Here are some more interesting snippets from the research paper that Stewart-H posted:
Energy Intake and Food Selection
Studies have shown that symptoms of inflammatory diseases such as rheumatoid arthritis can be improved by fasting periods or low-energy diets. The prevalence and severity of psoriasis have been reported to be lower in periods of insecure food supply. Therefore, the disease may also be improved by low-calorie diets.
In one study, 20 patients with arthritis and various skin diseases were studied during a 2-week period of modified fast followed by a 3-week period of vegetarian diet. During fasting, some patients with psoriasis experienced an improvement, which persisted during the vegetarian diet.[14] The direct cause of these positive effects is not sufficiently explained, and various mechanisms are discussed. The most important reason is probably the lack of arachidonic acid (AA) intake. Another reason may be a reduction of oxidative stress due to calorie restriction, because psoriasis appears to be associated with oxidative stress. A vegetarian diet may be beneficial because it is associated with a reduced AA intake. As psoriasis is positively connected with body mass index (BMI),[18,19] weight reduction is recommended for obese patients. Short-term fasting periods may improve severe symptoms and thus can be suggested for patients with a BMI in the upper range. There have been several observations indicating that alcohol consumption is highly prevalent in patients with psoriasis. As alcohol stimulates the release of histamine, skin lesions can aggravate as a consequence. Moreover, a high alcohol intake may be accompanied by an excessive intake of high-fat foods and saturated fats and a low intake of vegetables and fresh fruit. Therefore, alcohol intake should be restricted in psoriasis.
Polyunsaturated Fatty Acids;
. Food sources of AA are only animal-derived foods such as meat and egg yolk. The fatty acids [ch945]-linolenic acid, EPA and DHA are the most abundant n-3 fatty acids in food. [ch945]-Linolenic acid is found in linseed and walnut oil, whereas EPA and DHA are typical fish oil fatty acids, which are contained in oily fishes such as mackerel and herring. Eicosanoids derived from AA can exacerbate inflammatory processes and those derived from EPA exhibit anti-inflammatory properties.[25]
.......... the daily intake of oily fish such as mackerel, sardine, salmon, pilchard, kipper or herring, which are rich in n-3 fatty acids, might be a useful adjunct in the treatment of psoriasis.
Several trials have demonstrated the anti-inflammatory effects in psoriasis of fish oils which are rich in n-3 polyunsaturated fatty acids.
Overproduction of AA-derived eicosanoids has been implicated in many inflammatory and autoimmune disorders and also in psoriatic skin lesions. Low dietary AA intake which is typical for vegetarian diets can also reduce LTB4 synthesis and may additionally improve inflammation.
Oxidative Stress and Antioxidants;
Oxidative stress and increased free radical generation have been linked to skin inflammation in psoriasis. Patients with psoriasis exhibit several markers of oxidative stress and show impaired antioxidant status. In an Italian case-control study with 316 patients with psoriasis and 366 controls, dietary intake was assessed by a semiquantitative food frequency questionnaire and data were adjusted for age, sex and BMI. Psoriasis risk (odds ratio) was significantly inversely related to the intake of carrots, tomatoes and fresh fruit as well as to the [ch946]-carotene intake (editors note; i.e. as the intake of fruit & veggies goes up, symptoms of p go down!). The intake of green vegetables showed an inverse association, with borderline statistical significance. The consumption of vegetables and fruits may be beneficial in psoriasis due to their high content of various antioxidants such as carotenoids, flavonoids and vitamin C.
A sufficient status of antioxidants (e.g. vitamin C, vitamin E, [ch946]-carotene and selenium) may be helpful to prevent an imbalance of oxidative stress and antioxidant defence in psoriasis. While ascorbic acid acts as a water-soluble antioxidant, [ch945]-tocopherol (vit E) is a chain-breaking antioxidant, [ch946]-Carotene displays antioxidant activity by scavenging free radicals, Selenium is essential for the function of a number of selenoproteins such as glutathione peroxidases and thioredoxin reductase which take part in the antioxidant defence. To date, only a few studies have investigated the effect of antioxidant supplementation on psoriasis symptoms.
Vitamin D3 and Analogues
In Europe, prevalence of insufficient vitamin D status is high, as UVB radiation from sunlight is negligible from October to April at the latitude of 52°N and from November to February at 42°N. In contrast, skin synthesis of vitamin D is possible throughout the year at 32°N or closer to the Equator. Hypovitaminosis D is even more prevalent in older adults because of limited outdoor activities and decreased capacity of vitamin D synthesis of the skin compared with younger adults. In an epidemiological survey of 11 European countries, vitamin D deficiency was found in 36% of elderly male and 47% of elderly female subjects.
As insufficient vitamin D is a general problem, oral vitamin D supplementation may be considered in patients with psoriasis who do not use topical vitamin D analogues.
