The Half Life of Caffeine
Caffeine has become the hot-topic of the moment. With caffeine levels continuing to climb – many people are asking – what exactly is the limit?
The Mirror asks this and recommends a safe amount of 400-500 milligrams of caffeine per day. This is of course affected by body weight, health, and individual sensitivity.
“I typically have four cups [of coffee] a day. Sometimes it’s more,” says Drury freshman Cody Carr. This would put Carr well past the safe amount per day. It is this excessive use of caffeine (over 500 mg per day) that has been shown, by the Mayo Clinic, to cause nervousness, insomnia and headaches.
Caffeine takes a certain amount of time to work through your system. One study some years ago showed that the half-life of caffeine in healthy adults is 5.7 hours (see source). This means if you consume 200mg of caffeine at mid-day, you would still have 100mg in you at around 5.45pm.
The same study showed that people with compromised liver function had a significantly longer half-life (a 49-year-old woman having alcoholic hepatic disease had a serum half-life of 168 hours).
The death by caffeine calculator is for entertainment purposes – but does highlight excessive doses of caffeine can lead to health issues – and if your liver is not the healthiest specimen – then even more care is needed!
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To be addicted to anything so as to make big companies rich seems like a no-brainer to be taboo for any of you… To make a product that is addicting for the purpose of addicting people to it so that you can sell to the addicts after you addict them seems like it should be ILLEGAL….. If you have to make a law so a dork puts a helmet on his head before he rids a bike, it shouldn’t be to big of a stretch to make it illegal to make children addicted to your product that is going to make you rich… Some people will do anything for a buck… You parents that allow your children to become addicted to this sh– should be —- I am not going to say what I am thinking….
This might be a wake up call for some but companies are like mobs; they make money, they get political backing (and protection), they make more money. If you think you live in a free country then just try driving without your seat belt. Legislators are NOT acting in our (we the people) best interest, if they were then cigarettes would be as legal as cocaine. Seat belts are a great idea, but it makes for a very bad law. You will still be able to get a triple shot espresso at you favorite java vendor, you can smoke until your lungs dissolve… it’s legal. If I drive without my seatbelt I will be fined the equivalent of my weeks grocery budget… but I can still get a coupon for cheap or free cigarettes. It is all because given the opportunity, people will take advantage of people (most of the time). Welcome to the real world.
i dont think the coffee companies are making that much money. iv never heard of a millionare ceo of a coffee company… and its coffee. addicted? the only withdrawel symptoms are headaches and nausia, i dont think its really that much of a problem.
Ethan, the CEO of Starbucks has a net worth of over a billion American dollars and as a company Cost’s Coffee had an income of over 340 million pounds sterling for 2010/11. Coffee is big business, has potentially serious health risks and is addictive yet legislatively speaking isn’t in balance with other similarly unhealthy and addictive substances.
Seriously? People like coffee. I like coffee. Why would you make it illegal?
People are capable of making their own decisions. Either way, making things illegal hasn’t ever eliminated a controlled substance…just makes it more expensive to acquire. Heroin is illegal, but somehow people still get it.
Do you really want the government to control every aspect of your life?
First, you’re right about caffeine having a half-life of around 6 hours. If you consume 200 mg of caffeine, you’d still have 100 mg in you after 6 hours. Compromised liver function increases half-life by slowing metabolism. However, that 168-hour value is bullshit. The elimination kinetics of a drug in the plasma is determined by a process called feathering or curve stripping. When the plasma levels are measured with equipment that’s very precise, you sometimes get extremely long half-lives in spite of drug concentration being low enough to be clinically irrelevant.
Excess caffeine consumption is dangerous, and the tolerance we build to it doesn’t help. I just wanted to clarify some pharmacokinetic details though.
Finally, I like coffee a lot too. Can’t imagine giving it up!