Does Lemon Juice Clear Acne?
Some Chemicals in Lemon Juice May Help
The Essential Information
Applying lemon juice topically to acne-prone areas of the skin is a popular at-home remedy. However, scientists have not performed clinical trials to study the effect of lemon juice on acne, so how do we know if applying lemon juice to the skin will help reduce acne? To get to the bottom of this, we must rely on studies that have investigated specific chemicals that are in lemon juice, like alpha hydroxy acids (AHA).
This research suggests that certain chemicals in lemon juice as well as chemicals in lemon peel oils may have the potential to treat acne through reducing bacteria growth, skin oil production, and inflammation. However, more research will need to be performed to confirm these effects in human skin and to identify any side effects lemon juice may cause.
The Bottom Line: While it is possible that lemon juice might help reduce acne to some degree, it is unlikely that lemon juice alone will clear acne. Keep your expectations realistic, and if you are aiming for dramatic improvement in your acne, consider proven treatments instead of, or in addition to, lemon juice.
Numerous online anecdotal reports suggest that lemon juice helps reduce acne, while others report no acne-clearing benefit. Scientists have not performed any studies investigating the effect of lemon juice on acne, but studies on how individual chemicals present in lemon juice suppress the factors involved in acne help shine some light on the subject and point toward the possibility that lemon juice, and oils in lemon peels might help to some degree.
Chemical Composition of Lemons
Lemons are composed of a juice-filled pulp, a fiber-rich white area called albedo, and a peel called flavedo.
Lemon juice: Lemon juice is extracted from the pulp and consists of 60% water, 5 - 8% citric acid, and a mixture of other chemicals, including malic acid, ascorbic acid (vitamin C), glucose, and minerals like potassium and magnesium. Citric acid and malic acid are classified as alpha-hydroxy acids (AHAs), which are commonly used in skincare products for the treatment of acne.1,2 This gives us a hint that lemon juice may in fact help reduce acne in a similar way to AHAs.
Lemon peel: Most people using lemons to treat acne only use lemon juice and discard the peel. However, the lemon peel contains a high concentration of a fatty acid called linoleic acid. Acne-prone skin tends to be deficient in linoleic acid. Whether the oils from a lemon peel can be topically applied and help increase linoleic acid levels, and in turn treat acne, is still unknown.1
Potential Benefits of Lemons on Acne
Several studies investigating the effect of lemon juice and lemon peels on acne have found that chemicals in lemons may help:
- Reduce the growth of acne bacteria
- Decrease skin oil production
- Reduce inflammation
All of these could theoretically help reduce acne. Let's have a look one by one.
Reducing the growth of acne bacteria
Acne bacteria, called P. acnes, is a common bacteria that lives in the skin of people both with and without acne, but can worsen acne when it begins over-growing. Three studies have found that lemon juice itself, or certain chemicals found in lemon juice, may possess antibacterial properties, which would potentially suppress P. acnes growth.
Expand to see details of these three studies
A 2013 study published in the International Journal of Science Inventions Today found that lemon juice inhibited the growth of P. acnes. To perform this study, scientists collected pus from human acne lesions and grew the bacteria in the pus before treating it with different concentrations of lemon juice. The scientists found that all concentrations of lemon juice tested were able to inhibit the growth of P. acnes, even the lowest 20% concentration.3
A 2008 study published in the journal of Bioscience, Biotechnology, and Biochemistry found that citrus oils were able to inhibit P. acnes growth. To perform this study, the researchers obtained two citrus fruits that were not lemons, but were instead fruits common to the island on which the study was performed. They found that the two most common oils in these citrus fruits were limonene and terpinene, which also make up 88% of the oils in lemons. After isolating the oils, the researchers added them to laboratory-grown P. acnes samples and measured bacterial growth. Both oils showed properties that interfered with the P. acnes.4
A 2016 study published in the International Journal of Cosmetic Science found that a combination of zinc oxide and citric acid displayed antimicrobial activity against P. acnes. To perform this study, scientists grew P. acnes in a laboratory before treating it with different concentrations of zinc oxide and citric acid, sometimes using more zinc oxide than citric acid and vice versa. The researchers found that an equal concentration of zinc oxide and citric acid, rather than either substance alone, showed the highest antibacterial activity.5
Decreasing skin oil production
Skin oil, called sebum, is produced by glands in the skin called sebaceous glands. Acne-prone skin often produces more sebum than healthy skin. Sebum is a contributing factor to acne, and generally speaking, the more sebum a person has, the more likely he or she will develop acne. One one study has found that citrus peel components may decrease the production of sebum.
Expand to see details of study
A 2007 study published in the Journal of Investigative Dermatology found that nobiletin, a chemical found within citrus peels, decreased the amount of sebum produced in hamster skin. Additionally, application of nobiletin also decreased the size and number of the sebaceous glands.6
Acne is at its root an inflammatory disease, so anything that can reduce inflammation could hypothetically reduce acne symptoms. Furthermore, when inflammation in acne lesions does not go away in a timely manner, it can lead to acne scarring. Three studies have found that chemicals in lemons may decrease inflammation by inhibiting a variety of specific inflammatory proteins.
Expand to see details of these three studies
A 2010 literature review published in the Journal of Clinical, Cosmetic, and Investigational Dermatology reported that citric acid and ascorbic acid can prevent inflammation by inhibiting inflammatory proteins called NFkB and TNF-alpha.7
Mentioned previously, the 2007 study published in the Journal of Investigative Dermatology also found that the nobiletin found in citrus peels can suppress the release of inflammatory proteins called IL-1and IL-6.6
Also mentioned previously, the 2008 study published in Bioscience, Biotechnology, and Biochemistry found that the citrus oils limonene and terpinene reduced the secretion of TNF-alpha and another inflammatory protein called IL-8.4
How to Use Lemons for Acne:
- Very gently wash your skin with only your bare hands, using a cleanser designed for sensitive facial skin.
- Rinse thoroughly with warm (not hot) water.
- Cut a lemon in half and squeeze out the juice into a bowl. Tip: Use a citrus juicer to get all the juice out.
- (Optional) Peel the lemon and cut the peel into small pieces. Put the small pieces of the lemon peel into a garlic press and squeeze out the oils and add it to the juice in the bowl.
- Soak up the juice (and oils if you added them) with a cotton ball or cotton pad.
- Very gently apply to your skin.
- Repeat steps 4 and 5 until you have covered any areas of your skin that have acne or are prone to acne.
- Allow the juice (and oils if you added them) to dry. This should take about 5-10 minutes. Note: If your skin stings too much or you experience too much discomfort, rinse it off immediately with warm water.
- Rinse your skin with warm water and to very gently remove the lemon components from your skin. Remember: Irritation can lead to acne, so always stay extremely gentle.
- Washing your skin and applying lemon juice (and oil) will leave your skin prone to dehydration. Acne-prone skin is clearest when it is balanced. Therefore, apply a moisturizer to keep your skin balanced.
Keep your expectations realistic: Even if the alpha hydroxy acids and other chemicals in lemons and lemon peels help with acne, they likely will not help to dramatically clear the skin. Therefore, do not look for this to completely clear your skin. Expect moderate improvement only.
- Cupane, M. Effects of some practices of citrus postharvest management on fruits quality and aromatic fingerprint. (Universita Delgi Studi Di Palermo, 2015).
- Hsiao, Y. P. et al. Triggering Apoptotic Death of Human Epidermal Keratinocytes by Malic Acid: Involvement of Endoplasmic Reticulum Stress- and Mitochondria-Dependent Signaling Pathways. Toxins (Basel) 7, 81 - 96 (2015).
- Shinkafi, S. & Ndanusa, H. Antibacterial activity of citrus lemon on acne vulgaris (pimples). Int J Sci Interv Today 2, 397 - 409 (2013).
- Kim, S. S. et al. Biological activities of Korean Citrus obovoides and Citrus natsudaidai essential oils against acne-inducing bacteria. Biosci Biotechnol Biochem 72, 2507 - 13 (2008).
- Bae, J. Y. & Park, S. N. Evaluation of anti-microbial activities of ZnO , citric acid and a mixture of both against Propionibacterium acnes. Int J Cosmet Sci 1 - 8 (2016).
- Sato, T. et al. A citrus polymethoxy flavonoid, nobiletin inhibits sebum production and sebocyte proliferation, and augments sebum excretion in hamsters. J Invest Dermatol 127, 2740 - 8 (2007).
- Kornhauser, A., Coelho, S. G. & Hearing, V. J. Applications of hydroxy acids: classification, mechanisms, and photoactivity. Clin Cosmet Investig Dermatol 3, 135 - 142 (2010).