>http://www.rhealiving.com/other_articles_links/High_protein_diet_increases_
antioxidants.htm

At the site, its pretty hard to read with the background, so here it (the
abstract) is in black and white.

Marilyn

. . .

Long-term high protein intake does not increase oxidative stress in rats [In
Process Citation]

Petzke, K. J., Elsner, A., Proll, J., Thielecke, F., Metges, C. C.

Journal of Nutrition 2000; 130: 2889-2896

The maximum dietary protein intake that does not cause adverse effects in a
healthy population is uncertain. We tested whether a high protein intake
enhances oxidative stress. Adult rats were adapted to different casein-based
diets containing either an adequate (13.8%; AP), medium (25.7%; MP), or high
(51.3%; HP) level of crude protein; a fourth group received a HP diet but no
RRR-alpha-tocopherol acetate (HP-toc). After 15 wk of feeding, plasma
protein carbonyl concentration, liver lipid peroxide levels [thiobarbituric
acid-reacting substances (TBARS)], reduced glutathione (GSH) status and
leucine kinetics ([1- (13)C]leucine) were measured. Higher concentrations of
protein carbonyls and TBARS were found in rats fed the AP and the HP-toc
diets compared with those fed the MP and HP diets (P: < 0.05). GSH
concentrations in plasma did not differ but total blood GSH concentrations
were significantly (P: < 0.05) lower in rats fed the HP- toc diet compared
with those fed the AP, MP and HP diets. Liver GSH concentrations were
significantly (P: < 0.01) lower in rats fed the AP diet compared with the
other groups. Rates of postabsorptive leucine oxidation (LeuOX) and flux
(Q(Leu)) were positively correlated with the dietary protein level (for AP,
MP, and HP, respectively: LeuOX, 74.9 +/- 28.5, 109 +/- 35.2, 142.3 +/- 38.4
&mgr;mol/(kg. h); Q(Leu), 425 +/- 102, 483 +/- 82, 505 +/- 80 &mgr;mol/(kg.
h). Only HP-toc resulted in a significantly greater protein breakdown
(PB(Leu)) and Q(Leu). No difference was seen in nonoxidative leucine
disposal. Long-term intake of high protein diets did not increase variables
of oxidative stress, in contrast to our initial hypothesis. An unexpected
finding was that adequate protein feeding (AP) may in fact induce oxidative
stress.

. . .