Vitamin C, especially in the form of citrus, has been known to increase the absorbtion of medicines by as mutch as 5x. There are actually warnings about consuming these things at the same time or people will get an overdose.

Since most foods on the raw diet are loaded with vitamin C, wouldn't we be absorbing more nutrients generally than SADders, and if so, then the standard RDAs shouldn't apply to us? I.e., we shouldn't be concerned about meeting the RDAs that were developed for SAD diets or that were determined by using test subject that were eating a SAD diet.

I know that this doesn't apply to all nutrients since some aren't affected by Vitamin C.

any references?

[www.ncbi.nlm.nih.gov]

So I was reading my favorite book again yesterday, Left In the Dark, and it has some very interesting bits about Vitamin C.

(*allow me to paraphrase, ahem*)

There was research done saying that monkeys need about 55 mg of Vitamin C/kg of body weight--and, applied to humans, that's 3,850 mg/day for a 150 lb. person. My book says the RDA for humans is 45 mg (fitday says 60)--but that's still nothing compared to what our closest relatives are eating, between 2-6 grams/day.

This is critically important because the body concentrates vitamin C around the brain and spinal cord 100x its concentration in the rest of the body, to protect against free radical damage.

If you look at vitamin C RDAs in that light, and think about what it's actually doing for you... I'm quite happy to scarf down my fruit, thanks!

I don't know how this affects absorption of other nutrients, but I think it's critically important to note because A) it's protecting our precious CNS, which is clearly beginning to crack under environmental stress and our closest DNA relatives, eating high-fruit raw diets, are eating a TON of vitamin C. So, whatever it's doing for them (increasing nutritional uptake or not), it stands to reason, it SHOULD be doing it for us, too.

On raw, I've personally found it impossible not to get into the 1000%s of the RDA... but, good to know. =)

That was totaly interesting phantom about the monkeys eating grams of vitamin C a day! I've noticed that some vitamin C supplements that I've taken in the past had a huge amount of vitamin C, in the 1000% of the RDA so I guess that the vitamin companies know we need a lot.

Ok, I think I was confusing the enzyme acitivity of grapfruit with vitamin C when I said that citrus helps increase drug absorbtion by 5 x, but vitamin C is still a factor with increasing absorbtion of substances:

This is vitamin C interaction info from Medline Plus:
[www.nlm.nih.gov]
-Vitamin C may increase adverse effects associated with acetaminophen or aluminum-containing antacids such as aluminum hydroxide (Maalox®, Gaviscon®).
-When taken together, vitamin C may increase blood levels of ethinyl estradiol.
-Vitamin C in high doses appears to interfere with the blood thinning effects of warfarin by lowering prothrombin time (PT), as noted in case reports in the 1970s.
-Vitamin C may increase absorption of lutein vitamin supplements.
-In theory, large doses of vitamin C may also interact with herbs and supplements with hormonal, antibacterial and blood thinning (anticoagulant) activity.

It also decreases certain substances:
-Vitamin C supplementation may decrease levels of the drug fluphenazine in the body.
-Concomitant administration of high doses of vitamin C can reduce steady-state indinavir plasma concentrations.
-Large doses of vitamin C may interfere with the absorption and metabolism of vitamin B12.

But when you think about how the RDAs were set, they were set using SAD eaters I'm sure, and digesting meat and dairy has to take different nutrients than digesting produce. So, the research subjects would be digesting these things (that nature never meant for them to eat) and this would cause vitamin deficientcies.

An example of this would be a high protein diet causing an acidic condition and creating a calcium deficiency. The researchers would notice this calcium deficiency and set the RDA for calcium artificially high. But, if the test subjects had been eating a vegan diet, the calcium RDAs would have been set much lower.

I wonder how many other RDAs were affected by the type of diet the test subject ate? Do we have to look to the monkeys for our RDA guidelines?



Edited 1 time(s). Last edit at 07/03/2008 04:04PM by Lillianswan.