Reviews are largely off-topic; counterfeit concerns on Amazon and general supplement skepticism temper sentiment around NOW Foods products.
NOW Foods C-500 Calcium Ascorbate-C delivers 500 mg of vitamin C in a buffered, mineral-bound form that supports immune function, collagen synthesis, and antioxidant activity. Unlike standard ascorbic acid, calcium ascorbate is pH-neutral, making it a practical option for those with sensitive stomachs who still want consistent vitamin C intake.
Why It's Worth Considering: The buffered calcium ascorbate form reduces gastrointestinal discomfort commonly associated with acidic vitamin C supplements, while also contributing a modest amount of dietary calcium per serving.
| Feature | Ascorbic Acid | Buffered (Ascorbate) | Liposomal | Ester-C |
|---|---|---|---|---|
| Bioavailability | Good (standard) | Good (gentler) | Excellent (2-3x) | Good |
| GI Tolerance | May cause acidity | Very gentle | Excellent | Gentle |
| Best For | Budget, general use | Sensitive stomachs | Maximum absorption | Sustained release |
| Price | $ | $ | $$$ | $$ |
For maintenance, 500-1000mg daily is sufficient. For immune support during illness, 2000-4000mg in divided doses. The body can only absorb ~200-500mg at once, so split large doses throughout the day. Liposomal forms bypass this limit with 2-3x better absorption.
For most people, standard ascorbic acid at 500-1000mg is sufficient. Liposomal vitamin C is worth the premium if you need higher therapeutic doses (2000mg+) without GI distress, or if you have absorption issues. Studies show liposomal C achieves 2-3x higher blood levels than standard forms.
Vitamin C is water-soluble and excess is excreted in urine. The main risk of high doses (3000mg+) is GI distress (diarrhea, cramping) and increased oxalate production, which may contribute to kidney stones in susceptible individuals. The 'bowel tolerance' test — increasing dose until loose stools, then backing off — is a common practitioner approach.
Meta-analyses show regular vitamin C supplementation reduces cold duration by 8% in adults and 14% in children, and reduces severity. It does NOT prevent colds in most people, but it does in those under physical stress (athletes, military). Taking vitamin C after cold symptoms start has minimal benefit — daily prevention is key.
Take with food to reduce potential stomach acidity. Morning dosing is common since vitamin C may mildly increase alertness. If taking large doses (1000mg+), split into 2-3 doses throughout the day for better absorption and sustained blood levels.
† These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
