Coffee and caffeine

Question 1

What is the caffeine molecule?

Answer 1

1,3,7-trimethylxanthine

Question 2

What is the mean half-life of caffeine in the human body?

Answer 2

6 hrs. according to Hammami et al., 2010, Trials , and also Statland & Demas, 1980, Am J. Clin. Pathol. Some others apparently peg it at 5hrs. Wikipedia’s entry for caffeine lists 5 hrs.

Question 3

When does peak plasma concentration occur after consumption?

Answer 3

My reading of the results of Hammami et al., 2010, is that it’s approx. 2.5 hrs.

Question 4

What are some of the properties of caffeine?

Answer 4

1. vasoconstrictor 2. diuretic

Question 5

What are some negative physical effects of caffeine?

Answer 5

• decreased fine motor control • increased blood pressure • increased urine removal

Question 6

Is drinking coffee associated with stroke?

Answer 6

A meta-analysis by Larsson and Orsini (2011) found “moderate coffee consumption may be weakly inversely associated with risk of stroke”. Another meta-analysis by Kim et al. (2012) also found an inverse relationship – drinking coffee decreases risk of stroke.

Question 7

Is drinking coffee associated with an increased risk of cancer?

Answer 7

Meta-analyses concluded that coffee consumption may actually be associated with a lower risk of liver cancer, lower risk of prostate cancer, and lower risk of breast cancer.

Question 8

Can coffee damage your liver?

Answer 8

“Drinking coffee is associated with better laboratory values in those at risk for liver disease. In patients who already have liver disease, it’s associated with a decreased progression to cirrhosis. In patients who already have cirrhosis, it’s associated with a lower risk of death and a lower risk of developing liver cancer. It’s associated with improved responses to antiviral therapy in patients with hepatitis C and better outcomes in patients with nonalcoholic fatty liver disease.” The authors of the review argue daily coffee should be encouraged in subjects with chronic liver disease.