Endur-C SR 500mg
Sale

Endur-C SR 500mg

ENDUR-C® Vitamin C with Rose Hips is a sustained-release dietary supplement featuring high-potency vitamin C in a SmartMatrix™ sustained-release tablet that releases vitamin C over 5 to 7 hours to promote vascular health & antioxidant defense.*

  • Easy-to-swallow tablets 
  • No salt, sugar, starch, preservatives, artificial colors or flavorings
  • Gluten-free
  • Vegan/Vegetarian
  • Free of common allergens (milk, egg, fish, shellfish, tree nuts, peanuts, wheat and soy)
  • Sustained release (5-7 hours)

SmartMatrix is a trademark of Innovite, Inc.

Learn More
Product Info Sheet: Download Here
Clinical-Strength Formulation
SmartMatrix™ Sustained-Release
U.S. Manufactured, cGMP Certified

ENDUR - C® Vitamin C with Rose Hips is specially formulated with SmartMatrix ™ sustained-release tablet technology to releases vitamin C over 5 to 7 hours. By releasing small amounts of vitamin C as the tablet travels through the intestine, ENDUR-C allows the body to slowly absorb vitamin C. In this way, it not only helps maintain optimal blood and tissue levels, but avoids excess loss in the urine that is typical of immediate-release delivery forms of high-dose vitamin C.*

Vitamin C’s dual metabolic actions—as a biological antioxidant and as an enzyme cofactor—help protect cells from oxidative damage, support collagen and neurotransmitter synthesis, help fortify immune function, and promote iron absorption, all of which are essential for overall health (1).

Suggested Use: Take one (1) tablet daily, preferably with a meal, or as directed by your healthcare provider.

Clean Formulas

No Preservatives

Gluten-free

Vegan Options

No Artificial Flavors

By functioning as both a biological antioxidant and an enzyme cofactor, vitamin C helps defend against oxidative damage, supports tissue repair and neurotransmitter synthesis, helps fortify immune function, and aids in iron uptake, all actions that promote overall health, vitality, and well-being (1).

  • Antioxidant Defense. Vitamin C acts as a major water-soluble antioxidant, neutralizing reactive oxygen and nitrogen species and protecting biomolecules. Vitamin C helps keep metals like iron and copper in their reduced, active forms, supporting redox reactions and enzyme function. Vitamin C reduces dietary nonheme iron (Fe3+) to the more absorbable ferrous form (Fe2+), aiding absorption.
  • Enzyme Cofactor. Vitamin C is required for the amidation of certain peptide hormones, enabling their full biological activity. Vitamin C is essential for hydroxylation reactions that stabilize collagen, supporting connective tissue and skin integrity.
  • Cardiometabolic Health. Emerging research suggests the potential of supplemental vitamin C to support blood pressure health, cardiovascular health, and glucose balance, with typical dosages in the range of 500-1,000 mg/day (2-4).

Vitamin C pharmacokinetics is well understood. It’s efficiently absorbed up to 200 mg, then absorption drops to well below 50% for amounts over 1 gram with the excess excreted in urine (5). This is a key reason why Endur-C® Vitamin C with Rose Hips features sustained-release tablets. The slow, steady nutrient release aligns with the body’s natural saturation kinetics to promote optimal absorption and tissue retention (and less waste).

Other Ingredients: Vegetable wax (rice bran and/or carnauba), stearic acid(vegetable), magnesium stearate (vegetable), and silica.

ENDUR-C® Vitamin C with Rose Hips is manufactured in the United States (Oregon) in a state-of-the-art, FDA-registered facility that meets or exceeds current Good Manufacturing Practices (cGMP). Quality control tests are performed at every stage of the manufacturing process from rigorous raw material testing to finished product testing.

Precautions

Consult your healthcare professional prior to use if you have or suspect a medical condition, are taking any medications, or are pregnant or nursing.

References

  1. Combs GF Jr, McClung JP. Vitamin C. In: Combs GF Jr, McClung JP, eds. The Vitamins: Fundamental Aspects in Nutrition and Health. 6th ed. Elsevier; 2022:271-310.
  2. Guan Y, et al. Medicine (Baltimore). 2020;99(8):e19274.
  3. Xu Y, et al. Antioxidants (Basel). 2025;14(5):506.
  4. Nosratabadi S, et al. Diabetes Metab Syndr. 2023;17(8):102824.
  5. Levine M, et al. Proc Natl Acad Sci U S A. 1996;93(8):3704-3709.

Free Shipping

on all order over $99

Free Returns

within 30 days of purchase

Sustained Release

over 5–7 hours for lasting effect.