I'll re-post something here from the old CR archives by MR. I'm sure he wont mind lol. It seems that high er fat or protein mice lived longer, had less cancer... It didn't do anything amazing to max lifespan, but only increase average a bit (still very good!). Hence why I increased my protein intake and decreased my carb. Note that 69% of energy from fat decreased lifespan in CR rodents

efore I take too much flak, note the QUESTION MARK at the end of my post.

I've been working my way thru' Weindruch and Walford's _The Retardation..._, which I have out on interlibrary loan. I knew that various macronutrient combos had failed to improve maximum lifespan gains, but just assumed (sicne I'd never heard anything either way on the subject) that no one had bothered looking at a broad variety of combinations and seeing what other health effects (esp. av'g LS) might accrue. It is Sears' thesis that any CRON will slow aging, but that the high P:C ratio will also give other benefits. As Sears presents it, it's a purely argumentative case, yet It appears we've had concrete experimental data showing something like this to be true for over three decades.

Op cit, p. 54: "Ross and Bras ... balanced the calorie intakes ... of rats subjected to EDR but varied the casein:sucrose ratio ... The average LS of the rats on DR increased as the amount of protein in the diet increased, suggesting that the effects of DR on LS may be enhanced by diets high in protein content. A later report (Davis et al, 1983) supports this view."

P. 81: "The DR rats fed the high protein diet [51% casein!] displayed a lower risk of developing malignant epithelial tumors than DR rats fed the low protein diet. Adrenal and thyroiid tumor morbidity both inversely related to dietary protin among the Dr groups. In short, BOTH LS AND TUMOR DATA SUGGEST THAT HIGH-PROTEIN DIETS ACCENTUATED THE BENEFITS OF DR [italics, presumably obviously, mine]."

p. 105: "the inhibition of skin tumors was greater for mice energy restricted ONLY VIA CARBOHYDRATES than for those restricted in all componenets [my italics]."

p.108ff: Data showing that a high-percentage fat diet does not increase tumors on CRON, even tho the form of fat used -- corn oil -- is acknowledged by W&W to be a particularily carcinogenic one when fed ad lib. If they used a balanced EFA mix, I wonder if it would show the REVERSE...?

OTOH, "Variation in proti\en level in dr MICE [my italics] did not alter longevity" -p.59.

Second post

"Kubo ... found that LSs were most strikingly prolonged by DR when moderate intakes (38% of energy as fat) and not very high intakes of fat (69% of energy of fat) were used." p. 59

"High fat diets are used more efficiently than are low fat ones... Quite probably the severity of the [CR] tolerable by animals could be increased by feeding high fat diets... whether this would further increase lifespan is worthy of study [see above quote: evidently, it DOES] ...*what* (not just how much) is eaten affects metabolism." -255

Third post

the rodent data suggest that the most benefits are derived, IN RODENTS, from a relatively high-protein, high-fat diet, with minimal carb -- ie, a much more "Zoneish" diet that W&W actually reccomend for human experimentation. This seems a case of refusal to acknowledge the data before them. And it gives a concrete level of support for Sears' (purely argumentative) case that the Zone program (or something rather like it) would give additional health and longevity benefits over and above the increase in max lifespan to be had from some other CRON program. Compared to 51% pro and 38% cho, even SEARS' reccomendations seem conservative, let alone Walford's!

Also, as I've noted before, the Zone is based on a high (~0.75) P:C ratio, NOT a specific 40:30:30 diet for all (as the folks at Balance Bar and People magazine would have us believe). In _Mastering..._ and _The Anti-Aging Zone_, Sears spells this out quite clearly, stating how and why to alter the p, c, and f in your diet to hit the right proportions for each individual, based on both subjective and objective criteria

The animals LIVE LONGER on a higher-fat (38%!) diet
than a lower (or higher (61%)) one.