Unlocking the Link Between Diet and Improved Psoriasis Symptoms

Psoriasis is a chronic inflammatory disease that affects the skin. Red, thick patches with silvery scales develop, with the plaques causing the area to itch or become sore. This is the effect of new cells rapidly turning over and accumulating on the skin's surface.

Psoriasis can occur anywhere on the skin but the most commonly affected areas include the scalp, face, elbows and knees.

As with other autoimmune diseases, the exact cause of psoriasis is not known but genetics and environmental aspects are thought to play a role. Additionally, individuals with psoriasis are at increased risk for comorbidities, such as psoriatic arthritis, metabolic syndrome and cardiovascular disease.

Research suggests an elevated body mass index (BMI) is associated with more severe psoriasis symptoms and a decreased response to medication and other treatments. A 2018 systematic review, published in JAMA Dermatology, looked at several diet-related factors and how they impact psoriasis severity. They found that weight loss was associated with improved symptoms among individuals with an elevated BMI, specifically when following a hypocaloric diet. And, despite an increased risk of celiac disease among individuals with psoriasis, there was a lack of evidence to support the use of a gluten-free diet except when celiac disease or gluten sensitivity is present.

Some studies have found that foods with anti-inflammatory properties may help in the management of psoriasis severity. Obtaining the recommended amount of omega-3 fatty acids has been considered beneficial; however, results have been mixed when evaluating the effectiveness of oral fish oil supplements and psoriasis severity, so obtaining them through dietary sources is encouraged. Additional studies, but with low-quality evidence, have investigated the effect of a Mediterranean dietary pattern in patients with psoriasis, therefore a trial of this type of eating style may be considered along with conventional treatment. Additionally, some research suggests that vitamin D may be beneficial in symptom management.

Another area of interest is the use of a very low-calorie ketogenic diet (VLCKD) as a treatment for psoriasis due to its potential to decrease visceral adipose tissue and inflammation. However, there are currently few studies looking at VLCKD in managing this condition. Research so far has not determined whether the reduction in psoriasis severity was a result of the dietary intervention or due to overall weight loss, and more research is needed.

Although there are no evidenced-based nutrition guidelines or therapeutic diets currently available for psoriasis, registered dietitian nutritionists can assist patients and clients with lifestyle interventions to help lessen its severity. These include weight loss, when appropriate, and addressing any potential nutrient deficiencies.

Resources:

• National Institute of Arthritis and Musculoskeletal and Skin Diseases. Psoriasis. Accessed August 3, 2022.
• Escott-Stump, S. 2022. Nutrition & Diagnosis-Related Care, 9th Ed. Academy of Nutrition and Dietetics
• 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.
• Barrea L, Megna M, Cacciapuoti S, et al. Very low-calorie ketogenic diet (VLCKD) in patients with psoriasis and obesity: an update for dermatologists and nutritionists. Crit Rev Food Sci Nutr. 2022;62(2):398-414.