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If you have psoriasis, you’ve probably tried it all: creams to pills, sulphur baths…maybe you’re wondering if an anti-inflammatory diet can help. Here’s what the research says, and 6 steps you can take to shift your diet.

Psoriasis is a chronic inflammatory disease with complex origins1-8 resulting in impaired skin barrier function, oxidative damage, T cell dysregulation and a Th17 inflammatory response7,8. People with psoriasis often have lower levels of micronutrients such as vitamin D1,4,6, in addition to the body’s natural antioxidants superoxide dismutase (SOD) and glutathione7.

It makes a strong case for turning to nutrition, which can be powerful medicine in the fight against chronic inflammation. However, nutrition is not often discussed as a potential therapy in psoriasis due to the lack of strong evidence to guide decision making.

What does the evidence say about nutrition and psoriasis?

In 2018, a systematic review on the role of diet in psoriasis was published that essentially turned up zilch. It recommended weight loss to reduce inflammation in those with obesity, it also supported topical vitamin D use and potentially oral vitamin D but cited inconclusive evidence1. Other reviews argue that omega 3 fatty acids, oral vitamin D and selenium show potential but agree that the evidence is conflicting4,6.

While the data for single nutrients is inconsistent, one trial found that a combination of micronutrients, including zinc and selenium improved disease severity score6. Turmeric has also been studied, alongside other therapies with potential benefit6.

Going gluten free is a popular strategy online; some evidence suggests that it may be helpful for those with elevated AGA levels, but this is debated in the research3.

The Gut-Skin Connection in Psoriasis

Since psoriasis is a chronic inflammatory condition, you might expect that a connection to the gut is also at play…and you’d be right. The gut, nervous system and the skin are intimately connected. In fact, those with psoriasis are more likely to have celiac disease or inflammatory bowel disease than those without2,3. There is thought to be genetic links between inflammatory bowel disease and psoriasis that impact the inflammatory process; gut barrier dysfunction present in digestive disease may also exacerbate psoriasis2.

Research confirms that the microbiota, or bacteria, of the skin and the gut are notably different in psoriasis; for example, one trial noted less Akkermansia muciniphilia in the guts of those with psoriasis8. An imbalanced, or dysbiotic, microbiota can cause increases in oxidative damage and alter immune responses which may make psoriasis worse8. Probiotics, which stand in for the protective functions of your own bacteria, have been shown in early research to decrease Th17 responses in psoriasis8.

What to eat when you’ve got psoriasis

I know that so far, it may not seem like there are a lot of options when it comes to nutrition.

However, you’ve got to eat…so when the evidence doesn’t give you a clear roadmap, opt for safe anti-inflammatory measures that will protect your health. While its efficacy in psoriasis can’t be confirmed, no one would say that an anti-inflammatory diet rich in colourful plant foods isn’t a healthy way to live. And, perhaps it may just lessen inflammation enough to support healthier skin. In one trial, improved psoriasis disease score was associated with a higher Mediterranean diet score, suggesting that an anti-inflammatory diet may support the disease5.

And this is where nutrition research needs to improve. Because psoriasis is a complex disease, expecting a single nutrient to overcome the disease process is unrealistic – and we’ll probably never find a magic nutrient that reverses the disease. However, looking holistically at a total diet approach is always a good idea and may truly shift the needle. Anecdotally, I’ve had many people tell me that changing their diet has greatly improved their psoriasis; central to this has been a probiotic and adopting a more plant-based, less meat centric diet.

If you’re ready to make the change, I suggest working with a dietitian to help you make the following shifts:

  1. Move towards a lower starch, moderate fat plant-based diet. In the Med Diet study5, both consumption of olive oil and fish were both independently associated with disease score. What do those things have in common? Healthy fats. So anchoring your meal in vegetables, with a portion of protein and plenty of healthy fats is a wise idea.
  2. Avoiding refined grains, and keeping 100% whole grain portions modest unless you are very active, will help keep your fibre intake up and blood sugars balanced to avoid triggering inflammation.
  3. Try to fill half your plate with colourful fruits and vegetables to increase intake of anti-inflammatory phytochemicals. It is thought that polyphenols called proanthocyanidins in grapes, apples, cocoa, cranberries and black currants may help regulate Th17 pathways and fight over-proliferation of skin cells7.
  4. Eat 1-3 tablespoons of omega 3-rich seeds such as hemp, ground flax or chia daily and consider an omega 3 supplement high in EPA if you’d like to ramp up your efforts.
  5. Take a clinical strength probiotic for a minimum of 12 weeks to assess if it has benefit for you. Look at Probiotic Chart (Canada/US) to select an evidence-based product.
  6. If you are having difficulty eating enough legumes, nuts and seeds to keep your mineral intake high, consider a multi mineral supplement that includes selenium, zinc and copper to support cellular function.

Psoriasis affects millions and can be a debilitating disease. Find a supportive care team and work with your physician to select the best treatment course for you and take care of your body at a foundational level by taking an anti-inflammatory approach to nutrition.

Anti Inflammatory Recipes

Ready for a one-on-one nutrition consult? Meet with our team!

Photo Credit: Alyssa Dawson

References

  1. 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
  2. Pietrzak, Daniel et al. “Digestive system in psoriasis: an update”  Archives of dermatological researchvol. 309,9 (2017): 679-693.
  3. Bhatia, Bhavnit K et al. “Diet and psoriasis, part II: celiac disease and role of a gluten-free diet”  Journal of the American Academy of Dermatologyvol. 71,2 (2014): 350-8.
  4. Millsop, Jillian W et al. “Diet and psoriasis, part III: role of nutritional supplements”  Journal of the American Academy of Dermatologyvol. 71,3 (2014): 561-9.
  5. Barrea, Luigi et al. “Nutrition and psoriasis: is there any association between the severity of the disease and adherence to the Mediterranean diet?”  Journal of translational medicinevol. 13 18. 27 Jan. 2015, doi:10.1186/s12967-014-0372-1
  6. Zuccotti, E., et al. “Nutritional strategies for psoriasis: Current scientific evidence in clinical trials.” Eur. Rev. Med. Pharmacol. Sci22 (2018): 8537-8551.
  7. Lai, Rui, et al. “Proanthocyanidins: novel treatment for psoriasis that reduces oxidative stress and modulates Th17 and Treg cells.” Redox Report23.1 (2018): 130-135.
  8. Benhadou, Farida et al. “Psoriasis and Microbiota: A Systematic Review” Diseases (Basel, Switzerland)vol. 6,2 47. 2 Jun. 2018, doi:10.3390/diseases6020047