Psoriasis is an inflammatory skin disease that results in patches of dry, scaly skin that can be itchy or sore. This review looked at the evidence for a variety of nutritional and herbal strategies for reducing the risk and severity of psoriasis. Obesity is associated with both an increased risk of psoriasis, and increased severity of the disease, with obese patients being twice as likely to suffer from psoriasis as people of normal weight. Abdominal obesity in particular is associated with chronic low-grade inflammation that contributes to immune dysregulation. In obese patients, weight reduction via a low-calorie diet has been shown to reduce the severity of psoriasis. A Mediterranean-style diet, rich in extra virgin olive oil, fish, fruit vegetables, legumes, nuts and seeds is associated with a lower incidence of psoriasis. In contrast, a diet high in simple carbohydrates, high in arachidonic acid, and a low omega 3: omega 6 ratio is likely to drive inflammation, worsening severity of the disease. The microbiota plays a role in the development of psoriasis, with disruption of the gut and skin microbiomes both associated with psoriasis. In particular, psoriasis patients have a reduced abundance of Akkermansia muciniphilia in their gut. Several Lactobacillus strains have demonstrated potential for therapeutic effects in psoriasis patients when taken as a supplement. Common nutritional supplements used by psoriasis patients are fish oil, selenium, and zinc. In a review of the efficacy of fish oil supplementation, 12 of 15 trials showed a benefit. The evidence for zinc supplementation is less robust. There is limited data on the effectiveness of selenium supplementation, however low serum selenium levels are associated with increased psoriasis severity. Vitamin D levels are lower in psoriasis patients and correlate with disease severity. In individuals who are deficient, supplementing with vitamin D may prevent psoriasis-related comorbidities. Amongst the herbal and botanical remedies studied, neem, turmeric, Tripterygium wilfordii (Thunder God Vine), and the carotenoid-rich alga Dunaliella bardawil may reduce the severity of psoriasis. The review authors concluded that an integrated multidisciplinary approach should be considered for the management of psoriasis patients. Education to modify lifestyle and environmental risk factors is important. A collaboration between nutritionists and medical specialists with a holistic approach may be useful for psoriasis patients.