I asked BenaGene, a company that also sells Oxaloacetate, why, if citric acid directly metabolize to oxaloacetate, I should take its product rather than having a bit of lime juice every day. I received the following response:
Back when the “antioxidant” theory was big, there were several lifespan studies done with various antioxidants including Citric Acid (citrate) and ascorbic acid. There was no increase in lifespan.
While under certain conditions oxaloacetate can convert to citrate, and vice versa, it does not create the conditions we want. We want to flood the cellular system with oxaloacetate so that it converts to malate.
So why not just take a bunch of malate? (found in apples). It’s because during the conversion of oxaloacetate to malate, NADH also converts to NAD+. This increase in the NAD+/NADH ratio is the key to activating AMPK which leads to similar genomic changes similar to a calorie restricted state. These changes then lead to increases in lifespan.
On the other hand, lime juice is very helpful for making margaritas.....
This is an interesting line of reasoning, which is not easily refuted. It seems quite plausible biochemically, and my strongest attack on it would probably be through the conjunction fallacy—while each of these steps seems reasonable, perhaps the entire chain is faulty.
However, there is one thing that seems blatantly out of place—and that’s the scale of the process. The citric acid cycle as a whole operates at a catalytic concentration of 1-5 millimolar, in just about every cell of the body. Multiplied by 70 kg of weight per person, that would equal 70-350 millimoles, or roughly 10-50g of CAC intermediates in the body. If this pill is really hoping to dump enough oxaloacetate into the system in order to temporarily force the cycle to run backwards, a 100mg daily dose seems small. I would think you’d need at least 1g daily before it actually affects the citric acid cycle.
Do they teach science in school nowadays? I feel like the analysis that I’m doing should be doable by most scientifically literate people.
Resurrecting a long dead topic here. I have a BS in Chemistry and only learned about the citric acid cycle in my last semester as an undergrad. I doubt many physics, math or comp. sci. people are ever exposed to it so it may be that the analysis can be done fairly easily, but that most people don’t have the prior information to flag this as improbable.
In what quantity? How much citric acid would you have to take to get 100 mg of Oxaloacetate? Plus, all supplements sold without a prescription in the U.S. have to naturally exist within the body or be in “normal” foods. If resveratrol had proved to have anti-aging properties buying it wouldn’t be a ripoff even though resveratrol is in red wine.
47 grams per liter of lemon/lime juice. That converts to ~25 g oxaloacetate per liter. Oranges apparently have less citric acid, to the tune of perhaps 500mg oxaloacetate equivalent per liter of juice.
Food-grade citric acid (also sold under the name “sour salt”, usually shelved with spices) is FDA-classified as GRAS. Looking at Amazon, the Spicy World Citric Acid in the 5-pound bag is $19.23 (free shipping for me, since I have Amazon Prime).
At the ~2g of citric acid metabolizing into ~1g of oxaloacetate you suggest, that translates to a price of $0.05 per three grams of oxaloacetate, or three orders of magnitude cheaper than buying a bottle of 30 100-mg capsules for $49.
Oxaloacetate looks promising. (Lots of citations in the middle of the linked page.) It’s also for sale here.
Citric acid directly metabolizes to oxaloacetate in the body. This guy is selling you fruit juice at $50 bucks an orange.
I asked BenaGene, a company that also sells Oxaloacetate, why, if citric acid directly metabolize to oxaloacetate, I should take its product rather than having a bit of lime juice every day. I received the following response:
Back when the “antioxidant” theory was big, there were several lifespan studies done with various antioxidants including Citric Acid (citrate) and ascorbic acid. There was no increase in lifespan.
While under certain conditions oxaloacetate can convert to citrate, and vice versa, it does not create the conditions we want. We want to flood the cellular system with oxaloacetate so that it converts to malate.
So why not just take a bunch of malate? (found in apples). It’s because during the conversion of oxaloacetate to malate, NADH also converts to NAD+. This increase in the NAD+/NADH ratio is the key to activating AMPK which leads to similar genomic changes similar to a calorie restricted state. These changes then lead to increases in lifespan.
On the other hand, lime juice is very helpful for making margaritas.....
This is an interesting line of reasoning, which is not easily refuted. It seems quite plausible biochemically, and my strongest attack on it would probably be through the conjunction fallacy—while each of these steps seems reasonable, perhaps the entire chain is faulty.
However, there is one thing that seems blatantly out of place—and that’s the scale of the process. The citric acid cycle as a whole operates at a catalytic concentration of 1-5 millimolar, in just about every cell of the body. Multiplied by 70 kg of weight per person, that would equal 70-350 millimoles, or roughly 10-50g of CAC intermediates in the body. If this pill is really hoping to dump enough oxaloacetate into the system in order to temporarily force the cycle to run backwards, a 100mg daily dose seems small. I would think you’d need at least 1g daily before it actually affects the citric acid cycle.
Do they teach science in school nowadays? I feel like the analysis that I’m doing should be doable by most scientifically literate people.
Resurrecting a long dead topic here. I have a BS in Chemistry and only learned about the citric acid cycle in my last semester as an undergrad. I doubt many physics, math or comp. sci. people are ever exposed to it so it may be that the analysis can be done fairly easily, but that most people don’t have the prior information to flag this as improbable.
It’s been 25 years since I took chemistry.
In what quantity? How much citric acid would you have to take to get 100 mg of Oxaloacetate? Plus, all supplements sold without a prescription in the U.S. have to naturally exist within the body or be in “normal” foods. If resveratrol had proved to have anti-aging properties buying it wouldn’t be a ripoff even though resveratrol is in red wine.
http://en.wikipedia.org/wiki/Citric_acid#Occurrence
47 grams per liter of lemon/lime juice. That converts to ~25 g oxaloacetate per liter. Oranges apparently have less citric acid, to the tune of perhaps 500mg oxaloacetate equivalent per liter of juice.
Food-grade citric acid (also sold under the name “sour salt”, usually shelved with spices) is FDA-classified as GRAS. Looking at Amazon, the Spicy World Citric Acid in the 5-pound bag is $19.23 (free shipping for me, since I have Amazon Prime).
At the ~2g of citric acid metabolizing into ~1g of oxaloacetate you suggest, that translates to a price of $0.05 per three grams of oxaloacetate, or three orders of magnitude cheaper than buying a bottle of 30 100-mg capsules for $49.
Looks like the person peddling this stuff is basing it on mice studies.
There appears to have been clinical human trials which “show an average reduction in fasting glucose levels of 25% in Type I and Type II diabetics”.
Didn’t catch that, thanks. Might be worth a shot for people with elevated blood glucose (above 85mg/dl), very expensive though.
And nematode studies.