Psoriasis is a very common dermatosis that affects the 2% of the general population with variable severity. Psoriasis is of multifactorial origin, in other words, caused by various factors that act on a genetic predisposition and cause skin inflammation.
Among the risk factors described there is accumulating evidence that nutrition plays a role. This post summarizes the scientific studies made public about nutritional and dietary strategies to improve psoriasis, the benefits of some dietary supplements and probiotics.
What is psoriasis and how is it treated?
The psoriasis It is a very common dermatosis which affects up to 2% of the population worldwide. Its treatment depends on the severity and includes topical treatments in the form of creams, systemic pills and phototherapy.
However, on repeated occasions the patient asks us what to eat, if there is any guideline in his diet to improve the psoriasis he suffers from.
On other occasions, the patient demands a more comprehensive approach, towards modern medicine, in which we treat their psoriasis in a more global way. The link between psoriasis and nutrition is widely studied in scientific literature; we can summarize it in three fundamental points: diet as a strategy, the use of nutritional supplements and probiotics.
Nutrition and diet strategies to improve psoriasis: What should I eat?
Little, undoubtedly. The obesity is a risk factor very important in psoriasis, and it is bidirectional, in other words, obesity worsens psoriasis and psoriasis promotes obesity (1). Obese patients have twice the risk of having psoriasis than those who are not obese.
Several lines of research suggest that adipocytes and their inflammatory molecules, adipokines, play a role in skin inflammation and in the hypothalamus, the main hunger regulatory center. Obesity releases a multitude of mediators into the blood that produce a situation inflammatory in the body. Leptin, a major intake-regulating hormone, is elevated in patients with psoriasis compared to healthy controls (2).
Obesity also has many implications for psoriasis treatments, as follows:
- When the patient loses weight, the response to treatments is better or they even stop needing them.
- Obesity increases the risk of side effects from systemic treatments (pills or injections).
The hypocaloric diet (800-1200 Kcal/day) combined with aerobic exercise at least 3 times a week for 30 minutes has been shown to improve psoriasis in a few weeks in many studies (3,4).
Components of the diet to improve psoriasis (3,5):
Diet rich in fish oils (omega-3 polyunsaturated fatty acids, PUFA), present in oily fish. They are the ones with the most evidence, due to their ability to reduce arachidonic acid and promote an anti-inflammatory environment.
Diet rich in monounsaturated fatty acids (MUFA) present in extra virgin olive oil, rich in oleic acid. Low MUFA intake worsens psoriasis and may cause it to progress. This study is in line with several others published about MUFAs and their anti-inflammatory capacity.
Regarding the type of global diet, Mediterranean diet takes the cake (3,4,5). We have plenty of scientific evidence that eating patterns rich in fruits, vegetables and fish are associated with a reduction in global markers of inflammation. In this situation it seems logical as it has been shown in numerous studies that the Mediterranean Diet improves psoriasis.
exist others publications that address different diet options to improve psoriasis, but with more limited scientific evidence, so their recommendation is not clear today (3):
- Gluten-free diet: it has been clearly shown to be beneficial in patients with celiac disease, also latent, and psoriasis (5).
- Vegetarian diet.
- Low carbohydrate diet.
Beneficial food supplements to treat psoriasis
Vitamin D. has been shown to have an anti-inflammatory role through the regulation of regulatory T lymphocytes. It should undoubtedly be supplemented in cases of deficiency since its deficiency can worsen psoriasis (3,4). However, its supplementation in patients with normal levels of vitamin D has not shown clear benefit (5,6). As a dermatologist who is an expert in psoriasis and phototherapy in Madrid, I do use it as a supplement in the patients I treat for psoriasis with phototherapy, due to its ability to protect the skin from the sun.
Fish oil and omega 3 supplements. They have been shown in numerous clinical trials to be beneficial in patients with psoriasis and other dermatoses (6). They must be maintained for long periods of up to 6 months to achieve effective benefit in psoriasis.
Supplements antioxidants In general, with vitamins (Vitamins A, E, C, folic acid, group B vitamins), trace elements such as Copper, Zinc, Iron, Magnesium and Selenium, coenzyme Q10 for its antioxidant capacity. They have demonstrated their positive effects in important studies (7,9).
- Zinc Supplements: Zinc is a trace element that is capable of regulating the immune response. The evidence of supplementing zinc in psoriasis is controversial, thus we find studies in which they have shown improvement and others have not (7,8).
- Selenium supplements: This is a trace element with antiproliferative capacity. Low selenium levels can worsen psoriasis (9).
Complementary medicinal plants or as an option to improve psoriasis
Medicinal plants are increasingly used and we have various studies and clinical trials published in quality scientific literature in which they demonstrate effectiveness in psoriasis. Such is the case of Dunaniella. bardawil, TwHF( Tripterigium wilfordii), Azadirachta indica (Neem tree) or Turmeric. Longa. However, at the current time we do not have guides for its use.
Polypodium Leucotomos
It is an extract of a fern (patented under the name of Fernblock) which has been shown to reduce the response of CD4 lymphocytes when taken orally. Studies of this compound were carried out in Spain years ago and demonstrated a mild to moderate benefit in half of the treated patients (10).
It is available sold in pharmacies and until a few years ago it was financed by the National Health System. We can say that it is the only plant available in Western medicine for the treatment of psoriasis.
This compound is also of special interest as an antioxidant and oral sunscreen.
Probiotics, prebiotics and synbiotics that help against psoriasis
Probiotics, prebiotics and synbiotics are other components to consider along with herbal remedies and dietary advice to improve psoriasis.
As a brief introduction, I will first break down what each of them is:
- Probiotic: a microorganism that, taken, produces health benefits.
- Prebiotic: a substance that is ingested promotes the growth of some bacteria in the colon that are beneficial for health
- Symbiotic: It is the mixture of the previous two
Bifidobacterium infantis
To date we only have one study of a probiotic in psoriasis: it is Bifidobacterium infantis 356624 (yes, probiotics have a serial number along with the name of the bacteria).
This bacteria was ingested for 8 weeks by psoriasis patients who were compared to psoriasis patients who did not take it. It was shown that it is capable of reducing the classic markers of inflammation in psoriasis such as TNF-alpha and the interleukin 6 or C-reactive protein; However, it did not translate into a clear benefit for skin lesions, so, even though it seems promising, B. infantis more studies are needed.
Conclusion
Psoriasis benefits from antioxidant rich diet (fruits, vegetables), fish, especially blue, and olive oil in a controlled calorie intake. Approximately, Mediterranean diet.
Furthermore we can add blue fish and antioxidant supplements diet to improve psoriasis. Supplementing with vitamin D or selenium makes sense in patients with a deficiency, since this situation can worsen psoriasis.
There is evidence of improvement in psoriasis with some oral plants (herbal medicine), but we currently have no guidelines for its use. The extract of Polypodium leucotomos It is safe orally and can improve in about half of patients. And at probiotics they have abandoned.
Bibliography
1. Carrascosa JM, Rocamora V, Fernandez-Torres RM et al. Obesity and psoriasis: inflammatory nature of obesity, link between psoriasis and obesity and therapeutic implications. Actas Dermosifiliofr 2014; 105: 31-44.
2. Zhu KJ, Zhang C, Li M. Leptin levels in patients with psoriasis: a meta-analysis. Clin Exp Dermatol 2014; 222: 113-127.
3. Barrea L, Nappi F, Di Somma C, et al. Environmental risk factors in psoriasis: the nutritionist's point of view. Int J Environ Res Public Health 2016; 13: 743-755.
4. Zuccotti E, Oliveri M, Girometa C, et al. Nutritional strategies for psoriasis: current scientific evidence in clinical trials. Eur Rev Med Pharmacol Sci 2018; 22: 8537-8551.
5. Ford A, Siegal M, Bagel J. A dietary recommendations for adults with psoriasis or psoriatic arthritis from the medical board of the national psoriasis foundation. JAMA Dermatol 2018; 154: 934-950.
6. Millsop JW, Bathia BK, Debbaneh M, et al. Diet and psoriasis, part III: role of nutritional supplements. J Am Acad Dermatol 2014; 71: 561-569.
7. Smith N, Weyman A, Tausk et al. Complementary and alternative medicine for psoriasis: a qualitative review of the clinical trial literature. J Am Acad Dermatol 2009; 61: 841-856.
8. Wacemicz M, Socha K, Soroczyska J, et al. Selenium, zinc, copeer concentration, Cu/Zn binding, total antioxidant status and serum c-reactive protein of psoriasis patients treated with narrowband ultraviolet B phototherapy: a case-control study. J Trace Elem Med Biol 2017; 44: 109-114.
9. Kharaeva Z, Giostova E, De Luca et al. Clinical and biochemical effects of supplementation with coenzyme Q10, vitamin E and selenium in patients with psoriasis. Nutrition 2009; 25: 295-302.
10. Padilla HC, Laínez H, Pacheco JA. A new agent (hydrophilic fraction of polypodium leucotomos) for the treatment of psoriasis. Int J Dermatol 1974; 13: 276-282.
11. Groeger D, O'Mahoni L, Murphy EF, et al. Bifidobacterium infantis 35624 modulates host inflammatory processes beyond the intestine. Gut Microbes 2013; 4: 325-339.
English 
Español de Argentina 
Français 
Português do Brasil 