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Biotech Science

Why It's So Hard To Predict How Caffeine Will Affect Your Body 212

carmendrahl writes "Emergency-room visits linked to caffeine-laden energy drinks are on the rise. This gives scientists who'd like to see caffeine regulated the jitters. But the U.S. Food and Drug Administration seems to be dragging its feet on regulating caffeine content in food and drink, because people have different sensitivities to it (abstract). Currently, caffeine-rich products like Monster Energy get around the rules because they're marketed as dietary supplements. 'Caffeine gets cleared from the body at different rates because of genetic variations, gender, and even whether a person is a smoker. For this reason, it’s difficult to set a safe limit of daily consumption on the compound. Physiological differences, as well as differences in the way people consume caffeine, have tied FDA in knots as it has debated how to regulate the substance. ... The toxic level in humans, about 10 g, is roughly the equivalent of imbibing 75 cups of brewed coffee (in 8-oz mugs) or 120 cans of Red Bull over a few hours. But that lethal limit can vary widely from person to person, experts say."
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Why It's So Hard To Predict How Caffeine Will Affect Your Body

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  • Toxic level (Score:5, Informative)

    by Anonymous Coward on Monday February 04, 2013 @05:54PM (#42789881)

    The toxic level in humans, about 10 g, is roughly the equivalent of imbibing 75 cups of brewed coffee (in 8-oz mugs) or 120 cans of Red Bull over a few hours.

    According to the eminent Wikipedia [], that's the LD50 (150 to 200 mg/kg).
    If you gave an average group of humans 10g of caffeine, half of them would die.

    Now LD50 is a way to measure of toxicity, but I think it's fair to assume that a substance is toxic well below the lethal dose.

  • Re:Um... (Score:4, Informative)

    by Brian Feldman ( 350 ) <(gro.DSBeerF) (ta) (neerg)> on Monday February 04, 2013 @06:50PM (#42790715)

    fat soluble chemicals never actually leave (like LSD), they just get stored away in the alrd region

    This is wrong. Lysergic acid diethylamide is broken down by monoamineoxidase. This is just like the myth of LSD being stored in your spinal fluid and causing flashbacks or the one of THC being stored in your fat and getting you high when you exercise -- completely baseless.

  • by hierophanta ( 1345511 ) on Monday February 04, 2013 @07:00PM (#42790857)
    This is actually scientifically not true. Caffeine affects us by blocking the chemicals that make us tired. As a result we are not only feeling more awake, but actually are more awake. The crash that occurs is because the chemicals that have been blocked thus far, are in a waiting pattern until their blockage disappears after which they flood the receptors. I do agree though, there is a good amount for false positive when it comes to perceived performance though.
  • by nabsltd ( 1313397 ) on Monday February 04, 2013 @07:09PM (#42790993)

    I can drink a red bull, a monster, a coke, tea, or anything but coffee and easily take a long nap afterwards. Something about the caffeine I get through coffee is different.

    Depending on how it is prepared, coffee can have more caffeine than Red Bull, and definitely has more than Coca-Cola and the vast majority of teas. See this table [] for details.

    You can also do some searching and see that the "caffeine" in various substances isn't always the real thing, but instead is closely related compounds.

  • by Obfuscant ( 592200 ) on Monday February 04, 2013 @07:10PM (#42791013)

    Put this stupid myth to rest.

    You mean the myth that using fructose in place of sucrose makes no difference?

    The simple fact that a simple sugar has already been broken down to a simple sugar means that it will flood the system much more quickly than a more complex sugar that needs to be converted before transport. If we don't need to pay attention to what the sugars are, then explain why cellulose (long chains of glucose) are indigestible, while simple glucose floods the system almost as soon as it is ingested.

    Yes, sir, the metabolic paths for glucose and fructose are different, and flooding the liver with massive amounts of fructose rapidly does result in a different effect than a slower appearance of glucose. The liver and endocrine systems need time to react to the influx of the sugars no matter what they are, so a rapidly appearing slug of one kind of sugar can easily overwhelm the regulatory mechanisms of the body and cause harm where a slower appearance of a different sugar does not. That harm may only be an unnecessary conversion of sugars to glycogen and fat, but in the long term that results in obesity and that can be harmful.

    You're talking to a diabetic who has monitored his blood sugar for years through all kinds of experiments with different sugars, who can tell you that the "glycemic index" and "sugar alcohols" information is a truly dangerous myth, along with the sugar industry shills telling us that there is no danger from HFCS. Yes, you're right that cutting sugar overall is a good thing, but trying to claim that if you are going to down a sugar laden drink that it makes no difference is just parroting the sugar industry media flacks. You'd point to data denying global warming or the link between smoking and cancer as being from an industry source, why are you so quick to accept data from the sugar industry?

  • Ephedra... (Score:4, Informative)

    by Ellis D. Tripp ( 755736 ) on Monday February 04, 2013 @07:36PM (#42791345) Homepage

    Ephedra disappeared from the market because of negative press coverage of several stupid athletes who abused it.

    Personally, I think that the War on Drugs had a lot more to do with that. Ephedra (and the active alkaloid, ephedrine) can be used as precursors for methamphetamine manufacture. The FDA yanked ephedra and ephedrine products about the same time that the DEA rammed through the laws requiring you to put your name into a federal database to buy a package of cold/allergy pills.

  • by jones_supa ( 887896 ) on Monday February 04, 2013 @07:43PM (#42791427)
    More specifically, the chemical is adenosine.
  • Re:Just tax it. (Score:3, Informative)

    by Insanity Defense ( 1232008 ) on Monday February 04, 2013 @09:20PM (#42792377)

    Not for everyone. For some people (like myself) the problems caffeine cause are subtle and work in combination with other things. With caffeine in my system I'm allergic to perfume, cigar and pipe smoke and sunburn in 15 to 20 minutes. Caffeine alone does nothing obvious but add any of the other things and my health goes to hell with the appearance that it is the 2nd thing causing it alone. Only by accident did I learn of the caffeine connection and solve my lifelong health problems.

  • by zebadee ( 551743 ) on Monday February 04, 2013 @09:25PM (#42792427) Homepage

    The other effects like jitters and palpitations is probably harmful to the heart in the long term

    Caffeine (at high) doses can cause heart problems much more acutely. We have shown that 0.3mM caffeine (equivalent to ~2.3g*) can modify the activity of a protein in the heart sufficiently to mimic the effect of herditary mutations capable of causing fatal arrhythmias and that effect is quick (within mins). []

    *Based on an average water volume of a 70kg man = 40L, caffeine = 194g/mole and all caffeine being absorbed.

Perfection is acheived only on the point of collapse. - C. N. Parkinson