Home / Ingredient Directory / Vitamin C
Yannis Lopez
Reviewed by Yannis Lopez · Nutrition Industry Veteran
Last updated: July 8, 2026
Immunity & Antioxidant Essential Vitamin

Vitamin C

Immune & antioxidant support

Water-soluble antioxidant
Essential for collagen

FDA Disclaimer: 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. Always consult your physician before starting any supplement.

Featured in: The Skin & Hair Stack
Overview

Vitamin C (ascorbic acid) is an essential water-soluble vitamin and one of the most well-known antioxidants. It plays a critical role in immune function, collagen synthesis, iron absorption, and protecting cells from oxidative stress.

Unlike most animals, humans cannot synthesize vitamin C, so we must obtain it from diet or supplements. It is one of the most commonly supplemented vitamins, especially during cold and flu season.

Potential Benefits

Immune Support

Supports healthy immune function. Research suggests vitamin C may reduce the duration and severity of common colds in some people.

Antioxidant Protection

Neutralizes free radicals and helps regenerate other antioxidants like vitamin E. Protects cells from oxidative damage.

Collagen Synthesis

Essential for the production of collagen, which supports skin, joints, blood vessels, and wound healing.

Generally Well Tolerated

Vitamin C is very safe. Excess is excreted in urine. Some people may experience loose stools at very high doses.

Typical Dosage
Daily Maintenance
500–1,000mg
Split into 2–3 doses for better absorption
During Illness
1,000–2,000mg daily
Many people increase dosage when feeling under the weather
Pro Tips
  • Split doses throughout the day for better absorption
  • Take with meals to reduce stomach upset
  • Works well with Zinc and Quercetin
  • Liposomal or buffered forms are gentler on the stomach
Research Snapshot

Decades of research support vitamin C's role in immune function and antioxidant protection. Meta-analyses show it may reduce cold duration by 8–14% in the general population and more in athletes under heavy physical stress.

How Vitamin C Compares

Ingredient Best For Key Difference
Vitamin C Immune support, Antioxidant, Collagen Water-soluble; excess is excreted
Zinc Immune defense, Wound healing Trace mineral; important for hormone health
Vitamin D3 Immunity, Bones, Mood Fat-soluble; needs sunlight or supplementation

Vitamin C pairs extremely well with Zinc and Quercetin for immune support.

Popular Stacks with Vitamin C
Immunity Stack
Vitamin C + Zinc + Quercetin
Most popular daily immune support
Antioxidant Stack
Vitamin C + NAC + Alpha Lipoic Acid
Great for comprehensive antioxidant support
Collagen Support Stack
Popular for skin and joint health
Eye Health Stack
Vitamin C + Lutein + Zinc
Mirrors the nutrient combination used in major eye health trials like AREDS2

Full stack recommendations coming soon in our Stacks section.

Frequently Asked Questions
How much vitamin C should I take daily?
The RDA is 75–90mg for adults, but many experts recommend 500–1,000mg daily for optimal health. During illness, some people take 1,000–2,000mg or more.
Can I take too much vitamin C?
Vitamin C is water-soluble, so excess is excreted in urine. Very high doses (above 2,000–3,000mg) may cause loose stools or stomach upset in some people.
Is vitamin C from food enough?
Many people get enough from diet (citrus, berries, peppers, broccoli), but supplementation provides higher doses that may offer additional benefits during stress or illness.
Sources & References
  1. Hemilä H, Chalker E. Vitamin C for Preventing and Treating the Common Cold. Cochrane Database Syst Rev. 2013;(1):CD000980.
  2. Carr AC, Maggini S. Vitamin C and Immune Function. Nutrients. 2017;9(11):1211.
  3. Pullar JM, et al. The Roles of Vitamin C in Skin Health. Nutrients. 2017;9(8):866.
Related Ingredients
Zinc Quercetin Vitamin D3 Elderberry
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