oxalic acid (MR. BMJ)

[anthrax]

MR. BMJ, you said

Sweet potatoes have a lower GI rating due to its oxalic acid content.

so adding parsley or eating spinach (which are both rich in Oxalic Acid) would lower the GI of a meal ?

How much is it effective in lowering the GI ?

 

[MR. BMJ]

Yes, it should lower the GI as it inteferes with the amylase enzyme. However, it is an anti-nutrient and binds with minerals such as calcium and potassium and other divalent cations, thus inhibiting their absorption. Therefore, if supplementing or eating foods high in oxylates for a meal, you should try to keep your high calcium and potassium meals for a different time. Only about 5% of the calcium in spinach (frozen = 600mg; boiled = 750 mg oxalates) is absorbed. Other foods high in oxylates are rhubarb (600-860 mg), chard (Swiss: 645 mg), and beet greens (500-675 mg's). Oxalic acid binds with the calcium forming calcium oxylate, which is then insoluble
for absorption.

Other anti-nutrients such as tannins and phytates/phytic acid do this as well. Phytic acid is the strongest of the three in lowering the GI of foods. However, it too inhibits minerals such as calcium from getting absorbed. I believe there was a study showing that Phytic acid halved the GI rating of wheat bread, but I would have to search it out to find it.

Cocoa powder (623 mg) and pepper (419 mg) also have high oxylate contents. Peanuts (187 mg); Pecans (202 mg); plain chocolate (117 mg); okra (146 mg) soybean crackers (207 mg); and wheat germ (269 mg).

BMJ

 

[anthrax]

Some food preparation inhibits phytic acid action like Lacto-Fermentation

and always eat Naturally Leavened Bread