Whatever you do, don’t feel guilty about one of life’s simple pleasures…like all things in life, moderation is the key!