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How is it that grapefruits affect medications and some vitamins when taken at the same time? A lot of things are labeled take with food. Isn’t grapefruit a food too?

One of the pathways for detoxification in the liver is referred to as the P-450 pathway.  Grapefruit competes for one of the P-450 receptors which is supposed to grab and start breaking down certain substances and clearing them from the body.  If grapefruit is tying up the receptor, the medication or substance in question may be permitted to be absorbed in tact to a greater degree and may result in higher blood levels.  This may affect some medications, but not others, depending on the specific mechanism of detoxification for each substance.

Food in general, doesn’t tie up the P-450 receptor. 

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(Note: as per industry regulations, we cannot and will not answer medical questions, make treatment or diagnosis recommendations or comment on disease inquiries. Such questions must be answered by your doctor or professional health care provider.)


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