Mead Acid Production / PUFA Intake

[jellog]

When PUFA intake drops down to a minimum, how long does it take for mead acid production to begin? Is it fairly quick, or does the body have to run through it's "PUFA Stores" if such a thing exists?

When consuming PUFA, what's the upper limit of consumption that might still allow for mead acid production? At an intake of 2500kcal, 5 grams of total PUFA would be around 1.8% of the dietary calories -- how far away is this from "essentially fatty acid deficiency" ? Do any of the polyunsaturated fats have differing effects on mead acid synthesis? (Eg. is there a difference for inhibiting mead acid production if that was primarily omega-6 from animal fat, vs omega-6 from plant fat, vs omega-3 from plant fat, vs omega-3 from animal fat?)

 

[CoolTweetPete]

This is very interesting to me! When I initially read Roddy's book I tried looking up Mead acid and was unable to find a lot of information on it (particularly the health benefits).. Ray explained why in one of his posts, I think...

The Wikipedia page briefly speaks about it's role in inflammation, but also mentions something about it decreasing osteoblastic activity. I'm having trouble deciphering whether that is a good or bad thing, lol.

https://en.wikipedia.org/wiki/Mead_acid

 

[schultz]

From the studies I have seen, 1% PUFA seems to be the common minimum "requirement" for animals. You will still be making mead acid at 2 and 3% PUFA but below 1% is where is starts to take off. I think the standard way of measuring deficiency is still the triene:tetraene at 0.4. When PUFA is low (at 1% or under) cholesterol increases the ratio (increases deficiency). I don't know where to get cholesterol though . Hydrogenated coconut oil also increases the ratio.



Quote below from this study... http://jn.nutrition.org/content/55/2/337.full.pdf

"The effect of the addition of hydrogenated coconut oil to the otherwise fat-free diets of rats has resulted in the depletion of essential fatty acids in a shorter time interval and at a lower animal weight than when the rats were fed a fat-free diet alone. However, the continued presence of hydrogenated coconut oil in the diet had no apparent inhibitory effect on the subsequent response of the animal to linoleate although the animals depleted with hydrogenated coco nut oil in the diet had a greater growth potential than the animals depleted on the fat-free diet.
In rats receiving diets deficient in essential fatty acids, there was an increased cholesterol concentration in the liver and a decreased cholesterol content in the plasma after one week. However, although the condition was further aggravated thereafter in the animals on the fat-free diets, cholesterol levels of the rats receiving hydrogenated coconut oil in the diets gradually returned to normal. This effect may be due to the availability of short-chain fatty acids contained in the hydrogenated fat for esterification of cholesterol."

Below shows the effect of HCO on metabolism. Notice the 25% HCO group had the highest food intake and the lowest weight gain and therefore the lowest caloric efficiency. All animals had the same calorie intake. This is the sort of thing that flies in the face of the people who say that a calorie is a calorie because these animals ate more and gained less.

 

[schultz]

post 103965 This is very interesting to me! When I initially read Roddy's book I tried looking up Mead acid and was unable to find a lot of information on it (particularly the health benefits).. Ray explained why in one of his posts, I think...

The Wikipedia page briefly speaks about it's role in inflammation, but also mentions something about it decreasing osteoblastic activity. I'm having trouble deciphering whether that is a good or bad thing, lol.

https://en.wikipedia.org/wiki/Mead_acid

The authors of that paper were studying cartilage in young animals. Mead acid is present in the cartilage of animals and is especially high in the cartilage of young animals. The authors of that paper thought that the mead acid might be there to prevent ossification of the cartilage, which would basically turn the cartilage to bone, and therefore protecting the cartilage. Mead acid might have beneficial effects in preventing calcification of certain tissues. I'm not sure if there has been a paper studying its effects on actual bone health.

 

[DaveFoster]

From the studies I have seen, 1% PUFA seems to be the common minimum "requirement" for animals. You will still be making mead acid at 2 and 3% PUFA but below 1% is where is starts to take off. I think the standard way of measuring deficiency is still the triene:tetraene at 0.4. When PUFA is low (at 1% or under) cholesterol increases the ratio (increases deficiency). I don't know where to get cholesterol though . Hydrogenated coconut oil also increases the ratio.

Is that 1% of total calories or 1% of calories from fat?

If the former, that's insane and impossible. I'd guess the latter.

With 1320 calories from OJ concentrate, 96 oz skim milk, and 12 TBSP coconut oil (which is quite a bit), that's 2.22% percent PUFA.

Someone needs to find a source for fully-hydrogenated coconut oil.

 

[Such_Saturation]

Is that 1% of total calories or 1% of calories from fat?

If the former, that's insane and impossible. I'd guess the latter.

With 1320 calories from OJ concentrate, 96 oz skim milk, and 12 TBSP coconut oil (which is quite a bit), that's 2.22% percent PUFA.

Someone needs to find a source for fully-hydrogenated coconut oil.

Not exactly a low fat diet there...

 

[Luann]

Is that 1% of total calories or 1% of calories from fat?

If the former, that's insane and impossible. I'd guess the latter.

Yeah it is total calories lol.

Potato hacking? That's about 13 Pufa calories for 2870 total... 1 percent PUFA on the same diet would be 28.7. Potato hacking nets you .5 % PUFA calorie. Throw in some sugared skim milk for calcium, simple sugar, protein and the percent of energy to PUFA goes up even further.

 

[DaveFoster]

Yeah it is total calories lol.

Potato hacking? That's about 13 Pufa calories for 2870 total... 1 percent PUFA on the same diet would be 28.7. Potato hacking nets you .5 % PUFA calorie. Throw in some sugared skim milk for calcium, simple sugar, protein and the percent of energy to PUFA goes up even further.

I meant to say the latter would be insane and impossible.

Do you tolerate potatoes well? They always wreak havoc on my gut; strong thyroid function seems to be necessary.

 

[Luann]

Oh. That's right you did say once that you have tried VLF? That is probably true, I no longer eat potatoes, felt that the iron content would be high and I'd like to limit that while cutting PUFA...which should keep desaturases from going all crazy town.