vitamin C bowel tolerance too low?

With either Metabolic C or PureWay C, if I take anything more than 500mg at once, I'll get diarrhea...

It's especially weird when I take a look at the original study that says that healthy people should tolerate 4000 to 15000 mg of vitamin C.

Also, I can easily take 2000 or 3000 mg LivOn lipospheric C at once (or possibly even much more, although the steep price is what holds me back with this brand...).

How does that make any sense???

Makes perfect sense because the vitamin C molecules become encapsulated inside a phospholipid membrane. They bypass the stomach's digestion and slowly get opened inside the GI tract and directly into the bloodstream vs. dumping all of it into your stomach (immediately disrupting the overall acid/alkaline balance.) I have taken the equivalent of 50g liposomal C in a day without any GI distress.

Liposomal vitamin C is also very cheap. Proof?

Lecithin: $22.99 for three lbs.
https://www.swansonvitamins.com/swanson-premium-lecithin-granules-non-gmo-3-lb-1362-grams-granules

Sodium ascorbate: $5.75 for 1/2 lb.
https://www.swansonvitamins.com/now-foods-sodium-ascorbate-8-oz-pwdr

Ultrasonic cleaner: I use this one.
http://www.ebay.com/itm/Industrial-220-Watts-3-liters-HEATED-ULTRASONIC-CLEANER-HB23-/310412468115

http://www.racehorseherbal.com/Infections/LET/let.html

Bam.

would you advice against trying the same liposoluble vitamin C recipe (adjusted for different molecular weight) for Calcium Ascorbate instead of plain Ascorbic Acid?

I just happen to have a large stock of Calcium Ascorbate...  

also, @4039: isn't that ultrasonic cleaner too large? It would take a while to consume a batch of 3 liters of liposoluble vitamin C, and it would go bad in the meantime... It doesn't look like the cleaner can be under filled either:

http://www.tovatech.com/blog/11021/ultrasonic-cleaner/how-to-pick-an-ultrasonic-cleaner wrote:
Don’t try to increase the effective power of an ultrasonic cleaner by under-filling the tank.  The generator on an ultrasonic unit is tuned to a particular fill level.  Operating the unit with less fluid can damage the generator and will result in less than optimized cleaning.

I've never tried calcium ascorbate. I imagine the formula would remain the same. I also make huge batches and store them in the refrig with some added astaxanthin to the finished product, never had a problem with spoilage.

How about not taking so much in the first place? Your intake seems fine, maybe add some lemon juice to your water during a meal, or consuming more fruit?

magic_gro - You might benefit from a buffered form.

4039 and others: is it that essential to use distilled water? where do you get it from? supermarkets sell it in plastic bottles... ugh... being distilled water, the plastic will leak like crazy into it...