The blackheads and sometimes painful pimples that we know as acne occur most commonly during adolescence, but they may persist into later life as well. There is much we still don't understand about what causes acne. We do know that during adolescence and other times of hormonal imbalance, such as around menopause, glands in the skin increase their levels of oil secretions. A combination of naturally occurring yeast and bacteria then breaks down these secretions, causing the skin to become inflamed and the pimples to eventually rupture. In severe cases, acne can lead to permanent scars.
Conventional treatment, which usually is quite successful, consists primarily of oral or topical antibiotics, cleansing agents, and chemically modified versions of vitamin A.
Note: Do not rely on any of the natural treatments discussed in this article to treat severe acne in which scarring is a possibility.
Studies suggest that people with acne have lower-than-normal levels of zinc in their bodies.9,17,18 This fact alone does not indicate that taking zinc supplements will help acne.
Several double-blind, placebo-controlled studies have found zinc more effective than placebo but less effective than antibiotic therapy.
In one of these studies, 54 people were given either placebo or 135 mg of zinc as zinc sulfate daily. Zinc produced slight but measurable benefits.1 Similar results have been seen in other studies using 90 to 135 mg of zinc daily,2-5 although others failed to find that zinc helped.7,8
Relatively weak evidence suggests that a lower and safer dose, 30 mg daily, may also be helpful.6,19
A large double-blind trial (332 participants) compared 30 mg daily of zinc against a tetracycline-family medication often used for acne (minocycline at 100 mg daily).14 The results showed minocycline is more effective than zinc. Tetracycline taken at a dose of 250 mg daily,9 appears to be no more effective than zinc, but when taken at 500 mg daily it seems to be considerably more effective.10
Keep in mind that the dosages of zinc used in most of these studies are much higher than daily requirements, and have the potential for causing toxicity. Indeed, case reports indicate that people have made themselves extremely ill by taking zinc in hopes of treating their acne symptoms.15,16
For more information, see the full Zinc article.
Tea tree oil has antiseptic properties and has been suggested as an alternative to benzoyl peroxide for direct application to the skin. The best evidence for benefits with tea tree oil comes from a randomized, double-blind clinical trial of 60 people with mild to moderate acne.21 In this study, participants were divided into two groups and treated with placebo or 5% tea tree oil gel. Over the 45-day study period, researchers evaluated acne severity in two ways: by means of counting the total number of acne lesions (TLC) and also by rating acne severity on a standardized index (ASI). The results showed that tea tree oil gel was significantly more effective than placebo at reducing both the number of acne lesions and their severity.
For more information, including dosage and safety issues, see the full Tea Tree article.
In a double-blind trial, 76 individuals with moderately severe acne were treated with either 4% niacinamide gel or 1% clindamycin gel (a standard antibiotic treatment).13 Niacinamide proved to be just as effective as the antibiotic over an 8-week trial period. However, because this study lacked a placebo group, its results are unreliable.
Ayurvedic medicine has shown some promise for acne. One study evaluated the potential benefits of an herbal combination containing the following constituents: Aloe barbadensis, Azardirachta indica, Curcuma longa, Hemidesmus indicus, Terminalia chebula, Terminalia arjuna, and Withania somnifera.20 In this 4-week, double-blind, placebo-controlled study of 53 people with acne, combined topical and oral use of the herbal preparation significantly improved acne symptoms. Oral treatment alone was not effective.
Another controlled trial compared an extract of the Ayurvedic herb guggul against tetracycline for the treatment of acne, and found them equally effective.11 Unfortunately, the study report does not state whether this trial was double-blind, and for this reason the results are not reliable. (For information on why double-blinding matters, see Why Does This Database Rely on Double-blind Studies?)
The effect of diet on acne is unclear. One interesting, though far from definitive, study compared a low glycemic load diet against a high carbohydrate diet, and found that the low glycemic load diet reduced acne symptoms.22
Various herbs and supplements may interact adversely with drugs used to treat acne. For more information on this potential risk, see the individual drug article in the Drug Interactions section of this database.
1. Goransson K, Liden S, Odsell L. Oral zinc in acne vulgaris: a clinical and methodological study. Acta Derm Venereol. 1978;58:443-448.
2. Verma KC, Saini AS, Dhamija SK. Oral zinc sulfate therapy in acne vulgaris: a double-blind trial. Acta Derm Venereol. 1980;60:337-340.
3. Weimar VM, Puhl SC, Smith WH, et al. Zinc sulfate in acne vulgaris. Arch Dermatol. 1978;114:1776-1778.
4. Hillstrom L, Pettersson L, Hellbe L, et al. Comparison of oral treatment with zinc sulphate and placebo in acne vulgaris. Br J Dermatol. 1977;97:681-684.
5. Michaelsson G, Juhlin L, Vahlquist A. Effects of oral zinc and vitamin A in acne. Arch Dermatol. 1977;113:31-36.
6. Dreno B, Amblard P, Agache P, et al. Low doses of zinc gluconate for inflammatory acne. Acta Derm Venereol. 1989;69:541-543.
7. Weisman K, Wadskov S, Sondergaard J. Oral zinc sulphate therapy for acne vulgaris. Acta Derm Venereol. 1977;57:357-360.
8. Orris L, Shalita AR, Sibulkin D, et al. Oral zinc therapy of acne. Absorption and clinical effect. Arch Dermatol. 1978;114:1018-1020.
9. Michaelsson G, Juhlin L, Ljunghall K. A double-blind study of the effect of zinc and oxytetracycline in acne vulgaris. Br J Dermatol. 1977;97:561-566.
10. Cunliffe WJ, Burke B, Dodman B, et al. A double-blind trial of a zinc sulphate/citrate complex and tetracycline in the treatment of acne vulgaris. Br J Dermatol. 1979;101:321-325.
11. Thappa DM, Dogra J. Nodulocystic acne: oral gugulipid versus tetracycline. J Dermatol. 1994;21:729-731.
12. Bassett IB, Pannowitz DL, Barnetson RS. A comparative study of tea-tree oil versus benzoylperoxide in the treatment of acne. Med J Aust. 1990;153:455-458.
13. Shalita AR, Smith JG, Parish LC, et al. Topical nicotinamide compared with clindamycin gel in the treatment of inflammatory acne vulgaris. Int J Dermatol. 1995;34:434-437.
14. Dreno B, Moyse D, Alirezai M, et al. Multicenter randomized comparative double-blind controlled clinical trial of the safety and efficacy of zinc gluconate versus minocycline hydrochloride in the treatment of inflammatory acne vulgaris. Dermatology. 2001;203:135-140.
15. Igic PG, Lee E, Harper W, et al. Toxic effects associated with consumption of zinc. Mayo Clin Proc. 2002;77:713-716
16. Porea TJ, Belmont JW, Mahoney DH Jr. Zinc-induced anemia and neutropenia in an adolescent. J Pediatr. 2000;136:688-690.
17. Pohit J, Saha KC, Pal B. Zinc status of acne vulgaris patients. J Appl Nutr. 1985;37:18-25.
18. Amer M, Bahgat MR, Tosson Z, et al. Serum zinc in acne vulgaris. Int J Dermatol. 1982;21:481-484.
19. Meynadier J. Efficacy and safety study of two zinc gluconate regimens in the treatment of inflammatory acne. Eur J Dermatol. 2000;10:269 273.
20. Lalla JK, Nandedkar SY, Paranjape MH, et al. Clinical trials of ayurvedic formulations in the treatment of acne vulgaris. J Ethnopharmacol. 2001;78:99-102.
21. Enshaieh S, Jooya A, Siadat AH, et al. The efficacy of 5% topical tea tree oil gel in mild to moderate acne vulgaris: a randomized, double-blind placebo-controlled study. Indian J Dermatol Venereol Leprol. 2007;73:22-5.
22. Smith RN, Mann NJ, Braue A, et al. A low-glycemic-load diet improves symptoms in acne vulgaris patients: a randomized controlled trial. Am J Clin Nutr. 2007;86:107-15.
Last reviewed July 2012 by EBSCO CAM Review Board
Last Updated: 7/25/2012