- Many dermatologists and nutritionists wish to understand the link between diet, nutrition and dermatological health.
- A review that includes 150 studies found that few rigorous randomized controlled trials have examined these potential links.
- The authors conclude that despite the different levels of association, diet and nutrition, with a few exceptions, do not modify dermatological conditions.
There is considerable interest in the relationship between diet, nutrition and skin conditions. New research evaluates the existing research literature.
The review reports that much of the evidence supporting such relationships is based simply on associations or laboratory studies rather than randomized controlled trials, which are the gold standard for medical research.
The study is the work of lead author Dr Kabir Sardana and lead investigator Dr Soumya Sachdeva, both affiliated with the Atal Bihari Vajpayee Institute of Medical Sciences and Dr Ram Manohar Hospital Lohia in Delhi, India.
âWhile it is plausible,â the authors write, âthat certain nutritional supplements may help, they may not transcend research settings to real-life clinical scenarios. Apart from the role of gluten in celiac disease, very few dietary factors have been irrevocably linked to the disease in dermatology.
After reviewing 150 published articles on diet, nutrition and dermatology over the past 15 years, they report that “the data is not strong and leaves the dermatologist in a dilemma and the patient confused.”
It is unfortunate, say the authors, because “[a] a good knowledge of the role of nutritional supplements in dermatological diseases can be a useful tool in counseling patients and in some cases ameliorating the disorder.
The notice appears in
âThere have been interesting studies on the role of diet and / or specific supplements in acne, atopic dermatitis, psoriasis, vitiligo, [and]
“And while every study may not meet the most rigorous study design criteria,” she continued, “the information gleaned from these studies may still be of use to dermatologists.”
Regarding the lack of randomized controlled trials, Dr Farris explained:
âIt’s important to remember that most large randomized, placebo-controlled studies are funded by manufacturers or pharmaceutical companies marketing the products tested. In the case of foods or supplements, these treatments do not have to go through the FDA. [Food and Drug Administration] approval process. Thus, companies have little incentive to undertake rigorous and expensive studies.
There is another potential obstacle, as Dr. Rajani Katta, expert in dietetics and dermatology, said. MNT. âWe lack data on the safety of supplements in general because manufacturers do not have to investigate the safety at all before putting a supplement on the market. “
“The lack of comparison of nutritional or dietary modifications with conventional validated agents makes the data difficult to translate into the management of patients in the real world,” state the authors.
Researchers found different levels of evidence for significant associations of:
- a low glycemic index diet with acne
- fish oil and weight loss with psoriasis
- fish oils and probiotics with atopic dermatitis
- vitamins and botanical extracts with vitiligo
They also found “rare” evidence of the relationship that diet and nutrition have with bullous disorders and
However, the review found that a diet low in histamine may be helpful for episodic urticaria, and hot and spicy foods can trigger rosacea.
“Much of the role of diet in skin disorders,” the journal explains, “is complementary at best and does not modify disease.”
Dr Farris told MNT, âDermatologists should keep abreast of the literature when it comes to nutrition and supplements so that they can offer their patients a more holistic approach to treating skin disorders. “
Dr Katta said: “There are several supplements that I am monitoring closely as the preliminary studies are showing promise.” She cites in particular:
- “The use of
nicotinamidein the prevention of skin cancer other than melanoma in people with a history of skin cancer.
- The use of prebiotics and probiotics in the treatment of atopic dermatitis – although we have a number of randomized controlled trials, it has been difficult to translate the results of these trials into actual patient care as the trials have used such different doses, types and durations of further treatment.
- Studies of foods offering additional photoprotection, such as tomatoes and grapes.
- Using Zinc Supplements for Acne Treatment – some preliminary studies have shown benefits, but again, with so many different forms, doses, and durations, it’s difficult to translate the studies into recommendations for practical treatment.
The study authors are also concerned about the quality of the supplements that the companies market.
Notably, they write, there are various unapproved combinations that are permitted as dietary supplements, making their composition and rationale difficult to discern in skin disorders.
Dr Katta also cautioned: âAn important point about this review is that it focuses on published efficacy reports, not on safety issues. This is an important consideration as we have many reports of potential security issues with OTC. [over-the-counter] food supplements.”