Sunday, February 23, 2020

Lard makes hungry mice live longest

Over the past few weeks I've been looking for papers where Barja's group might have run longevity experiments. This does not seem to have been their forte. They have done lots of observational comparative studies looking at long vs short lived species and lots of interventions to modify mitochondrial membrane lipid composition but no hard-core lifespan measuring studies that I can find.

So Barja threw in the rather off comment about avoiding "excessive intake of animal proteins and fats typical of western diets" in his review without obvious direct testing of these variables on lifespan.

I have to leave the mechanism of calorie restriction, aka protein restriction, aka methionine restriction for another day.

What we can do today is to look at Barja's dreaded animal fats. Like lard.

The data are, sadly, only available from CRON fed mice. This is the study:

The Influence of Dietary Fat Source on Life Span in Calorie Restricted Mice

Diets had their fat source modified thus and also had their calories restricted by 40%:

"The modified AIN-93G diets (% of total kcal) each contained 20.3% protein, 63.8% carbohydrate, and 15.9% fat. Soybean oil was the dietary fat in the control group (standard AIN-93G diet). The dietary fats for the CR groups were soybean oil (high in n-6 fatty acids, 55% linoleic acid, Super Store Industries, Lathrop, CA), lard (high in monounsaturated and saturated fatty acids, ConAgra Foods, Omaha, NE) and fish oil (high in n-3 PUFAs, 18% eicosapentaenoic acid, 12% docosahexaenoic acid, Jedwards International, Inc., Quincy, MA). To meet linoleic acid requirements, the fish oil diet contained 1% (w/w) soybean oil".

Here are the survival curves:

The left hand curve of green circles is from (nearly) ad-lib feeding of crapinabag. The yellow squares showing best survival are from feeding the dreaded animal fats from lard, combined with CRON. The fish oil group, full of EPA and DHA, did worst of the three CRON groups with soy oil being intermediate.

I think beef dripping would have done better than lard and beef suet even better still, but then I would think that.

Peter, saturophile.


Justin said...

Thanks for posting! That paper is money! I've been rendering my own beef tallow lately as the neighbor kid works in the meat department and gets pounds of it for free. I wish he could get some from grass fed cows, but I'm not complaining as I already consume a lot of Kerygold. Have you ever used rendered lamb/mutton fat? I keep hair sheep, but have not enjoyed my own yet (just sell them off the farm). I might have to see if he can get some lamb trimmings so I can try it out.

Unknown said...

"linoleic acid *requirements*" lol :)

Peter said...

Justin, I can get lamb ribs/skirt from Morrisons. Very fatty. Lamb hearts come with a reasonable fat load too.

Unknown, yep, sigh!


Justin said...

Peter, I forgot about the ribs. They are super fatty and cheap. I'll pick some up and try it out. Thanks!

Puddleg said...

I like this paper - these guys are saturophiles. I had the privilege of peer reviewing something else they wrote, but the editor rejected it - hope they got my notes.

Peter said...

Hi George,

Having at least one decent scrutineer is always worth while! In the Chinese paper I struggle to see why the blended oil was better than the lard alone. You would have thought the problems from soy oil would be in direct proportion to the amount of it in the diet...


Tucker Goodrich said...

Fascinating paper. Points to Peat, for warning about Peat, and to the Inuit, for their CPT1a mutation thought to possibly be protective against excess n-3.

Demerits to every lab on Earth to keeping malnourished, unhealthy rodents as their model.

Number one paper I would like to see is an analysis of the diet of a mouse in the woods. Sigh.

Tucker Goodrich said...

*For warning about fish oil!


Jonathan said...

Yes, it is good to have a citation to point to for the downsides of too much fish oil. I too have wondered about that since reading Ray Peat's thoughts about it more than a decade ago.

Passthecream said...

Peter, do you render your lamb ribs or just eat them as-is?

Unknown said...

Not surprising. DHA and EPA are even more reactive than LA. Not good. What would be surprising would be to see theDHA/EPA group doing best.

Tucker's comment about the diet of wild mice is apropos. It seems unlikely that wild mice were ever exposed to so much DHA/EPA, and therefore would not have evolved countermeasures.

Justin said...

Speaking of lamb, just had our first of the season. This girl threw tripplets last night. Two rams and a ewe. My freezer is going to be full come this fall. Lol. Warning, video is not for the faint of heart and Ia for spamming your thread Peter.

ashe higgs said...
This comment has been removed by the author.
ashe higgs said...

N-6 fatty acids are still essential, just not in the massive quantities you get them in industrial seed oils