Does caffeine reduce the risk of liver disease and boost memory?
Caffeine, like chocolate, often receives bad publicity. While in some instances, and in excess, these can have negative effects on our body, they can also be quite beneficial.
Of course, some people are more sensitive to the negative effects of caffeine. For example, excess caffeine can create anxiety, nausea (particularly if taken on an empty stomach), an increased heart rate, and even depression in some people.
But scientists have turned up some interesting facts on caffeine. For example, caffeine blocks the effects of a neurotransmitter in the brain (“adenosine”) that otherwise makes us feel tired. This is why it works so well to keep us awake. It also encourages the release of another brain chemical called “dopamine” that contributes to a feeling of well-being.
Two studies found that drinking caffeine-containing drinks like coffee and tea had a protective effect for those at risk of developing liver disease. The results showed that people who drank more than two cups of coffee a day had a 44% lower chance of showing actual liver damage than those who drank no caffeine. This was not a clinical trial, and the reason why coffee and tea had such an effect is unknown. Coffee and tea contain a range of plant chemicals (“phytonutrients”) that could be responsible for this.
A 2005 Norwegian study also found similar benefits for coffee with regards to liver disease. Accordingly to this study, drinking three cups of coffee a day could lower the risk of death from liver cirrhosis.
Even if you're not at risk of liver disease, caffeine still has some advantages. Recent research from Austria showed that caffeine may enhance short-term memory. Researchers found an increase in brain activity in the parts of the brain associated with memory and attention. These parts of the brain were the frontal lobe and the anterior cingulum. An earlier study (2004) found that caffeine did support short-term memory, but only when it was related to a topic that people were already thinking about. This study found that when testing coffee's effects on unrelated subjects, short-term recall was actually inhibited.
Everything does have a flip side, though. Adenosine, which is blocked by coffee, is also calming. This could be why it can also cause anxiety in some individuals. After all, the balance of our brain chemistry is unique, and when we are addicted to stimulants like caffeine, we lose sensitivity to our natural stimulants such as dopamine and adrenaline.
