Psoriasis is a chronic inflammatory dermatosis that is characterized with formation of erythemato-squamous infiltrative plaques on the skin, predominantly located on the elbows, knees and scalp.

The disease incidence among the general population is significant, between 0.6% and 4.8%, and depends on geographic (climate), ethnic and behavioral factors.

Among the proven risk factors are: genetic predisposition, bacterial and viral infections and some harmful habits (smoking, alcohol, drug abuse).

Despite the unknown etiology, the knowledge about the immunopathogenesis of psoriasis has expanded in the last years.

The current view is that T-lymphocytes play a major role in psoriasis together with keratinocytes and other cell types (e.g. dendritic cells, polymorphonuclear leukocytes, mast cells) which are involved in the innate and acquired immunity.

The discovery of Th17-cells in 2005 led to the establishment of a new model for the immunopathogenesis of psoriasis in which cytokines released from Th1 and Th17-cells participate.

Comorbidity is found between psoriasis and some diseases such as: cancer, cardiovascular, metabolic, mental and cognitive abnormalities. Increased incidence of obesity is observed in patients with psoriasis, as common cytokines are identified in both diseases which explains the metabolic disorders and creates high cardiovascular risk.

Nutrition can affect both the initiation and the progress of an already occurred disease. Low-caloric diets and fasting, as well as foods low in gluten and animal fat, possess positive effect upon psoriasis and reduce its frequency and periods of exacerbation.

Although there is no approved specific diet in psoriasis, a significant improvement is reported in the literature when gluten-free, vegetarian or rice diet is followed, as well as when supplementation with fish oil, vitamin D, taurine and zinc sulfate is performed.

Foods containing anti-oxidants, beta-carotene, folates, omega-3 fatty acids and zinc are recommended, as they can modulate the immune response that is relevant to the disease. Psoriasis diet is essential for maintenance of good quality of life of the patients according to almost all authors.

It is reported in the literature that patients with psoriasis have an increased intestinal permeability and this gives reason to recommend restriction of foods rich in animal proteins and their replacement with vegetable ones from legumes and nut fruits, as well as the elimination of grain gluten-containing foods (wheat, rye, oats).

There is data that the regular intake of carrots and fresh fruits, rich in anti-oxidants and carotene, is in reverse correlation with the risk of psoriasis and has some protective effect.

The established pattern of nutrition shows in a significant part of the patients that it may be characterized as healthy, but not completely adequate to the diagnosis, as it has no specific protective and therapeutic potential.

The high daily consumption of bread, pasta, potatoes, milk and dairy products is a negative tendency that may trigger latent gluten enteropathy and sensitizes the organism.

A positive effect upon the severity of skin lesions and intestinal permeability possess the controlled dietary regime low in animal protein and fat, with limited intake of mono- and disaccharides, rich in complex carbohydrates, with consumption of herbal teas and exclusion of alcohol for at least six months.

Diet recommendations in psoriasis:

Food group
Recommended foods

Foods which should be avoided or excluded

Meat

Fish, white poultry meat
Red meat, fried, with high fat content, sausages and preserved meat
 Fruits

All types

None

Vegetables

 All vegetables (leafy, cabbage, cauliflower, broccoli, carrots and other root vegetables), without Solanaceae family
Potatoes, tomatoes, eggplants, peppers – green and red*

Cereals and food rich in starch
Rice, corn, wholegrain foods

Confectionery, foods rich in starch, a combination of more than one starch food, wheat, rye or oats flour and their products
Milk/dairy products
Limited amount of low-fat milk (<1%)
Salty, refined milk foods, imitations of dairy products and butter, hydrogenated fat (margarine) and products containing them

Desserts

Fruits

Foods rich in fat

Beverages
Water, fruit juices, fruit and herbal tea, saffron tea (Crocus sativus)
Carbonated drinks rich in fructose, containing artificial sweeteners, alcoholic beverages

Nut fruits

All types

None

*The table is adapted from A. Brown et al.

Literature:

  1. Alinos, Kaklamati, et al. Dietary factors in relations to rheumatoid arthritis a role of olive oil and cooked vegetables. The Amer. J Clin Nutr, 1999, Vol 70, 6, pp 1077–1082.
  2. Boelsma , et al. Nutritional skin care: health effect of micronutrients and fatty acids. Amer. J Clin Nutr, 2001, 73, pp 853–64.
  3. Brown, et al. Medical Nutrition Therapy as a Potential Complementary Treatment for Psoriasis-Five Case Reports. Altern Med Rev, 2004, 9 (3), 297– 307.
  4. Chalmers, J.G., B.  Kirby.  Gluten  and  psoriasfree.  Brit  J  Dermatol,  2000, 142, pp 5–17.
  5. Eugene, Farber, J. Brian, Nickoloff, Bernard Recht. Jorma E. Fraki. Stress, symmetry, and psoriasis: Possible role of neuropeptides. Journal of Ameri- can Academy of Dermatology, 1986, 14, 2, pp 305–311.
  6. Feldman, R. A quantitative definition of severe psoriasis for use in clinical practice. – J Dermat Practice, 2004, 15, 27–29.
  7. Проучване на храненето при пациенти с псориазис и насоки за оптимизиране на диетата – сп. “Наука Диететика” бр. 1, 2012 година