Topical vitamin C

Author: Vanessa Ngan, Staff Writer, 2002.


What is topical vitamin C?

Topical vitamin C or ascorbic acid is a popular vitamin being added to skin care products. Currently there are many advertising claims of topical formulation containing antioxidants that will protect against and reverse aging. However, the truth is that many of the available formulations contain very low concentrations of antioxidants that are not well absorbed by the skin. Vitamin C on the other hand, is an antioxidant, which when manufactured into a stable topical formulation, is proven to be effective in protecting against photoaging of the skin.

How does topical vitamin C work?

To understand how topical vitamin C works an understanding of the relationship between free radicals and antioxidants in the body is necessary.

  • Free radicals are molecules created as a by-product of oxygen metabolism as our bodies create energy at the cellular level. Basically, the oxygen molecule loses one electron, turning it into a free radical.
  • Free radical formation can also be augmented by external factors such as pollutants, sunlight, radiation, emotional stress, smoking, excessive alcohol, infection, and some drugs.
  • Free radicals float around the body looking for electrons to rebalance themselves. If necessary, free radicals steal electrons from normal healthy cells, this being the cause of various conditions ranging from accelerated ageing to deadly cancers.
  • Antioxidants protect healthy cells by donating an electron to the free radicals. The body produces antioxidants naturally and we can also get them from the foods we eat and from supplements.

Topical vitamin C has shown to protect the skin from UV damage caused by prolonged sun exposure by reducing the amount of free radical formation and/or sunburn cells. Exposure to UV light has also shown to decrease the naturally occurring vitamin C levels in the skin, thus topical application of vitamin C restores these photoprotectant levels. Other studies also suggest that vitamin C may play a part in the collagen biosynthetic pathway by activating collagen metabolism and dermal synthesis of elastic fibres.

What is topical vitamin C used for?

Studies have shown the following benefits of using topical vitamin C preparations.

  • Improve skin appearance by reducing fine lines and wrinkles.
  • Wound healing as it aids in stabilising collagen.
  • Protects against or lessens the severity of sunburns.

Who should use topical vitamin C?

Everyone will benefit from maintaining adequate vitamin C levels. For most people this can be achieved by eating more than 5 servings of fruit, vegetables and juices daily. There are many topical vitamin C preparations available that claim to benefit photoaged skin. However, almost all of these claims have no rigorous scientific testing to back them.

A correctly formulated topical vitamin C preparation is a difficult and costly process. Many formulations on the market are manufactured cheaply and are basically ineffective. The problems lies in the fact that vitamin C is most commonly found in the form L-ascorbic acid. This is highly unstable when exposed to oxygen, making it become useless. In addition, many of the currently available topical vitamin C preparations do not penetrate the skin sufficiently to make any difference. Research is currently underway to optimize a stable and effective topical vitamin C formulation.

If you are considering using a topical vitamin C preparation you should consult your pharmacist, doctor or dermatologist before starting, particularly if you are already using other vitamin supplements. They can help you determine which vitamins and in which form will be the most effective for you.

The treatment and prevention of scurvy, which is due to dietary vitamin C deficiency, requires oral replacement of ascorbic acid.

New Zealand approved datasheets are the official source of information for these prescription medicines, including approved uses and risk information. Check the individual New Zealand datasheet on the Medsafe website.

 

Related Information

On DermNet NZ:

Other websites:

Books about skin diseases:

See the DermNet NZ bookstore