To support this argument, consider this. A recent in-depth research done in Turkey last year revealed an inverse relationship between consumption of coffee and blood levels of all liver enzymes. Conventionally, increased levels of liver enzymes reflect damage and inflammation to the liver. Simply, the more coffee drank, the lesser their enzyme levels.
“Absolutely not,” says Donald Hensrud, medical director of Mayo Clinic's Healthy Living Program. “You have to enjoy life, and if you enjoy tea, keep on enjoying it. It’s all good. There are health benefits to coffee, to black tea and to green tea.” But there can also be problems associated with higher doses of caffeine, he notes. The amount in more than two cups of coffee a day, for example, can interfere with conception and increase the risk of miscarriage. And, he says, because individuals metabolize caffeine at different rates, slow metabolizers may be more susceptible to side effects such as heartburn, insomnia, heart palpitations and irritability.
We’ve been conditioned to believe that caffeine is dehydrating, one of the primary reasons why fitness experts recommend nixing coffee pre- and post-workout. However, recent research suggests that moderate caffeine consumption — up to about 500 mg, or about five cups per day — doesn’t dehydrate exercisers enough to interfere with their workout. In addition, coffee helps battle fatigue, enabling you to exercise longer.
In the Hungry For Change Book we discuss the addictive nature of caffeine and when consumed in large quantities, can lead to adrenal fatigue. Coffee is also a diuretic, meaning it purges water from your body. That said, if you want to function at a high level and remain well hydrated, then it would be a better choice to replace coffee with a natural alternative. The list below provides some great tasting substitutes.
Black coffee, including espresso, has less than 10 calories per 8-ounce cup. If you want to cut calories and keep your coffee as healthy as possible, consider ordering a regular brew without any added ingredients. Black coffee can be bitter, but over time your taste buds will adapt to the bold flavor. If you're new to black coffee, here's a helpful beginner's guide to get you through the initial introduction from Manual Coffee Brewing.
A latte or cappucino can be okay as long as you make sure to ask for it unsweetened, and then use your own stevia if you need a light sweet taste. Since almost every coffee shop only has either sugar or artificial sweeteners as options, I always carry packets of stevia on me when I know I might be getting coffee at a coffee shop on a particular day.
Other studies have tried to pinpoint exactly what in caffeine is helping to halt the onset of these diseases. A 2014 study (14) found that caffeine blocks various tau receptors (a protein that contributes to brain cell degeneration). Another study found that caffeinated coffee increased GCSF (15) - a substance greatly decreased in Alzheimer’s patients - levels in the bloodstream.