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I heard a lot of benefits to drinking grapefruit juice on a daily basis - from enhancing caffeine to magically eating away fat....does anyone have any hard evidence/studies supporting any of this?

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Grapefruit juice can increase the occurrence of kidney stones according to nearly every source. I just had them last month and it was the most excruciating pain I have ever felt. Every hour or so, my middle back would build up pressure until there was so much pain that my whole body went into shock for 15-20 seconds. Stay away from grapefruit juice if you don't want to feel like you're giving birth every hour. – JoJo Jul 27 '11 at 4:41
@JoJo Ouch!!!!! – Evan Plaice Jul 28 '11 at 17:50
up vote 6 down vote accepted

According to this article from the British Journal of Clinical Pharmacology, grapefruit juice prolongs the systemic elimination half-life of caffeine, i.e. the caffeine stays in your system for longer.

This article supports the claim that grapefruit products promote weight loss. It also says that grapefruit products improve insulin resistance in people with metabolic syndrome.

It's worth noting that grapefruit juice can have dangerous interactions with a number of drugs, so make sure you double check the safety information of any drugs you take before using grapefruit juice for its "magical" properties.

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+1 for the warning regarding medical interactions--they are very real and not at all "magical" – STW Jul 26 '11 at 17:00

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