Vitamin C Serum for Acne: Benefits, How to Choose One, and How to Use It

• Although there is some debate among users, topical vitamin C can be an effective treatment for acne.
• Vitamin C serum is most effective when combined with vitamin E and ferulic acid.
• When combined with certain ingredients, such as hyaluronic acid (HA), Vitamin C serums have been found to have moisturizing properties.
• Vitamin C serum is easy to apply, and can be used up to twice a day. 

Contrary to popular belief, poor diet and hygiene have not been proven to cause acne. Acne is essentially caused by blocked pores resulting from inflamed sebaceous glands, excess sebum production, an accumulation of keratin in the sebaceous glands, or bacteria trapped in hair follicles. 

Acne occurs primarily in teenagers due to hormonal changes that increase sebum production. 

A vitamin C serum can be one of the best defenses against acne. It is vitamin C’s anti-inflammatory and antioxidant properties, as well as its ability to promote wound healing, that make it an effective acne treatment.

How Do Vitamin C Serums Help Clear Up Acne?

Vitamin C serums have three main properties that help clear up acne breakouts. Each of these effects targets a different cause or symptom of acne. 

Antioxidant properties

Vitamin C’s ability to act as an anti-inflammatory allows it to both prevent the emergence of acne as well as reduce its symptoms. One study demonstrated that the development of bacteria-causing acne can be brought about by inflammation, therefore applying vitamin C to reduce skin inflammation leaves less risk for acne to occur. 

Additionally, these anti-inflammatory processes will help to reduce the visible signs of acne (redness and erythema) that may be present.

Anti-inflammatory 

Vitamin C works as an anti-inflammatory because it is an antioxidant. Oxidants are responsible for the skin inflammation that can cause acne. Oxidants are oxygen molecules that have an unpaired electron called a free radical. Because electrons prefer to be in pairs, the free electron will search for another which can damage skin in a variety of ways, including inflammation and subsequently, acne. 

Boosts collagen

Vitamin C has been proven to stimulate collagen production in the skin, which improves skin tone, and facilitates skin healing. This means that discoloration due to acne, as well as damaged skin, will be repaired faster after consistent applications of vitamin C.  

What about acne scars?

Although vitamin C cannot entirely cure acne scars, it can help to reduce the severity of new acne scars. It does so by promoting collagen production, improving skin tone, and reducing hyperpigmentation. 

There is some indication that vitamin C can reduce the visibility of old acne scars by promoting continual growth of collagen-rich skin. However, more scientific research is required to confirm this theory.

Can Vitamin C Serums Cause Acne?

No, vitamin C serums cannot cause acne.

One of the main arguments leveled against vitamin C is that it acts as a pro-oxidant. This means that instead of neutralizing free radicals, it will act as a free radical itself and begin to damage skin cells. 

This kind of free radical is called a reactive oxygen species (ROS). It contains unstable oxygen molecules (i.e oxygen with unbound electrons) that will cause oxidative stress to skin cells. Oxidation can be triggered particularly if vitamin C is put in contact with metals such as iron which are carried onto the skin by air pollution. 

Evidence shows that ROS and oxidative stress correlate strongly with acne outbreaks by inducing inflammation, and therefore, some people have claimed that topical vitamin C can cause acne.

While it is true that Vitamin C is an unstable compound, scientific evidence continually finds it to function as an antioxidant rather than a pro-oxident when applied topically to the skin. It actually neutralizes ROS and removes them from the skin, thus reducing the risk of inflammation and of acne breakouts. 

What to Look For in a Vitamin C Serum for Acne

Not all vitamin C serums are created equal. There are some guidelines to follow when choosing one in general, but when choosing one for acne consider the following:

• Vitamin C’s antioxidant properties are most effective when found in a concentration  between 8% and 20%. A higher concentration is more potent, and more appropriate for oily skin.
• Vitamin C will be more potent as an antioxidant when combined with other antioxidants such as ferulic acid and vitamin E.
• Other ingredients, such as witch hazel and aloe vera, can be combined with vitamin C to soothe the symptoms of acne-inflamed skin.  
• Vitamin C is best absorbed topically at a pH under 4, so ensure that additional ingredients are also effective at a low pH. For instance, salicylic acid (SA) is an active acne-fighting ingredient that also functions at a low pH (between 2 and 4). 
• For dry skin, use products with a lower concentration of vitamin C. One study found that an application of a 5% vitamin C cream effectively increased skin hydration. 
• Serums containing other hydrating ingredients such as HA, glycerin or dimethicone are also effective in managing dry, acne-prone skin.

The coloring of a vitamin C serum will indicate its effectiveness. The serum should appear slightly yellowish in tone, almost clear, and should not have any odor. With time, and exposure to oxygen, it will begin to show discoloration—usually dark yellow and eventually brownish orange. 

When vitamin C serum is oxidized, it loses its potency as an antioxidant and therefore loses efficacy. If you have a serum that has changed color, discard it. 

DIY vitamin C serum

Making a homemade vitamin C serum can be both simple and cost-effective. It is important to  maintain the correct concentration for best results. 

The following recipe will make a serum with a vitamin C concentration of 12.5%. This concentration is high enough to be effective and low enough to avoid irritation:

1. Combine 4 tbsp of distilled water with one-half tbsp of pure vitamin C powder
2. Pour into a brown or opaque bottle 
3. Shake until the powder has dissolved
4. Store in the fridge and discard after 2 weeks 

How to Use a Vitamin C Serum

A vitamin C serum can be applied once or twice a day—usually morning and night. Apply it after cleansing and before you apply other skin care products. 

1. Cleanse your face, ideally with a cleanser with a pH between 3 and 4, to ensure maximum absorption of the vitamin C. 
2. Place a few drops (use sparingly) on your fingers and apply the serum to your face and neck. 
3. Allow the serum to penetrate the skin before applying additional products. 
4. Follow with a moisturizer; if you are applying the serum in the morning, it is advisable to apply sunscreen.   

If you have sensitive skin, consider starting with a lower concentration of vitamin C since the acidity of vitamin C can lead to irritation.

Takeaway

Vitamin C serum offers can be effective in both treating and preventing acne by reducing inflammation, acting as an antioxidant, and improving skin tone. It also promotes wound healing, boosts collagen production, and is effective in reducing the appearance of scars.

Acne sufferers with all skin types can benefit from using vitamin C serum. Vitamin C can be combined with a variety of ingredients to boost benefits such as increased moisturization.

However, when combining with other skin care products, it is important to consider the pH of your vitamin C product. You can also make your own vitamin C serum at home using cost-effective, simple ingredients.