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L-Leucine as a Transporter?

Would L-Leucine be a good transporter for creatine with a meal?If it increases protein intake into muscle I wonder if it would do the same for creatine.

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[quote]bushidobadboy wrote:

Just don’t eat too much fat with your leucine.

BBB[/quote]

Way to take the fun out of it BBB!

[quote]bushidobadboy wrote:
It’s not a ‘transporter’ as such, though I think I know what you mean.

Instead, leucine is pro-insulinogenic, meaning it creates an insulin response. This insulin response can be used to signal the muscles to uptake creatine (as well as other stuff).

Just don’t eat too much fat with your leucine.

BBB[/quote]

Yo, smart guy…

I was reading (okay, skimming) some studies and it sounded like leucine only caused a minor and transient rise in insulin, which if you’re taking it with meals, you’re going to get anyway no matter what you’re eating.

So, is the insulin/fat scenario even worth worrying about? Curious about your thoughts.

Thanks!

I think Glycemic Load should be the only factor in considering the whole C+F macro combination being detrimental to body composition.

I think it is otherwise overrated since the majority of folks seem to only eat super low GI/GL carbs throughout the day, and little to no fat PWO. Hence, the rise in insulin from carbs shouldn’t be enough to worry about it storing more fat.

Besides, where does the fat you intake go anyway, without a rise in insulin? It circulates in the bloodstream and is stored in adipose tissue regardless, if it is not used up immediately by the body. No?

[quote]PonceDeLeon wrote:

Besides, where does the fat you intake go anyway, without a rise in insulin? It circulates in the bloodstream and is stored in adipose tissue regardless, if it is not used up immediately by the body. No?[/quote]

In any event, insulogenic amino acids and fatty acids are a minor part of the secretion of insulin, and I would imagine that the minor insulin response would not lead to a large enough activation of Lipoprotein Lipase to enhance fatty acid entrance into adipocytes.

If blood glucose is kept low, glycerol levels in cells should also be low, which theoretically should result in a decreased chance of these fatty acids combining with glycerol and being stored as triglycerides.

I would imagine it would be a total non issue if operating under a caloric deficit. I don’t know how truly it affects nutrient partitioning when operating under a caloric surplus.

Eating ANYTHING will cause some sort of insulin response. Will leu cause more of an uptake than creatine in water? Sure. Would you be better of with a P+C meal and maybe some Leu sprinkled in for good measure? Undoubtedly.

S

[quote]SBT wrote:
bushidobadboy wrote:
It’s not a ‘transporter’ as such, though I think I know what you mean.

Instead, leucine is pro-insulinogenic, meaning it creates an insulin response. This insulin response can be used to signal the muscles to uptake creatine (as well as other stuff).

Just don’t eat too much fat with your leucine.

BBB

Yo, smart guy…

I was reading (okay, skimming) some studies and it sounded like leucine only caused a minor and transient rise in insulin, which if you’re taking it with meals, you’re going to get anyway no matter what you’re eating.

So, is the insulin/fat scenario even worth worrying about? Curious about your thoughts.

Thanks![/quote]

That was my impresssion. Leucine is also a ketogenic and not glutagenic amino acid.

[quote]NewDamage wrote:

If blood glucose is kept low, glycerol levels in cells should also be low, which theoretically should result in a decreased chance of these fatty acids combining with glycerol and being stored as triglycerides.
[/quote]

Yes, but what happens to to the fatty acids eventually if they are not immediately used up? Are they not stored somewhere?

If not stored as triglycerides, where are they stored?

[quote]PonceDeLeon wrote:

Yes, but what happens to to the fatty acids eventually if they are not immediately used up? Are they not stored somewhere?

If not stored as triglycerides, where are they stored?[/quote]

I would imagine you are correct in that they are stored, but they just may not be stored as efficiently as they would be if insulin and blood glucose were present in large amounts. They may be stored, and released again quickly for fuel as they are needed. But I don’t know for sure.

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[quote]bushidobadboy wrote:

This echoes my own thinking. Fatty acids in the blood will be stored very efficiently in the face of elevated insulin. However, if insulin is moderated, then more of the fatty acids will be left in the circulation to be used as fuel.

BBB[/quote]

I don’t mind echoes from people whose knowledge I respect :slight_smile:

How long would you say the acidy fat bastards…I mean the fatty acids circulate in the bloodstream, waiting to be used up, before they are eventually stored?

Or would you say they are left circulating in the blood for a long time? Certainly not indefinitely, I think.

This is definitely a topic I have not seen addressed explicitly by any author, and I feel is the limit of the average member’s nutritional knowledge if theirs is based mostly off of reading articles and not having done their own research…which is NOT a knock on anyone, as I squarely fall into this category myself. I just wish someone would actually speak on the matter. Berardi, Alan Aragon, Lyle McDonald, Lowery…even CT.

This is probably where pantethine might be of use to lower blood fats. Also, I believe AlCar has a similar effect.

[quote]PonceDeLeon wrote:
bushidobadboy wrote:

This echoes my own thinking. Fatty acids in the blood will be stored very efficiently in the face of elevated insulin. However, if insulin is moderated, then more of the fatty acids will be left in the circulation to be used as fuel.

BBB

I don’t mind echoes from people whose knowledge I respect :slight_smile:

How long would you say the acidy fat bastards…I mean the fatty acids circulate in the bloodstream, waiting to be used up, before they are eventually stored?

Or would you say they are left circulating in the blood for a long time? Certainly not indefinitely, I think.

This is definitely a topic I have not seen addressed explicitly by any author, and I feel is the limit of the average member’s nutritional knowledge if theirs is based mostly off of reading articles and not having done their own research…which is NOT a knock on anyone, as I squarely fall into this category myself. I just wish someone would actually speak on the matter. Berardi, Alan Aragon, Lyle McDonald, Lowery…even CT.

This is probably where pantethine might be of use to lower blood fats. Also, I believe AlCar has a similar effect.[/quote]

I recently wrote an article that addressed some of the issues being discussed, hopefully this clears things up:

http://avidityfitness.net/2008/09/24/carbs-and-fat-friends-after-all/

I can’t give a proven, demonstrated response on this but can say what my guess is.

On the one hand, an attempt at coming up with a simple (always good, when not oversimplified to being wrong) logical explanation of things might posit that all nutrients consumed must be takem up anyway, as they can’t maintain long residence in the blood, so what difference is made by issues of timing or amounts of insulin release, so long as there are no diabetic problems?

While that has an appeal to it, in practice it doesn’t seem correct that there is no difference.

One reason could well be that the body can, but does not necessarily do so or does not have to do so to the same degree, adjust metabolic rate in response to intake of energy. In other words, eating more than what had been maintenance does not necessarily mean the surplus (relative to that) must all be stored as fat or even necessarily that any of it must be.

Suppose it is the case that if a large insulin spike drives fatty acids into adipose tissue this has little effect on increasing energy expenditure, but if the muscles take it up then energy expenditure increases. And suppose in a given individual that the insulin sensitivity profile is such that with a given amount of fat/carbs intake if the spike is large, the lion’s share goes to adipose tissue but if modest, more preferentially to the muscle.

I am not saying that this is so, but rather using it as an example that there may be mechanisms that if understood, would explain how it is that it isn’t so that “total calories per day is total calories per day” as the be-all, end-all of whether fat is gained or lost, as the most simplistic sort of model would have it. (Also certainly not saying that you were proposing that oversimplified of a model.)