Vitamin C: What It Does

Vitamin C is perhaps the most well-known vitamin, yet many people underestimate just how many roles it plays in the body. Vitamin C contributes to the normal function of the immune system, collagen production, iron absorption, and antioxidant defence.

Vitamin C supports multiple aspects of immune function. Vitamin C contributes to the normal function of the immune system and to the protection of cells from oxidative stress.

Vitamin C contributes to normal collagen formation for the normal function of blood vessels, bones, cartilage, gums, skin and teeth.

Vitamin C significantly enhances the absorption of non-haem iron (the type found in plant foods). Vitamin C increases iron absorption.

As a water-soluble antioxidant, vitamin C neutralises free radicals throughout the body. It also regenerates vitamin E (a fat-soluble antioxidant), creating a complementary antioxidant network. This dual action helps protect cells, DNA, and lipids from oxidative damage.

The NHS says adults need 40 mg of vitamin C a day and should be able to get it from their diet. Since vitamin C is water-soluble, excess is simply excreted — though very high doses (over 2000 mg) may cause digestive discomfort.

Vitamin C supplements come in many forms, each with different characteristics:

• Ascorbic acid: The standard form, well-absorbed and effective. Can be acidic on sensitive stomachs at high doses.
• Sodium ascorbate or calcium ascorbate: Buffered forms that are gentler on the stomach. Ideal for those who experience digestive discomfort with regular vitamin C.
• More expensive but may be worth it for those seeking maximum absorption.
• Vitamin C with bioflavonoids: Citrus bioflavonoids are found with vitamin C in fruit. A good quality supplement often includes these.
• Time-release formulations: Since vitamin C is water-soluble and excess is quickly excreted, time-release formulas provide a more sustained supply throughout the day.

Take as directed on the label.

While everyone needs vitamin C, supplementation is particularly valuable for:

• Athletes and active individuals — intense exercise increases oxidative stress and vitamin C requirements
• Vitamin C contributes to normal collagen formation for the normal function of skin.
• Older adults with limited fruit and vegetable intake

Split your daily dose into 2–3 smaller doses throughout the day rather than one large dose, as your body can only absorb a limited amount at once. Take vitamin C with meals to reduce any potential stomach irritation. Vitamin C increases iron absorption. Store vitamin C supplements in a cool, dry place away from direct light, as it degrades with heat and moisture. Complement your supplement with vitamin C-rich foods: kiwi (more per gram than oranges), bell peppers, strawberries, broccoli, and Brussels sprouts.

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This article is for informational purposes only and does not constitute medical advice. Vitadefence supplements are food supplements, not medicines. Consult a healthcare professional if you are pregnant, breastfeeding, on medication, or have a medical condition.