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Is Ester-C the Best Form of Vitamin C? -- bottle of Ester-C


Regular vitamin C, ascorbic acid, is acidic. This is not the reason why high-dose vitamin C sometimes causes diarrhea, but the acidity can cause stomach irritation in some people. If you want a less-acidic vitamin C, you can choose Ester-C (calcium ascorbate) or sodium ascorbate. With each, vitamin C is attached to (and is "buffered" by) calcium or sodium. If you are watching your sodium intake, Ester-C would be preferable. However, there is no evidence of a significant difference in the absorption of any of these forms of vitamin C.

More details about these forms, as well as our Top Picks for vitamin C supplements based on our tests and comparisons, are found in the Vitamin C Supplements Review. The review includes information about other forms of vitamin C, such as slow-release, L-ascorbic acid, ascorbyl palmitate, "fully reduced," liposomal, and PureWay-C, which includes fatty acids.

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May 7, 2021

I have been taking the Ester-C (24-hour immune) because I have seasonal allergies. I'm not sure what it is but after I take it I get a reactive cough and throw up what appears to be the residual of the supplement. It's supposed to be stomach-friendly.

January 10, 2020

I have read that Absorbic acid is a synthetic form of vitamin C and that the natural form is much better. Can you comment on this?
January 10, 2020

Actually, acorbic acid is the natural vitamin and it can also be produced synthetically, as sold in many supplements.

January 10, 2020

Does the synthetic form go y another name? Also, how do you know if you are getting the synthetic or natural form?
February 11, 2020

Hi Doyle - The product label should say that the vitamin C is "from" a named natural source, such as rose hips. If it is synthetic it should say vitamin C "as" a named synthetic source, such as ascorbic acid.

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