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Tony Ferous
12-12-2008, 04:01 AM
I found this very interesting...


http://www.whfoods.com/genpage.php?tname=foodspice&dbid=25

Grapefruit juice significantly increases the production and activity of liver detoxification enzymes responsible for preparing toxic compounds for elimination from the body.

The liver clears out toxins, including carcinogens, using a two step process called Phase I and Phase II detoxification. In the first part of this process, Phase I, enzymes belonging to the cytochrome P450 family, work on the toxin to make it more attractive to enzymes involved in the second part of the process, Phase II. Unfortunately, the action of Phase I enzymes often renders the toxin not only more attractive to Phase II enzymes, but even more dangerous, and some foods contain compounds that only increase the activity of Phase I without also turning up Phase II.

Grapefruit increases the activity not only of the Phase I enzyme CYP1A1, but also that of NAD(P)H:quinone reductase 1, a Phase II detoxification enzyme that protects cells against oxidative stress and toxic quinones.

The end result: grapefruit works in both Phase I and Phase II to enhance the liver's ability to remove cancer-causing toxins



And from www.cancer.gov
phase I detoxification

A process in which the liver uses one of two major enzyme pathways to change a toxic substance, such as an anticancer drug, into a less toxic substance that is easier for the body to excrete.

phase II detoxification

A process in which the liver uses one of two major enzyme pathways to change a toxic substance, such as an anticancer drug, into a less toxic substance that is easier for the body to excrete. In phase II detoxification, liver cells add a substance (such as cysteine, glycine, or a sulfur molecule) to a toxic chemical or drug, to make it less harmful.

George Mounce
12-12-2008, 04:52 AM
I love to eat grapefruit, and do quite often, so glad to know I'm keeping my system clean!

Ari Kestler
12-12-2008, 11:06 AM
This isn't as clear cut as it seems. You can'teat more grapefruit and detoxify your system any more so than if you don't. Moreover, be wary of excess grapefruit consumption and any prescribed drugs you may be on. It can do funny things by playing with your liver processes.

Garrett Smith
12-12-2008, 11:42 AM
This is an important part:
Unfortunately, the action of Phase I enzymes often renders the toxin not only more attractive to Phase II enzymes, but even more dangerous, and some foods contain compounds that only increase the activity of Phase I without also turning up Phase II.
Alcohol is an important compound that does exactly what that sentence says. The backup of metabolites spills out into the system because the Phase II can't keep up with Phase I. Well known as a hangover.

Ari, it is exactly the effect of grapefruit consumption on the liver that is why it effects drug metabolism. This would also affect other toxin-metabolizing processes that utilize cytochromes that grapefruit consumption is involved in. There are so many cytochromes that process so many things, that generalizing that grapefruit is good for general detox isn't necessarily true. It's good for speeding up certain processes. This can be good or bad, depending on the compounds (often referred to as "toxins") that the person is dealing with.

It's figuring out the differences and what approach is needed.

All that said, yeah, grapefruit is darn good for you.

Scott Kustes
12-12-2008, 11:45 AM
It's unfortunate it tastes like crap.

Blair Lowe
12-12-2008, 10:12 PM
bah, it tastes damn good, especially the rubies.