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1 tablet = 1,000 mg + 102 mg citrus bioflavonoids
2 tablets = 1,000 mg + 204 mg citrus bioflavonoids
2 capsules = 1,000 mg + 400 mg citrus bioflavonoids
1 capsule = 1,000 mg + 200 mg citrus bioflavonoids
1 tablet = 1,000 mg + 200 mg citrus bioflavonoids
2 tablets = 1,000 mg + 400 mg citrus bioflavonoids
Prices are from our last catalog update. The final price shows at checkout.
| Formula | Form | Serving | Bioflavonoids | Calcium | Vegetarian | Bottle sizes | Per serving, from |
|---|---|---|---|---|---|---|---|
| Vitamin C 1000 mg Coated Tablets | Coated tablet | 1 × 1000 mg | 102 mg | 110 mg | Yes | 90, 120, 2 × 120 | 13¢ |
| 500 mg 24 Hour Tablets | Coated tablet | 2 × 500 mg | 204 mg | 110 mg | Yes | 90, 4 × 90 | 15¢ |
| 500 mg with Citrus Bioflavonoids Capsules | Capsule | 2 × 500 mg | 400 mg | 110 mg | No | 60, 120, 240, 300 | 19¢ |
| 1000 mg with Citrus Bioflavonoids Capsules | Capsule | 1 × 1000 mg | 200 mg | 108 mg | No | 90, 105, 3 × 90 | 21¢ |
| 1000 mg with Citrus Bioflavonoids Vegetarian Tablets | Vegetarian tablet | 1 × 1000 mg | 200 mg | 110 mg | Yes | 45, 120, 180, 2 × 180 | 17¢ |
| 500 mg with Citrus Bioflavonoids Vegetarian Tablets | Vegetarian tablet | 2 × 500 mg | 400 mg | 110 mg | Yes | 90, 450 | 16¢ |
Every serving across the Ester-C family is 1,000 mg. Compare every bottle size
No formula matches all three answers. Change one of them to see the closest match.
Vitamin C bound to calcium instead of left as an acid. That is why every serving also brings about 110 mg of calcium, 8% of the Daily Value, printed on the panel.
NIH describes Ester-C as calcium ascorbate with dehydroascorbate, calcium threonate, xylonate and lyxonate. Our panels list them as naturally occurring vitamin C metabolites.
The bottle line adds 200 to 400 mg of citrus bioflavonoids per serving, from sweet orange, tangerine, lime, lemon and acerola. The coated box line carries 102 to 204 mg of its C-Sorb complex.
In a 2006 crossover trial, people sensitive to acidic foods reported 33 mild stomach complaints after Ester-C and 55 after plain ascorbic acid.
In a 2016 trial funded by the then owner of Ester-C, vitamin C in white blood cells rose more with it at 8 and 24 hours. Blood plasma levels did not differ.
NIH, reviewing the forms, writes that research has not shown any form of vitamin C to be better than the others. Both trials above are small and short: three days of each form in one, a single dose in the other.
The full story, with the study details and the sources, is in Buffered vitamin C, explained.
From sunrise to sunset
The directions on our boxes ask adults for one serving daily, preferably with a meal. Take it with breakfast and it becomes part of the morning.
A few seconds from our day-cycle film.
One serving is about 13 times your RDA and half the upper limit of 2,000 mg a day from food and supplements together.
| Amount Per Serving | Amount | %Daily Value |
|---|---|---|
| Vitamin C(as Ester-C® Calcium Ascorbate) | 1,000 mg | 1,111% |
| Calcium(as Ester-C® Calcium Ascorbate) | 110 mg | 8% |
| C-Sorb™ Citrus Bioflavonoid Complex | 102 mg | ** |
Citrus Bioflavonoid Complex (Citrus spp.) (peel and fruit), Sweet Orange, Tangerine, Lime, Lemon, Acerola Extract, Rutin, Hesperidin Complex (Citrus spp.) (peel), Naturally Occurring Vitamin C Metabolites
**Daily Value not established.
One tablet for the 1,000 mg products, two for the 500 mg ones. The amount per serving is the same either way.
The Daily Value of vitamin C is 90 mg, so 1,000 mg prints as 1,111%. The NIH upper limit for adults is 2,000 mg a day from all sources.
The calcium comes with the calcium ascorbate. If you count calcium, add 110 mg per serving.
Citrus bioflavonoids have no Daily Value, so the panel shows two asterisks instead of a percentage.
Each family of the Ester-C range is counted once.
3 formulas
One tablet or capsule, one full serving. The 1000 mg coated tablet comes in the yellow box. The 1000 mg capsule and vegetarian tablet add 200 mg of citrus bioflavonoids.
3 formulas
Half-size pieces, two to a serving. The 24 Hour coated tablets come in the yellow box. The capsules and vegetarian tablets bring 400 mg of citrus bioflavonoids per serving.
4 formulas
The amber bottle with the orange cap. Capsules and vegetarian tablets at 500 mg and 1000 mg, each serving carrying 200 to 400 mg of citrus bioflavonoids from orange, lemon, lime and acerola.
Most adults in the United States need 75 or 90 mg of vitamin C a day, and one serving of our tablets holds 1,000 mg.
If plain vitamin C tablets leave your stomach sour, the word "buffered" on a bottle starts to matter.
Turn a bottle of Ester-C around and the black-ruled box on the back answers most questions before the first tablet.
Written by the people at Ester-C, with the NIH and FDA pages they come from.
For 37 years the Ester-C name has stood for one idea: vitamin C as calcium ascorbate, a buffered form. Today the range covers coated tablets, capsules and vegetarian tablets at two strengths.
Every bottle of the Ester-C lineup carries the full Supplement Facts on its side. More about us
Every product in the range gives you 1,000 mg of vitamin C per serving, as calcium ascorbate. On the 1000 mg products a serving is one tablet or capsule. On the 500 mg products it is two.
It is calcium ascorbate, a buffered form, and our labels call it gentle and non-acidic. In a 2006 trial of 50 people sensitive to acidic foods, fewer stomach complaints were reported after it than after ascorbic acid. NIH notes that research has not shown any form of vitamin C to be better overall, so judge by how it sits with you.
Both reach the same 1,000 mg serving. Take a 1000 mg product if you want one piece a day. Take a 500 mg product if you prefer smaller tablets or capsules, two a day. See them side by side on Compare Ester-C.
The directions on our boxes are for adults to take one serving daily, preferably with a meal. A serving is half the adult upper limit of 2,000 mg a day that NIH sets for vitamin C from all sources. Ask your doctor first if you are pregnant, nursing, take medicine or have a medical condition.
Yes. Calcium ascorbate carries calcium with it: 110 mg per serving on most panels, 108 mg on the 1000 mg capsule. That is 8% of the Daily Value, worth adding if you count your calcium.
Our tablets are labeled vegetarian or vegetarian friendly. The panels of the bottle line list gluten-free, non-GMO, soy-free, yeast-free and dairy-free. The coated boxes list no gluten, no milk, no soy and no artificial colors, flavors or sweeteners among others.
Every product page has a buy button that takes you to our retail partner, where payment, shipping and returns are handled. The prices on this site are from our last catalog update. The price at checkout is the one that counts.
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