Diet and acne.
Bowe WP, Joshi SS, Shalita AR.
J Am Acad Dermatol. 2010 Jul;63(1):124-41.
It is common for dermatologists to dispell myths that acne wouldn’t be related to diet. Controversy exists in this domain due to the fact that a lot of the initial myths advocating an implication of certain diets (chocolate, sweets, fats) with acne, were refuted by a true “witch-hunt”, where all the previous existing allegations were “purged”. This has lead to many physicians to categorically deny these associations. In the last few years increased interest stemmed from the potential implication of dairy products and carbohydrates. This very interesting and comprehensive review of the literature shows associations, strong and weak with acne:
- -high glycemic diets (glycaemic)(high carbohydrate intake) may exacerbate acne as low glycemic diet patients have fewer lesions (Smith, 2007 and 2008)
- -dairy intake is weakly associated with acne (the hormonal content appears to be more relevant than the caloric content as skimmed milk is more strongly associated with acne) (link to milk and acne presentation) (Adebamowo, 2007 and 2008)
- -controversy is still present so as to their role (human data limited, only shown in vitro and in animals) (excessive intake side effects in bold text):
- -a. omega 3 fatty acids (individuals consuming fish and seafood were less likely to manifest skin lesions) (fishy aftertaste, abdominal pain, diarrhea (diarrhoea), easy bruising/ bleeding).
- -b. antioxidants (green tea (contains EGCG (epigallocatechin – 3 – gallate), Vitamin A, E, Selenium): lower levels in patients with more severe acne. EGCG: insomnia, increase urination and anxiety. Vitamin E: increased risk of bleeding, nausea and diarrhea. vitamin A (positive effect with 300000-500000IU per day of retinol). Human data but study flawed in methodology (Nausea, vomiting, headaches, dizziness, fatigue, blurred vision, bone pain, osteoporosis, itching, liver toxicity, hair loss, dry skin, increased intracranial pressure, birth defects)
- -c. zinc. Effective for inflammatory acne (Nausea, Vomiting, Diarrhea, abdominal cramps)
- -d .iodine
- -e. dietary fiber (acne improved by 30g of high fiber intake per day (13g of fiber in cereal per day) (flatulence, bloating, abdominal cramps)
That being said, the authors highlight the lack of randomized control trials, and invite such methodology to be used in further studies. We wish to add that, while associations are controversial, dermatologists must be able to address the issue without drawing any strongly positive or negative conclusions.