How much coffee is too much?
Advice from our GP on coffee and how much caffeine might be too much:
Coffee is a popular “pick me up” drink largely due to the metabolic effects of caffeine — the drug it contains. Caffeine is absorbed quickly into the body and passes to the brain where it acts as a stimulant exciting the brain and nervous system. It also acts as a diuretic increasing the loss of water through the kidneys.
Caffeine has a number of effects in the body. It increases heart rate and alertness. This can lead to a feeling of anxiety or jitters, racing heart, difficulty sleeping, headaches, dehydration or dizziness. If you are used to ingesting caffeine and you stop it suddenly you may experience withdrawal symptoms such as drowsiness, headaches, irritability, nausea and vomiting. Ingestion of large amounts of caffeine may reduce calcium absorption increasing the risk of osteoporosis.
A caffeine intake of over 500mg daily is considered high and may have detrimental health effects. A single shot of espresso has 40 to 75 mg of caffeine. Remember that a large shop bought coffee may have 3 or more of these.
There are some health benefits to coffee consumption. It does contain antioxidants and consuming less than 400mg daily has been associated with reduced risk of cardiovascular disease along with a possibly reduced risk of liver and prostate cancer. However it was suggested that consumption of coffee might increase the risk of urinary tract cancers.
The World Health Organisation has expressed concern about the effects of high caffeine intake on health. Caffeine provides no health benefits and is not necessary in a normal diet. It seems like for coffee, moderation is key.