Integrative Summary

Pimples can be embarrassing for teenagers and adults alike. The modern treatment of acne requires a holistic approach.

Acne is a very common condition that involves the formation of comedones (“pimples”) in the skin. The known causes of acne in both western medicine and naturopathic medicine are summarized as the “four pillars of acne”: clogged pores, as well as increased oil, bacteria and inflammation. Interestingly, in Ayurveda the very same “pillars” are understood as imbalance of the doshas and so increased kapha and/or increased pitta together with slight increase in vata can lead to the various forms of acne. Significant overlap also exists between the four pillars and the way acne is perceived in traditional Chinese medicine (TCM) which views acne as increased qi and the end result of unbalanced diet, increased heat and invasion by external factors (bacteria, chemicals and such) as well as stasis.

Not surprisingly treatment of acne in all four disciplines can be related to at least one of the four pillars. Read more about acne in western medicine, Ayurveda, TCM and naturopathic medicine.

Symptoms

Acne is a skin disease typical of adolescence and early adulthood. Studies have estimated that greater than 90% of adolescents will develop some form of acne[1]. Acne typically affects the face and can affect the neck, chest, and the back too. There are two groups of acne lesions known as inflammatory and non-inflammatory lesions. Inflammatory lesions are red bumps, pus-filled whiteheads, and deep red lesions known as inflammatory nodules. Non-inflammatory lesions are not as red and tend to be skin-colored, such as comedones. Acne can lead to dark spots on the skin and to scarring.

Causes

Western Medicine

Acne is caused by four main factors:

  • Clogging of the pores. This is not from dirt but from overgrowth of the skin’s cells.
  • Overproduction of oil from the skin’s oil glands, known as sebaceous glands. Several things can trigger more oil production, such as hormones and genetics.
  • Overgrowth of the bacteria Propionibacterium acnes. Everyone has this bacterium on their skin, but in people with acne, this bacterium overgrows.
  • Inflammation due to activation of the immune system.

Naturopathic Medicine

Acne is the most common skin disorder in adolescents and is also the most common skin disorder seen in dermatology practice. People are most affected on the face, though the arms/shoulders, back and upper chest are often involved. Acne is summarized as four “pillars” that include:

  1. The pore: A combination of large amounts of oils and increased shedding of cells called keratinocytes cause the pores to clog. The clogged pores increase in size and lead to the formation of comedones (pimples or zits).
  2. The oil: Increased oil (also called sebum) is commonly a response of high levels of steroid hormones called androgens which are greater during puberty and are increased just before the start of the menstrual cycle.
  3. The bacteria: The clogged pores offer a perfect environment for an unhealthy overgrowth of bacteria that is normally found on the skin. The most common strain of bacteria implicated in the formation of acne lesions is called Propionibacterium acnes.
  4. The inflammation: The increase in bacteria and oils lead to inflammation in and around the clogged pore.

These four pillars combine to create what is known as acne. The severity of symptoms varies from person to person, and treatment is often dependent on the severity of those symptoms.

Ayurvedic Medicine

The imbalances seen in acne are due to:

1) Imbalanced pitta

2) Imbalanced kapha

3) Slightly imbalanced vata

Kapha is responsible for the production of oil (also known as sebum) from the oil-producing glands in the skin. Excess oil production is one of the key factors in the development of clogged pores and blackheads. These are known as comedones. Studies have shown that those who produce more oils from their skin’s sebaceous glands are more likely to have acne [2].

This is what leads to inflamed lesions such as the red bumps, the pustules (whiteheads) and the deeper red bumps known as inflammatory nodules 

Vata is responsible for how quickly the oil is made and released from the oil-producing glands. Although excess in kapha is what leads to excess oil production, vata is also important for how quickly the oil is made and released.

Some people have more inflammatory lesions on their face such as red bumps, deeper nodules, and pustules. This is known as pitta dominant acne. Other people have more of the comedones, also known as clogged pores and blackheads. This is known as kapha dominant acne. Most people have a mix of both inflammatory lesions and comedones and so most have a mix of vata and kapha characteristics to their acne also one type will typically be dominant compared to the other.

Traditional Chinese Medicine

Just as there are many different types of acne, Traditional Chinese Medicine (TCM) understands that people develop acne from different underlying causes. Chinese medicine doctors consider the appearance of the skin such as the location of the acne, the presence of white heads and black heads, inflammation, cysts, and overall health to determine the root imbalance of acne.  Heat, toxicity, dampness, qi and blood stagnation are all common causes of acne.[3,4]

  1. Lung heat acne manifests as white or black heads on the face around the cheeks, nose, and forehead, as well as the chest, and upper back. The greater the amount of inflammation, redness, papules, and pustules reflects the greater the amount of heat and toxicity.
  1. Stomach heat and dampness will cause inflamed and cystic acne around the mouth. Back acne is also reflective of stomach heat and toxicity. Oily skin and cysts are reflective of dampness. Poor digestion also is a sign of stomach disharmony.
  1. Acne that worsens around the menstrual cycle or in the middle of the cycle is a sign of Qi and Blood stagnation.
  1. Stasis and Phlegm can cause a severe and chronic form of acne whereby there is congestion in the blood vessels with widespread eruptions, nodules, or cysts.

Risk Factors

Age

Studies show that over 90% of adolescents may experience acne [1], and it is commonly seen around the time of puberty. Infants and neonates also commonly develop acne that is temporary and due to circulating hormones from the mother after birth. Acne tends to affect those that are in their teenage years and in their 20s. However, acne can sometimes last into the 30s and 40s.[5]

Environment

Hot and humid climates

Heat and humidity have been associated with breakouts of acne.[7,8]

Humid and warm weather can aggravate acne.[9] Humid weather increases kapha and warm weather increases pitta. Practices that expose the skin to heat and sweating such as high heat yoga and sweating under headbands can worsen acne as well since this can create a local environment that can aggravate kapha and pitta.

Invasion of external pathogens

This describes bacteria, chemicals from cosmetics, or extreme weather conditions that may aggravate the skin.

Hormones

Fluctuations in hormones like progesterone are thought to stimulate the oil glands to produce more oils and may account for acne that flares with menstrual periods.[10]

Hormone imbalances are a factor in acne development. In Chinese medicine this is due to Qi and Blood stagnation.

Genetics

Genetics and constitution

If your parents or siblings have had acne, there is a greater chance that you will acne as well.

Those that have a higher kapha and pitta in their base constitution have a greater risk for developing excess kapha and pitta. For example, those that naturally make more skin oils are at increased risk for the development of acne [2].

Digestion

Digestion provides a method for the body to eliminate toxins and stay healthy. Constipation, diarrhea, bloating, abdominal pain, or acid reflux can all point to imbalances in the stomach. The gut-skin connection may be from imbalances in the intestinal bacterial that affecting the skin bacteria levels leading to acne development.[6]

Lifestyle

Exercise

Exercise is commonly thought to worsen acne. However, one study found that exercising did not increase the chances of breakouts on the body acne.[11]

Diet

Several studies have shown that milk intake, specifically skim milk, and foods that have a high glycemic-index may be related to worsened acne.[12-15]

In those people that are predisposed to having acne, diet can be important. Foods that increase kapha can worsen acne. Two examples are milk and high-glycemic foods and both have been correlated with presence of acne in observational studies [16]. There are no prospective randomized studies that have assessed the role of milk or high-glycemic foods and acne.

Eating high glycemic index foods, those that are sugary and simple carbohydrates, too many dairy products, and poly unsaturated fats, has been shown to worsen acne.[17,18] In Chinese medicine eating too many sweet foods and dairy leads to the development of dampness.

Occupation

In addition, occupations requiring exposure to high heat, such as furnace workers or smelters, and occupations with exposure to petroleum-based products, cutting oils, or coal tar have increased rates of acne.[19]

Products

Products that clog pores

Products that cause the pores on the face to clog can worsen acne. Please read our section what it means to be non-comedogenic.

Products that aggravate kapha

Creams that block the skin’s pores can increase kapha in the skin and cause further formation of comedones. Some examples include thick moisturizers such as petrolatum.

Stress

Stress tends to flare acne and previous studies have shown that acne can flare during time of increased psychological stress.[20-22]

Stress and frustration cause Qi stagnation which is why periods of stress can cause a break out.

Treatments

Overview

Acne is a chronic condition that typically improves with age although it can stay persistent into the 30s and 40s. Therefore, the treatments require daily maintenance, as there is no cure for acne.

The typical treatments for acne include either topical, oral, or a treatment that combines both oral and topical treatments. Acne is not an infection but antibiotics are frequently used to help control inflammation and reduce the number of Propionibacterium acnes bacteria.

Typical strategies are to decrease kapha, decrease pitta, and keep vata from increasing.

Chinese herbal medicine focuses on correcting the underlying imbalance which is causing the acne. Contemporary research shows herbs that common treat acne may also work through antibiotic, anti-inflammatory, antioxidant, and anti-sebum properties.

Treatment of acne is typically based on the severity of acne and can vary between those with mild, moderate, or severe acne. The goal of each form of treatment against acne is generally targeted against at least one of the four pillars.

  • The pore: normalize how quickly keratinocyte skin cell divide and clog pores
  • The oil: inhibit sebum (oil) production and improve sebum quality
  • The bacteria: antibacterial control
  • The inflammation: reduce inflammation
Medications

Topical medications

  • Benzoyl peroxide: This is available in many over-the-counter preparations. It helps with unclogging pores and in reducing the amount bacteria in the lesions
  • Salicylic acid: This is available in many over-the-counter preparations. It helps with unclogging pores.
  • Sulfur based washes: This is available as a prescription and as over-the-counter preparations. It helps reduce inflammation.
  • Retinoids (such as tretinoin, adapalene, and tazarotene): These are available as prescriptions from a health care provider. Retinoids help with unclogging pores, reduce the number of bacteria, and decrease inflammation.
  • Azelaic acid: Azelaic acid is an organic substance found in some foods and is also naturally produced by yeast that reside on normal skin. Azelaic acid is commonly used as acne treatment and many different acne products contain Azelaic acid.

 

Oral/Systemic medications

  • Antibiotics: These are available as a prescription from a health care provider. They help reduce bacteria and inflammation
  • Oral contraceptives: These are available as a prescription from a health care provider. They help reduce the oil production from the skin’s oil glands.
  • Spironolactone: This is available as a prescription from a health care provider. It helps reduce the oil production from the skin’s oil glands.
  • Isotretinoin: This is available as a prescription from a health care provider. It helps unclog pores, reduce oil production from the skin’s oil glands, reduce the amount of bacteria, and reduces inflammation.</-w->
Products/Treatments

Essential oils

Several essential oils are known to reduce pitta and kapha. One example is tea tree oil that has been shown to balance all three doshas [23]. Tea tree oil preparations have been shown to improve acne [24]. Essential oils carry the risk for causing skin allergies and essential oils should be diluted in a carrier oil and then test on a small portion of the skin before they are used.

Herbs

Herbs and supplements that either decrease kapha and pitta or balance the three doshas may help reduce the presence of acne lesions. Herbs that keep kapha and pitta from increasing include turmeric and neem.

Acne from lung heat is often treated with herbs that release the exterior and clear heat from the lungs such as herbal formula Pi Pa Qing Fei Yin. [3] Niu bang zi (burdock seed) is an herb commonly used for for clearing lung heat and it has also shown an antibacterial effect on the bacteria Propionibacterium acnes the bacteria that causes acne.[25]

When the heat in the stomach is more pronounced, the formula may include huang lian (coptis rhizome) which clears heat, toxicity, and dampness from the stomach. This herbs are well known for their anti-inflammatory and has show antibacterial capabilities against p. acnes, the bacteria that causes acne.[26]

Heat toxicity is a reflection of acne inflammation. Herbal formula Wu Wei Xiao Du Yin (Five Ingredient Decoction to Eliminate Toxicity) has herbs that attack p. acnes such as zi hua di ding as well as herbs that reduce inflammation such as jin yin hua (honeysuckle) and ye ju hua (wild chrysanthemum).[26,27]

For acne that worsens with your periods, herbs to move qi and blood stagnation such as yi mu cao (Chinese motherwort), dang gui (Chinese angelica root) and dan shen (saliva miltiorrhiza) are great for moving blood and balancing hormones.

Herbs may also be used topically in creams, washes, and herbal facials. Dian Dao Shui (Upside down cream) is a classical topical formula which includes huang lian (coptis rhizome) and sulfur (liu huang).[3] Topically, huang lian and it’s active ingredient berberine, has also been shown to reduce the production of sebum that leads to the clogged pores.[25].[28] Green tea has also been shown to topically fight acne bacteria.[29]

Naturopathic approaches to herbals include the following  

  • The pore: Turmeric is one herb that has been shown to have a beneficial effect on the keratinization of cells in the pore[30]
  • The oil: The hormonal control of acne using herbs is common in naturopathic medicine. Herbs like Chaste Tree (Vitex agnus-castus)[31], Green Tea (Camellia sinensis)[32] and Saw Palmetto (Serenoa repens)[33] are known to have effects that reduce the common hormones associated with acne[34].
  • The bacteria: Herbs such as Oregon Grape (Mahonia aquifolium), Usnea (Usnea spp.), and Purple Coneflower (Echinacea angustifolia) can be helpful against the acnes bacteria of acne[35]. Other commonly used herbal remedies shown to inhibit of P. acnes include: Mangosteen (Garcinia mangostana), Hops (Humulus lupulus), Tea Tree (Melaleuca alternifolia)[36], as well as Green Tea (Camelia sinensis) and Pomegranate (Punica granatum).[29]
  • The inflammation:   The herbal control of inflammation is common with herbs such as Turmeric (Curcuma longa)[37-39], Aloe (Aloe vera), and Licorice (Glycyrrhiza glabra) are shown to have anti-inflammatory properties.[36]
Procedures

Acupuncture

Acupuncture is very common method of addressing the acne. Acupuncture may be located around the acne or throughout the body to address specific imbalance.[4] It is often combined with herbal therapies to enhance the effect of treatment. Electro acupuncture has also been shown to reduce androgen hormones which have been associated with acne.[40] Learn more about acupuncture for acne

Detoxification

Detoxification is a common practice in the naturopathic approach to skin treatment. The skin is one of the detox organs, and this happens generally through sweating. Saunas can help to increase the mobilization and release of toxins through the skin[41]. The liver is also an organ of detoxification, and most naturopathic practitioners will include liver support with treatment.

Nutrition

Diet

  • Mediterranean diet: One study found that those that eat a Mediterranean diet are less likely to have acne.[42] This study was a correlation based study and did not look at it from a primary perspective.
  • Low glycemic diet: A study in males with acne showed that a low glycemic diet improved their acne.[13]

The diet should focus on foods that do not increase kapha and pitta. Milk increase kapha and a switch to non-dairy based alternatives may be helpful. Other kapha increasing foods include fried foods and meat and both have been associated with increased presence of acne [43].On the other hand, low glycemic load diets reduce kapha. Low glycemic load diets can be helpful for reducing acne [13,24]. Mediterranean diets are known to reduce the effects of pitta and kapha with a focus on light vegetable and fruits with a low to moderate amount of dairy and food containing refined sugars. A case-control study showed that those that ate a Mediterranean diet had lower incidence of acne [42]

Diet is typically one of the first methods of acne treatment used in naturopathic medicine. The ideal diet would closely resemble a Paleolithic diet [17,44,45], which focuses on increased vegetable, fruit and fish intake, and avoidance of sugars and symptom causing foods like. Low glycemic-load diets may improve acne [13,46]. Additionally, reduction of milk and dairy intake has been correlated with improved acne[46,47].

 

Supplements

  • Zinc: Though not necessarily correlated with the formation of acne, a decreased blood level of zinc has been shown to worsen acne,[48] so the inclusion of zinc may help to reduce symptoms.
  • Vitamin B6: This vitamin has been shown to be beneficial for premenstrual acne flares,[49] but is also believed to cause acne.[50]
  • Omega-3 Fatty Acids: These healthy oils are found in many types of food, including: fish, flaxseed, borage, and eggs. Several studies show the benefits of using these healthy oils for acne.[51-54]
Lifestyle

Stress reduction

Stress aggravates vata and reduces ojas, thereby making the skin more susceptible to inflammation. While hot yoga is not recommended, other types of yoga can reduce stress and keep pitta from increasing.

Need some help comparing symptoms? Check out our Symptom Educator.

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References

  1. Stathakis V, Kilkenny M, Marks R. Descriptive epidemiology of acne vulgaris in the community. Australas J Dermatol.1997;38(3):115-123. PMID:9293656; http://www.ncbi.nlm.nih.gov/pubmed/9293656.
  2. Janiczek-Dolphin N, Cook J, Thiboutot D, et al. Can sebum reduction predict acne outcome? Br J Dermatol.2010;163(4):683-688. PMID:20518779; http://www.ncbi.nlm.nih.gov/pubmed/20518779.
  3. Xu Y. Dermatology in Traditional Chinese Medicine. United Kingdom: Donica Publishing Ltd. ; 2004.
  4. Cao HJ, Yang GY, Wang YY, et al. Acupoint Stimulation for Acne: A Systematic Review of Randomized Controlled Trials. Med Acupunct.2013;25(3):173-194. PMID:24761172; http://www.ncbi.nlm.nih.gov/pubmed/24761172.
  5. Perkins AC, Maglione J, Hillebrand GG, et al. Acne vulgaris in women: prevalence across the life span. J Womens Health (Larchmt).2012;21(2):223-230. PMID:22171979; http://www.ncbi.nlm.nih.gov/pubmed/22171979.
  6. Bowe W, Patel NB, Logan AC. Acne vulgaris, probiotics and the gut-brain-skin axis: from anecdote to translational medicine. Benef Microbes.2014;5(2):185-199. PMID:23886975; http://www.ncbi.nlm.nih.gov/pubmed/23886975.
  7. Wells JM. Tropical acne -- one hundred cases. J R Army Med Corps.1981;127(1):55-58. PMID:6453225; http://www.ncbi.nlm.nih.gov/pubmed/6453225.
  8. Sardana K, Sharma RC, Sarkar R. Seasonal variation in acne vulgaris--myth or reality. J Dermatol.2002;29(8):484-488. PMID:12227481; http://www.ncbi.nlm.nih.gov/pubmed/12227481.
  9. Lees M. Clearing Concepts: A Guide to Acne Treatment. Clifton Park, NY: Milady; 2014.
  10. Ju Q, Tao T, Hu T, et al. Sex hormones and acne. Clin Dermatol.2017;35(2):130-137. PMID:28274349; https://www.ncbi.nlm.nih.gov/pubmed/28274349.
  11. Short RW, Agredano YZ, Choi JM, et al. A single-blinded, randomized pilot study to evaluate the effect of exercise-induced sweat on truncal acne. Pediatr Dermatol.2008;25(1):126-128. PMID:18304176; http://www.ncbi.nlm.nih.gov/pubmed/18304176.
  12. Adebamowo CA, Spiegelman D, Danby FW, et al. High school dietary dairy intake and teenage acne. J Am Acad Dermatol.2005;52(2):207-214. PMID:15692464; http://www.ncbi.nlm.nih.gov/pubmed/15692464.
  13. 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(1):107-115. PMID:17616769; http://www.ncbi.nlm.nih.gov/pubmed/17616769.
  14. Smith RN, Braue A, Varigos GA, et al. The effect of a low glycemic load diet on acne vulgaris and the fatty acid composition of skin surface triglycerides. J Dermatol Sci.2008;50(1):41-52. PMID:18178063; http://www.ncbi.nlm.nih.gov/pubmed/18178063.
  15. Mahmood SN, Bowe WP. Diet and acne update: carbohydrates emerge as the main culprit. J Drugs Dermatol.2014;13(4):428-435. PMID:24719062; https://www.ncbi.nlm.nih.gov/pubmed/24719062.
  16. Bronsnick T, Murzaku EC, Rao BK. Diet in dermatology: Part I. Atopic dermatitis, acne, and nonmelanoma skin cancer. Journal of the American Academy of Dermatology.2014;71(6):1039.e1031-1039.e1012. http://www.sciencedirect.com/science/article/pii/S019096221401576X.
  17. Melnik BC. Linking diet to acne metabolomics, inflammation, and comedogenesis: an update. Clin Cosmet Investig Dermatol.2015;8:371-388. PMID:26203267; http://www.ncbi.nlm.nih.gov/pubmed/26203267.
  18. Paoli A, Grimaldi K, Toniolo L, et al. Nutrition and acne: therapeutic potential of ketogenic diets. Skin Pharmacol Physiol.2012;25(3):111-117. PMID:22327146; http://www.ncbi.nlm.nih.gov/pubmed/22327146.
  19. Bolognia J, Jorizzo JL, Schaffer JV. Dermatology. 3rd ed. London: Elsevier Health Sciences UK; 2012.
  20. Chiu A, Chon SY, Kimball AB. The response of skin disease to stress: changes in the severity of acne vulgaris as affected by examination stress. Arch Dermatol.2003;139(7):897-900. PMID:12873885; http://www.ncbi.nlm.nih.gov/pubmed/12873885.
  21. Yosipovitch G, Tang M, Dawn AG, et al. Study of psychological stress, sebum production and acne vulgaris in adolescents. Acta Derm Venereol.2007;87(2):135-139. PMID:17340019; http://www.ncbi.nlm.nih.gov/pubmed/17340019.
  22. Orion E, Wolf R. Psychologic factors in the development of facial dermatoses. Clin Dermatol.2014;32(6):763-766. PMID:25441469; https://www.ncbi.nlm.nih.gov/pubmed/25441469.
  23. Miller L, Miller B. Ayurveda & Aromatherapy: The Earth Essential Guide to Ancient Wisdom and Modern Healing. Twin Lakes, WI: Lotus Press; 1995.
  24. Cao H, Yang G, Wang Y, et al. Complementary therapies for acne vulgaris. Cochrane Database Syst Rev.2015;1:CD009436. PMID:25597924; http://www.ncbi.nlm.nih.gov/pubmed/25597924.
  25. Nam C, Kim S, Sim Y, et al. Anti-acne effects of Oriental herb extracts: a novel screening method to select anti-acne agents. Skin Pharmacol Appl Skin Physiol.2003;16(2):84-90. PMID:12637783; http://www.ncbi.nlm.nih.gov/pubmed/12637783.
  26. Muluye RA, Bian Y, Alemu PN. Anti-inflammatory and Antimicrobial Effects of Heat-Clearing Chinese Herbs: A Current Review. J Tradit Complement Med.2014;4(2):93-98. PMID:24860732; http://www.ncbi.nlm.nih.gov/pubmed/24860732.
  27. Chen HY, Lin YH, Chen YC. Identifying Chinese herbal medicine network for treating acne: Implications from a nationwide database. J Ethnopharmacol.2016;179:1-8. PMID:26721214; http://www.ncbi.nlm.nih.gov/pubmed/26721214.
  28. Seki T, Morohashi M. Effect of some alkaloids, flavonoids and triterpenoids, contents of Japanese-Chinese traditional herbal medicines, on the lipogenesis of sebaceous glands. Skin Pharmacol.1993;6(1):56-60. PMID:8489776; http://www.ncbi.nlm.nih.gov/pubmed/8489776.
  29. Li Z, Summanen PH, Downes J, et al. Antimicrobial Activity of Pomegranate and Green Tea Extract on Propionibacterium Acnes, Propionibacterium Granulosum, Staphylococcus Aureus and Staphylococcus Epidermidis. J Drugs Dermatol.2015;14(6):574-578. PMID:26091382; http://www.ncbi.nlm.nih.gov/pubmed/26091382.
  30. Saelee C, Thongrakard V, Tencomnao T. Effects of Thai medicinal herb extracts with anti-psoriatic activity on the expression on NF-kappaB signaling biomarkers in HaCaT keratinocytes. Molecules.2011;16(5):3908-3932. PMID:21555979; http://www.ncbi.nlm.nih.gov/pubmed/21555979.
  31. Hoffman D. Medical Herbalism: The Science and Practice of Herbal Medicine. Rochester, VT: Healing Arts Press; 2003.
  32. Azimi H, Fallah-Tafti M, Khakshur AA, et al. A review of phytotherapy of acne vulgaris: perspective of new pharmacological treatments. Fitoterapia.2012;83(8):1306-1317. PMID:22521501; http://www.ncbi.nlm.nih.gov/pubmed/22521501.
  33. Prager N, Bickett K, French N, et al. A randomized, double-blind, placebo-controlled trial to determine the effectiveness of botanically derived inhibitors of 5-alpha-reductase in the treatment of androgenetic alopecia. J Altern Complement Med.2002;8(2):143-152. PMID:12006122; http://www.ncbi.nlm.nih.gov/pubmed/12006122.
  34. Balunas MJ, Su B, Brueggemeier RW, et al. Natural products as aromatase inhibitors. Anticancer Agents Med Chem.2008;8(6):646-682. PMID:18690828; http://www.ncbi.nlm.nih.gov/pubmed/18690828.
  35. Buhner S. Herbal Antibiotics: Natural Alternatives for Treating Drug-Resistant Bacteria. 2nd. ed. North Adams, MA: Storey Publishing; 2012.
  36. Kanlayavattanakul M, Lourith N. Therapeutic agents and herbs in topical application for acne treatment. Int J Cosmet Sci.2011;33(4):289-297. PMID:21401650; http://www.ncbi.nlm.nih.gov/pubmed/21401650.
  37. Lalla JK, Nandedkar SY, Paranjape MH, et al. Clinical trials of ayurvedic formulations in the treatment of acne vulgaris. J Ethnopharmacol.2001;78(1):99-102. PMID:11585696; http://www.ncbi.nlm.nih.gov/pubmed/11585696.
  38. Jain A, Basal E. Inhibition of Propionibacterium acnes-induced mediators of inflammation by Indian herbs. Phytomedicine.2003;10(1):34-38. PMID:12622461; http://www.ncbi.nlm.nih.gov/pubmed/12622461.
  39. Ammon HP, Wahl MA. Pharmacology of Curcuma longa. Planta Med.1991;57(1):1-7. PMID:2062949; http://www.ncbi.nlm.nih.gov/pubmed/2062949.
  40. Jedel E, Labrie F, Oden A, et al. Impact of electro-acupuncture and physical exercise on hyperandrogenism and oligo/amenorrhea in women with polycystic ovary syndrome: a randomized controlled trial. Am J Physiol Endocrinol Metab.2011;300(1):E37-45. PMID:20943753; http://www.ncbi.nlm.nih.gov/pubmed/20943753.
  41. Crinnion W. Components of practical clinical detox programs--sauna as a therapeutic tool. Altern Ther Health Med.2007;13(2):S154-156. PMID:17405694; http://www.ncbi.nlm.nih.gov/pubmed/17405694.
  42. Skroza N, Tolino E, Semyonov L, et al. Mediterranean diet and familial dysmetabolism as factors influencing the development of acne. Scand J Public Health.2012;40(5):466-474. PMID:22833557; https://www.ncbi.nlm.nih.gov/pubmed/22833557.
  43. Jung JY, Yoon MY, Min SU, et al. The influence of dietary patterns on acne vulgaris in Koreans. Eur J Dermatol.2010;20(6):768-772. PMID:20822969; http://www.ncbi.nlm.nih.gov/pubmed/20822969.
  44. Kowalski LM, Bujko J. [Evaluation of biological and clinical potential of paleolithic diet]. Rocz Panstw Zakl Hig.2012;63(1):9-15. PMID:22642064; http://www.ncbi.nlm.nih.gov/pubmed/22642064.
  45. Silverberg NB. A brief primer on acne therapy for adolescents with skin of color. Cutis.2013;92(1):20-26. PMID:23961520; http://www.ncbi.nlm.nih.gov/pubmed/23961520.
  46. Melnik BC. Diet in acne: further evidence for the role of nutrient signalling in acne pathogenesis. Acta Derm Venereol.2012;92(3):228-231. PMID:22419445; http://www.ncbi.nlm.nih.gov/pubmed/22419445.
  47. Melnik B. Milk consumption: aggravating factor of acne and promoter of chronic diseases of Western societies. J Dtsch Dermatol Ges.2009;7(4):364-370. PMID:19243483; http://www.ncbi.nlm.nih.gov/pubmed/19243483.
  48. Rostami Mogaddam M, Safavi Ardabili N, Maleki N, et al. Correlation between the severity and type of acne lesions with serum zinc levels in patients with acne vulgaris. Biomed Res Int.2014;2014:474108. PMID:25157359; https://www.ncbi.nlm.nih.gov/pubmed/25157359.
  49. Gaby A. Nutritional Medicine. Concord, NH: Fritz Perlberg Publishing; 2011.
  50. Bolognia JL, Jorizzo JL, Schaffer JV. Dermatology. 3rd ed. London: Elsevier Health Sciences UK,; 2012.
  51. Khayef G, Young J, Burns-Whitmore B, et al. Effects of fish oil supplementation on inflammatory acne. Lipids Health Dis.2012;11:165. PMID:23206895; http://www.ncbi.nlm.nih.gov/pubmed/23206895.
  52. Bowe WP, Joshi SS, Shalita AR. Diet and acne. J Am Acad Dermatol.2010;63(1):124-141. PMID:20338665; http://www.ncbi.nlm.nih.gov/pubmed/20338665.
  53. Krishna S, Okhovat JP, Kim J, et al. Influence of omega-3 fatty acids on triglyceride levels in patients using isotretinoin. JAMA Dermatol.2015;151(1):101-102. PMID:25251777; http://www.ncbi.nlm.nih.gov/pubmed/25251777.
  54. Jung JY, Kwon HH, Hong JS, et al. Effect of dietary supplementation with omega-3 fatty acid and gamma-linolenic acid on acne vulgaris: a randomised, double-blind, controlled trial. Acta Derm Venereol.2014;94(5):521-525. PMID:24553997; https://www.ncbi.nlm.nih.gov/pubmed/24553997.