Eatin' Like a Cretan.
(Lane3 is going to get some vindication from this I can see.)
Note: Angiogenesis is bad. Apoptosis is good. The former is a proliferative mechanism for cancer cells, and the latter a means by which they die.
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Glutathione.
The protective role of glutathione as an antioxidant and detoxifying agent has been demonstrated in various clinical studies. It is a ubiquitous compound that is synthesized rapidly in the liver, kidney and other tissues, including the gastrointestinal tract. In animal cells, glutathione acts as a substrate for glutathione peroxidase, which reduces lipid peroxides that are formed from PUFA in the diet, and as a substrate for glutathione S-transferase, which conjugates electrophilic compounds.
Recent studies showed that glutathione obtained from the diet is directly absorbed by the gastrointestinal tract and thus dietary glutathione can readily increase the antioxidant status in humans (91 Citation ).
Dietary glutathione, in addition to that supplied by the bile, may be used by the small intestine to decrease the absorption of peroxides.
These results indicate that in intact animals, lumenal glutathione is available for use by the intestinal epithelium to metabolize peroxides and other reactive species and to prevent their transport to other tissues.
Dietary glutathione occurs in highest amounts in fresh meats and in moderate amounts in some fruits and vegetables; it is absent or found only in small amounts in grains and dairy products (92 Citation ).
Only fresh asparagus (28.3 mg/100 g) and fresh avocado (27.7 mg/100 g) were higher than purslane in glutathione content in a study by the National Cancer Institute that determined the glutathione content of 98 food items that contribute 90% or more of energy, dietary fiber and 18 major nutrients to the U.S. diet (92 Citation –94 Citation ).
The potential health effects of dietary intake of glutathione in humans are shown in Table 6Citation (90 Citation, 95 Citation –103 Citation ). In a recent study by Flagg et al. (104 Citation ), plasma glutathione concentrations varied widely in humans and were influenced by sex and age (increased with age in men but decreased with age and were lower in women who used estrogen-containing contraceptives).
Table 6. Potential health effects of dietary glutathione in humans1
Glutathione is now known to be widely distributed in plant cells and is the major free thiol in many higher plants (105 Citation –108 Citation ). Considerable variations in levels of glutathione have been reported by different studies recording thiol levels in a variety of plant species. This may be due in part to the use of different analytical techniques and because glutathione levels vary both diurnally (109 Citation, 110 Citation ) and with developmental and environmental factors (111 Citation –113 Citation ).
Taking into account these considerations, the levels of glutathione found in purslane, 14.81 ± 0.78 mg/100 g fresh weight, were in the range of those reported for other plant species but significantly higher than the level of 9.65 ± 0.62 mg/100 g fresh weight for spinach (Table 7 Citation ) (38Citation ). Glutathione was present in significantly greater amounts in chamber-grown purslane relative to wild plants, which may reflect a difference in the developmental stage of the plants analyzed or in the environmental conditions experienced.
Table 7. Glutathione content of purslane and spinach leaves 123
In summary, many of the components of the diet of Crete—fiber, natural antioxidants from wild plants, fruit, wine, olive oil, a low ratio of (n-6) to (n-3) ratio (consistent with the Paleolithic diet)—have been shown, when studied separately, to potentially prevent cancer initiation or metastasis, prevent angiogenesis and induce apoptosis.
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