Generalized Pustular Psoriasis (GPP)

Generalized pustular psoriasis (GPP) is a rare and severe form of psoriasis characterized by sudden and recurrent eruptions of small pustules over large areas of the body with erythema and edema. Skin manifestations can be accompanied by fever, fatigue, muscle weakness, headache, nausea, rapid pulse, inflammation, itching, and joint pain.1 There are no specific dietary recommendations for patients with GPP. However, several studies have investigated the influence of nutrition on psoriasis and proposed dietary recommendations for patients with psoriasis.2

Dietary Recommendations for Psoriatic Diseases

In 2018, the National Psoriasis Foundation Medical Board made evidence-based dietary recommendations for adults with psoriasis or psoriatic arthritis that can be used in combination with medical therapies. The board advises against relying solely on these dietary interventions for treatment and states that they should always be used in conjunction with standard medical therapies.2

Recommendations for Psoriasis

The recommendations for patients with psoriasis include3-5

  • Strong recommendation for overweight or obese adults with psoriasis (body mass index [BMI] of 25 or higher) to reduce weight with a low-calorie diet
  • Strong recommendation for adults with psoriasis who have a confirmed diagnosis of celiac disease to follow a gluten-free diet
  • Weak recommendation for patients who test positive for serologic markers of gluten sensitivity to try a gluten-free diet for 3 months 
  • Weak recommendation for adults with psoriasis to try a Mediterranean diet, including using extra virgin olive oil as the main cooking oil, increasing their daily intake of vegetables (at least 2 servings) and fruits (at least 3 servings), and increasing their weekly intake of legumes (at least 3 servings), seafood (at least 3 servings), nuts (at least 3 servings), and sofrito sauce, consisting of tomatoes, onions, garlic, and olive oil (at least 2 servings)
  • Weak recommendation to increase the intake of monounsaturated fatty acids, omega-3 polyunsaturated fatty acids (PUFAs), complex carbohydrates, and fiber and reduce the intake of total energy, simple carbohydrates, saturated fatty acids, total PUFAs, omega-6 PUFAs, and the omega-6:omega-3 PUFA ratio.

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Recommendations for Psoriatic Arthritis

The recommendations for patients with psoriatic arthritis include2,6:

  • Recommendation for overweight or obese adults with psoriatic arthritis (BMI of 25 or higher) to reduce weight with a low-calorie diet 
  • Weak recommendation for adults with psoriatic arthritis to take oral vitamin D supplements (0.5 μg alfacalcidol or 0.5-2.0 μg calcitriol daily).

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Impact of Diet on Psoriasis

Patients with psoriasis who were members of the National Psoriasis Foundation were surveyed in a US national study to assess their dietary behaviors. The survey revealed that many patients believed the severity of their psoriasis was influenced by their diet. The respondents counted sugar, gluten, alcohol, nightshade vegetables (paprika, peppers, eggplant, tomatoes, white potatoes), junk food (chocolate, candy, pastries, sweets, french fries, potato chips), and wheat flour products to be the most common triggers of psoriasis. The respondents also reported a positive skin response with the addition of fish oil or omega-3 fatty acids, vegetables, oral vitamin D supplements, probiotics, organic foods, and fruits.7

Although the exact mechanism by which these foods trigger psoriasis is not known, prior studies have indicated alterations in the gut microbiome (favoring injurious bacteria in some cases), irritation of the intestinal lining, and increased immune response as possibilities.7

A recent review examining the role of diet and supplements in managing psoriasis found that certain diets may benefit this patient group, including low-calorie diets, gluten-free diets, and the Mediterranean diet.3

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Low-Calorie Diet

Low-calorie diets were found to be useful as adjunctive therapies for obese individuals with psoriasis. Patients in the low-calorie diet group reported a better response to systemic psoriasis medication than those who did not follow the diet.8 In addition, low-calorie diets may help reduce adverse effects of biologic treatments such as tumor necrosis factor (TNF)-alpha inhibitors.9

Gluten-Free Diet

A gluten-free diet was found to benefit psoriasis patients with comorbid celiac disease or gluten sensitivity.10,11

Mediterranean Diet

Although the exact mechanism of the beneficial effects of the Mediterranean diet is not known, the diet may impart anti-inflammatory benefits due to the high intake of whole fruits and vegetables rich in antioxidants. In addition, the high consumption of extra virgin olive oil (high polyphenol content) in this diet may also help reduce inflammation associated with psoriasis.3

A review also noted that the Western diet — a diet containing high amounts of sugar and fat — must be avoided because of its potential to cause inflammation and negative effects on health.3 

Supplements such as vitamin D, omega-3 PUFAs, and selenium have been shown to provide benefits in clinical studies; however, there is a lack of strong evidence to support their recommendation. Although herbal supplements, particularly curcumin and Tripterygium wilfordii, have shown promising results as adjuvant treatment in psoriasis, their use requires further investigation and they are not currently recommended.3

Probiotics, which are known to alter the gut microbiome, have shown promising results in patients with psoriasis in many clinical studies, with some reports of negative outcomes. Thus, further research is needed to fully assess their efficacy in patients with psoriasis.3

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  1. Romiti R, Hirayama ALDS, Arnone M, Magalhães RF. Generalized pustular psoriasis (von Zumbusch). An Bras Dermatol. 2022;97(1):63-74. doi:10.1016/j.abd.2021.05.011
  2. Ford AR, Siegel M, Bagel J, et al. Dietary recommendations for adults with psoriasis or psoriatic arthritis from the Medical Board of the National Psoriasis Foundation: a systematic review. JAMA Dermatol. 2018;154(8):934-950. doi:10.1001/jamadermatol.2018.1412
  3. Chung M, Bartholomew E, Yeroushalmi S, Hakimi M, Bhutani T, Liao W. Dietary intervention and supplements in the management of psoriasis: current perspectives. Psoriasis (Auckl). 2022;12:151-176. doi:10.2147/PTT.S328581
  4. Barrea L, Balato N, Di Somma C, et al. Nutrition and psoriasis: is there any association between the severity of the disease and adherence to the Mediterranean diet? J Transl Med. 2015;13:18. doi:10.1186/s12967-014-0372-1
  5. Barrea L, Macchia PE, Tarantino G, et al. Nutrition: a key environmental dietary factor in clinical severity and cardio-metabolic risk in psoriatic male patients evaluated by 7-day food-frequency questionnaire. J Transl Med. 2015;13:303. doi:10.1186/s12967-015-0658-y
  6. Di Minno MND, Peluso R, Iervolino S, Russolillo A, Lupoli R, Scarpa R; CaRRDs Study Group. Weight loss and achievement of minimal disease activity in patients with psoriatic arthritis starting treatment with tumour necrosis factor α blockers. Ann Rheum Dis. 2014;73(6):1157-1162. doi:10.1136/annrheumdis-2012-202812
  7. Afifi L, Danesh MJ, Lee KM, et al. Dietary behaviors in psoriasis: patient-reported outcomes from a U.S. national survey. Dermatol Ther (Heidelb). 2017;7(2):227-242. doi:10.1007/s13555-017-0183-4
  8. Gisondi P, Del Giglio M, Di Francesco V, Zamboni M, Girolomoni G. Weight loss improves the response of obese patients with moderate-to-severe chronic plaque psoriasis to low-dose cyclosporine therapy: a randomized, controlled, investigator-blinded clinical trial. Am J Clin Nutr. 2008;88(5):1242-1247. doi:10.3945/ajcn.2008.26427
  9. Campanati A, Molinelli E, Ganzetti G, et al. The effect of low-carbohydrates calorie-restricted diet on visceral adipose tissue and metabolic status in psoriasis patients receiving TNF-alpha inhibitors: results of an open label controlled, prospective, clinical study. J Dermatolog Treat. 2017;28(3):206-212. doi:10.1080/09546634.2016.1214666
  10. Michaëlsson G, Gerdén B, Hagforsen E, et al. Psoriasis patients with antibodies to gliadin can be improved by a gluten-free diet. Br J Dermatol. 2000;142(1):44-51. doi:10.1046/j.1365-2133.2000.03240.x
  11. Passali M, Josefsen K, Frederiksen JL, Antvorskov JC. Current evidence on the efficacy of gluten-free diets in multiple sclerosis, psoriasis, type 1 diabetes and autoimmune thyroid diseases. Nutrients. 2020;12(8):2316. doi:10.3390/nu12082316

Reviewed by Kyle Habet, MD, on 5/30/2023.