Vitamin C
What is Vitamin C?
Vitamin C, or ascorbic acid, is a water-soluble vitamin. This means that it dissolves in water and is delivered to the body’s tissues but is not well stored, so it must be taken daily through food or supplements.
Vitamin C plays a role in controlling infections and healing wounds, and is a powerful antioxidant that can neutralize harmful free radicals. It is needed to make collagen, a fibrous protein in connective tissue that is weaved throughout various systems in the body: nervous, immune, bone, cartilage, blood, and others. The vitamin helps make several hormones and chemical messengers used in the brain and nerves4.
Vitamin C consumption plays a variety of different roles in the body, including:
- Improving fertility
- Helping the body make collagen
- Supporting wound healing
- Helping the body absorb iron from plant-based foods
- Supporting the immune system
- Protecting cells from free radicals, which helps prevent disease
- Preventing deficiency-related health problems, like scurvy
Types of Vitamin C:
- Ascorbic acidis the form of vitamin C found naturally in food. It has good bioavailability but some people find it too acidic on their gut and can’t tolerate higher doses.
- Mineral ascorbatessuch as calcium and magnesium ascorbate are often called ‘buffered’ vitamin C. Many people find these to be gentler forms of vitamin C that are better tolerated by the gut. It is important however to consider the accompanying dose of mineral (calcium, magnesium etc.) when taking higher levels
When taken over long periods of time, high doses of vitamin C can increase the risk of kidney stones, particularly in people with a history of oxalate stones.
However, high doses of buffered vitamin C may not influence oxalate levels, which means that buffered vitamin C has less of a chance of producing kidney stones.
The most popular mineral ascorbates of vitamin C are sodium ascorbate, which contains 111 milligrams of sodium, and calcium ascorbate, which contains between 90 and 110 milligrams of calcium.
Why do we need extra vitamin C?
“An inadequate vitamin C intake is already more widespread than many people realize.”3. Humans are in a small minority of mammals that can’t produce their own vitamin C; it’s also water soluble and can’t be stored in the body. This means it must be regularly supplied by the diet.1 Severe deficiency leading to scurvy is rare in the developed world,2 but there are times when our daily needs for vitamin C are likely to increase, such as pollution exposure and during times of chronic stress, illness and infection.3
Your body uses extra vitamin C during times of increased need such as illness or infection so unless extra care is taken to increase dietary intake during these times, daily supplies are likely to fall short. This is when supplemental vitamin C may be a useful addition to your diet.
References:
1. Frei B., Birlouez-Aragon I., Lykkesfeldt J. Authors’ perspective: What is the optimum intake of vitamin C in humans? Crit. Rev. Food Sci. Nutr. 2012; 52: 815 – 829
2. Na IS, Nguyen K et al. Now you C me: a case of scurvy presenting as depression and anaemia. BMJ Case Rep. 2020 Mar 4; 13(3)
3. Gombart AF, Pierre A et al. A review of micronutrients and the immune system – Working in harmony to reduce the risk of infection. Nutrients 2020 Jan; 12(1): 236
- Institute of Medicine (US) Panel on Dietary Antioxidants and Related Compounds. Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids. Washington (DC): National Academies Press (US); 2000.
- https://www.hsph.harvard.edu/nutritionsource/vitamin-c/