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Superior C -  500 mg - Threonic Acid - Enhanced Buffered Bioavailable Vitamin C - 90 Veg Capsules
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Superior C - 500 mg - Threonic Acid - Enhanced Buffered Bioavailable Vitamin C - 90 Veg Capsules

LifeSource Vitamins
4 Reviews
$

Superior C Tests & Uploads BETTER than Ester-C*

  • Enhanced cellular vitamin C uptake with L-threonic acid*
  • Antioxidant regeneration support with ALA (vitamins C and E and glutathione)*
  • Buffered, non-acidic formula for gentler digestion*
  • Immune function and oxidative stress support*
  • Collagen support for skin, blood vessels, and connective tissue*
  • Helps enhance non-heme iron absorption with meals*
  • May modestly reduce common cold duration and severity with routine use*
  • Includes citrus bioflavonoids for synergy*
  • Not from China*
  • Third party lab tested for purity, potency, and accuracy

Read Below: Full Description, Clinical Studies & Research on Superior C
Product Code: VITC003

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Vitamin C — Superior C — 500 mg — Vegetarian Capsules — Supports Immune Health & Antioxidant Protection*

LifeSource Vitamins Vitamin C — Superior C (500 mg) combines premium ascorbic acid with threonic acid, alpha lipoic acid, and citrus bioflavonoids in an easy vegetarian capsule to support immune function, antioxidant protection, collagen synthesis, iron absorption, and overall cardiovascular wellness. Produced in FDA-registered, GMP-certified facilities and 3rd-party tested for identity, potency & purity.*

Research Promise: At LifeSource Vitamins, our commitment is rooted in research and results. Every benefit below is supported by human clinical studies indexed in the National Institutes of Health (NIH) via PubMed, with full texts available in the National Library of Medicine (NLM) PubMed Central (PMC) when available. In addition, we reference reviews from 39 leading health organizations and insights from 20 top global universities to ensure our guidance aligns with credible science.*
Clinically Studied Benefits (with research)

Immune support — Vitamin C supports multiple immune mechanisms (barrier integrity, leukocyte function) and helps shorten common-cold duration in regular users. (NIH/PMC — Carr & Maggini, Nutrients 2017)

Common-cold duration (adjunct) — Human RCT syntheses show regular vitamin C supplementation reduces cold duration and severity in various populations. (NIH/PMC — Hemilä, Nutrients 2017)

Antioxidant protection — Vitamin C scavenges reactive oxygen species and regenerates other antioxidants in humans, lowering oxidative stress markers. (NIH/PMC — Carr & Maggini, 2017)

Collagen formation & skin — Vitamin C is essential for collagen hydroxylation; human data link adequate intake with improved dermal matrix and wound outcomes. (NIH/PMC — Carr & Maggini, 2017)

Iron absorption — Vitamin C enhances non-heme iron uptake in humans by reducing ferric to ferrous iron and forming absorbable complexes. (NIH/PMC — Lane & Richardson, 2014)

Endothelial & cardiometabolic markers — Clinical evidence shows vitamin C can improve endothelial-dependent vasodilation and select cardiometabolic risk markers. (NIH/PMC — Carr & Maggini, 2017)

Blood pressure (adjunct) — Meta-analytic clinical data indicate vitamin C supplementation can modestly reduce blood pressure, particularly in hypertensive adults. (NIH/PMC — Juraschek et al., 2012)

Wound healing support — Human clinical literature associates adequate vitamin C status with improved tissue repair dynamics and ulcer outcomes. (NIH/PMC — Carr & Maggini, 2017)

Additional Studies Showing Promising Benefits*

Vitamin C + citrus bioflavonoids — Human and mechanistic data suggest bioflavonoids may complement antioxidant networks and microvascular skin support; direct absorption synergy remains mixed. (NIH/PMC — Kaulmann & Bohn, 2016)

Threonic acid (vitamin C metabolite)mechanistic and preliminary evidence suggests it may influence vitamin C handling; robust human RCTs confirming superior uptake are limited. (NIH/PMC — Hemilä, 2017)

Alpha lipoic acid — Functions in the human antioxidant network and may help recycle vitamin C; high-quality human co-supplementation trials remain limited for firm synergy claims. (NIH/PMC — Shay et al., 2009)

Skin/photodamage (adjunct) — Oral vitamin C–containing regimens have shown signals for dermal/UV endpoints; heterogeneity and combination formulas temper certainty. (NIH/PMC — Cosmeceuticals Review, 2013)

Global Evidence & Authoritative Reviews*

NIH ODS Fact Sheet — Clinical overview of vitamin C intake, safety, deficiency, and research. (NIH ODS)

Harvard T.H. Chan School — Evidence summary on vitamin C and health outcomes. (Harvard Nutrition Source)

We monitor research from the world’s leading institutions — including Harvard, Johns Hopkins, Mayo Clinic, Cleveland Clinic, Cambridge University, Oxford, Stanford, Yale, MIT, the University of Florida, Oregon State University – Linus Pauling Institute, Tufts, Boston University, Cornell, Columbia, and Ohio State — to ensure our guidance remains aligned with the highest standards of credible science.*
Brief Benefit Bullets

• Daily immune support & shorter common-cold duration (regular users)*

• Potent antioxidant protection; supports healthy oxidative balance*

• Essential for collagen — skin, blood vessels & connective tissues*

• Aids non-heme iron absorption for energy support*

• Supports endothelial function & healthy blood-pressure markers*

• Vegetarian capsules; enhanced formula with bioflavonoids*

3rd-party lab tested for purity & potency

Suggested Use: Take 1 capsule daily with a meal, or as directed by your healthcare professional. Do not exceed recommended dose. If pregnant, nursing, taking medications, or have a medical condition, consult your physician.*

Product Specifications

• Serving Size — 1 vegetarian capsule

• Servings Per Container — 90

• Actives — Vitamin C (Ascorbic Acid) 500 mg; Threonic Acid; Alpha Lipoic Acid; Citrus Bioflavonoids

• Form — Vegetarian capsules

• Free From — Non-GMO, gluten-free, vegan; not from China*

• Quality — Third-party tested for identity, potency & purity

Perfect For

• Adults seeking enhanced immune & antioxidant support*

• Individuals with low dietary vitamin C intake*

• Those aiming for skin, heart, and iron-absorption support*

Key Ingredients

Vitamin C (Ascorbic Acid) — immune support, antioxidant protection, collagen formation, and iron absorption.* (NIH/PMC — Nutrients 2017)

Threonic Acid — vitamin C metabolite included for potential handling/uptake support (emerging human evidence).* (NIH/PMC — Hemilä, 2017 (context))

Alpha Lipoic Acid — part of the antioxidant network; may help recycle vitamin C (human evidence mixed).* (NIH/PMC — Shay et al., 2009)

Citrus Bioflavonoids — plant polyphenols that complement antioxidant defenses and microvascular support.* (NIH/PMC — Kaulmann & Bohn, 2016)

3rd-Party Testing: Every batch is verified by independent labs for identity, potency, and purity. Click here to see our 3rd-party testing.

LifeSource Vitamins — Proudly American — Since 1992

*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.

Vitamin C — Superior C 500 mg vegetarian capsules with bioflavonoids, ALA & threonic acid for immune, antioxidant, collagen & iron-absorption support. Clinically Studied Ingredients — NIH/PubMed!*


Superior C - 500 mg - Threonic Acid - Enhanced Buffered Bioavailable Vitamin C - 90 Veg Capsules

$19.99
  • Click Here to See our 3rd Party Testing On Every Single Nutrient and Every Product Sold at Lifesource Vitamins.

    *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 taking any supplements. Individual results may vary. This information is not intended to replace your healthcare provider but to support and enhance that relationship. You are encouraged to do your own research and take an active role in your health decisions. If you are pregnant, nursing, taking medications, or have any medical conditions, consult your healthcare professional before using any supplements discussed on this site.

Reviews

Average Rating:
( 4 )
Dr. L***
August 20, 2025
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Dr. L*** from n/a
August 21, 2024
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Nancy*** from n/a
January 9, 2023
A little more information, please.
The size of the zinc lozenges would be helpful to make a decision whether to order them or not.
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Stefa*** from n/a
November 27, 2022
Shopping.
Love the discounts and products. Especially the All Natural Antibiotics. I haven't been sick in over 5 years.
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