High Potency Vitamin C (formerly Buffered C Powder), 236 g
Size: 236 Grams
May be a fit for
- Adults seeking high-dose ascorbic acid with reduced GI irritation
- Practitioners protocols requiring buffered vitamin C powder for sensitive patients
- Individuals supporting seasonal immune function with concentrated ascorbic acid
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Thorne High Potency Vitamin C is a powdered ascorbic acid formula delivering a concentrated dose of vitamin C to support immune function, antioxidant defense, and connective tissue health. Formulated as a buffered powder, it's suited for individuals who require higher intake levels or who find standard ascorbic acid formulations hard on the digestive tract. Each serving is easy to adjust, making dose flexibility straightforward for practitioners and health-conscious adults alike.
Why It's Worth Considering: Thorne's manufacturing standards are NSF Certified for Sport and free from many common excipients, and the powder format allows precise, flexible dosing that capsules can't match.
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Our curation and trust scoring bring together manufacturing, testing, research, practitioner insight and reviews from across the web.
Our score is an editorial assessment, not a product certification or a guarantee of results.
Product details
Who it may suit
May be a fit for
- Adults seeking high-dose ascorbic acid with reduced GI irritation
- Practitioners protocols requiring buffered vitamin C powder for sensitive patients
- Individuals supporting seasonal immune function with concentrated ascorbic acid
- Those who prefer powdered vitamin C for flexible, adjustable dosing
Considerations
- History of kidney stones (oxalate type) — use buffered form
- Hemochromatosis (iron overload — C enhances iron absorption)
- G6PD deficiency at very high IV doses
- Taking blood thinners at doses above 2g/day
Compatibility & interactions
Works Well With
Take Separately From
No significant interactions identified. Always consult your healthcare provider.
What to expect over time
Plasma Saturation
Blood levels reach therapeutic range
Immune Boost
Enhanced white blood cell function
Collagen Support
Improved skin elasticity and wound healing
Antioxidant Reserve
Reduced oxidative stress markers
Based on clinical research on vitamin C supplementation. Water-soluble — excess is excreted within hours.
Compare the options
Compare Vitamin C Forms
Which form delivers the most?
| 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 | $ | $ | $$$ | $$ |
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Customer reviews, social conversations and expert insights, with every source in view.
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943 product and brand ratings and mentions across 7 sources.
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Explore the source sentiment summary
Strong enthusiasm for immune, skin, and collagen benefits, tempered by serious concerns over counterfeit Amazon products and post-PE-acquisition quality decline.
This summary includes broader brand discussion. Individual experiences are not evidence of product effectiveness.
A few useful answers.
Research & further reading
More category questions
How much vitamin C should I take daily?
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.
Is liposomal vitamin C worth the extra cost?
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.
Can I take too much vitamin C?
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.
Does vitamin C really help prevent colds?
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.
When is the best time to take vitamin C?
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.
Supplement information is provided for education and is not a substitute for personalized medical advice. Supplements are not intended to diagnose, treat, cure or prevent disease. Read the current product label before use.