Gold C®, USP Grade Vitamin C by California Gold Nutrition is a straightforward, single-ingredient dietary supplement delivering 1,000 mg of vitamin C per tablet. Vitamin C is a critical water-soluble micronutrient that humans cannot synthesize endogenously, making dietary or supplemental intake essential for maintaining immune competence, connective tissue integrity, and protection against oxidative stress.
This product uses USP-grade ascorbic acid, a well-researched and bioavailable form of vitamin C. The 1,000 mg dose exceeds the Recommended Dietary Allowance (RDA) but falls within the range used in clinical trials investigating immune support and blood pressure regulation. It is particularly relevant for individuals with increased oxidative stress, suboptimal dietary intake, or during periods of acute illness.
Quick Summary
Full transparency is achieved with a single, clearly labeled ingredient at 1,000 mg per serving. No proprietary blends or hidden components.
The primary ingredient, vitamin C, is present at a clinically effective dose of 1,000 mg, supported by evidence for immune support, antioxidant effects, and blood pressure reduction. As a single-ingredient supplement with a well-researched active compound at a studied dose, efficacy is high.
Ascorbic acid is a well-absorbed form of vitamin C, especially at doses up to 1,000 mg. USP-grade quality ensures consistency and bioavailability, though liposomal or buffered forms may offer advantages for sensitive individuals.
Generally safe at this dose, but potential gastrointestinal side effects and drug interactions (e.g., warfarin, statins) require consideration. Iron overload risk in susceptible individuals is a documented concern.
Suggested: 1 serving/day to reach clinical midpoint
Why Take This Product
Key Benefits
- Potent Antioxidant Activity: At 1,000 mg/day, vitamin C significantly increases plasma antioxidant capacity and protects against oxidative damage, which is implicated in chronic disease and aging [5].
- Supports Collagen Synthesis: Vitamin C is a cofactor for enzymes involved in collagen production, essential for skin, joint, and vascular health.
- Enhances Iron Absorption: Vitamin C improves non-heme iron absorption from plant-based foods, beneficial for individuals at risk of iron deficiency.
Who Should Take This
Potential Side Effects
Ingredient Breakdown
The formulation contains only vitamin C in a high-purity, USP-grade form. As the sole ingredient and the namesake of the product, vitamin C is clearly the primary active component, delivered at a clinically relevant dose.
Primary Ingredients
Vitamin C
Antioxidant, immune support, collagen synthesis
USP-grade ascorbic acid ensures pharmaceutical-level purity and consistency. The 1,000 mg dose is within the clinical range studied for immune and cardiovascular benefits.
Vitamin C (ascorbic acid) is an essential nutrient that supports immune cell function, neutralizes free radicals, and acts as a cofactor in collagen production. At high doses, it can restore depleted levels during infection and enhance resistance to oxidative stress.
Practical Recommendations
- Optimal Timing And Use: For best absorption and tolerability, consider splitting the dose (e.g., 500 mg twice daily) if gastrointestinal discomfort occurs. Take with food to minimize stomach upset.
- Targeted Populations: Individuals under physical stress, smokers, or those with limited fruit and vegetable intake may derive the greatest benefit from supplementation.
- Monitor For Interactions: Consult a healthcare provider before combining with anticoagulants, statins, or niacin, as vitamin C may alter their effects.
Is it Safe?
While generally safe at this dose, high-dose vitamin C requires awareness of potential gastrointestinal side effects and drug-nutrient interactions. Individuals with iron overload disorders or those on certain medications should exercise caution.
Safety & Considerations
- Gastrointestinal: High doses may cause diarrhea, nausea, or abdominal cramps; reduce dose if symptoms occur.
- Iron Overload: Vitamin C enhances iron absorption; avoid in individuals with hemochromatosis or iron overload disorders.
- Drug Interaction: May interact with anticoagulants (e.g., warfarin), statins, and niacin; consult healthcare provider before use.
Reports for Similar Products
The Science
The 1,000 mg dose of vitamin C is well-supported by clinical evidence for immune support, antioxidant enhancement, and blood pressure modulation. As a single-ingredient supplement with a primary component at a studied clinical dose, Gold C® is positioned for high efficacy in its intended uses.
Vitamin C supplementation may reduce the risk and severity of pneumonia, particularly in individuals with low baseline vitamin C levels.
Regular vitamin C supplementation did not significantly reduce the incidence of respiratory tract infections overall but showed benefit in subpopulations under physical stress.
Vitamin C supplementation significantly reduced systolic blood pressure by 3.8 mmHg and diastolic by 1.5 mmHg in pooled analysis.
Vitamin C supplementation reduced systolic blood pressure by 3.0 mmHg overall, with greater effects observed in hypertensive and diabetic patients.
Vitamin C supplementation up to 1000 mg/day dose-dependently increases plasma antioxidant capacity and resistance to oxidative stress.
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