Cancers are the leading cause of death worldwide, and various modalities of cancer treatment, such as surgery, radiation therapy, and pharmacological therapies, have been applied. Malnutrition and a loss of muscle mass are encountered frequently in cancer patients and adversely affect the clinical outcomes. Therefore, screening for, monitoring, and treating malnutrition are important procedures in treating cancer patients. This paper reviews the guidelines as well as comparative studies describing the nutritional support provided to cancer patients and describes the evidence-based guidelines and recommendation for each topic.

Bariatric surgery is considered one of the most effective methods of achieving long-term weight loss in morbidly obese patients. Nevertheless, bariatric procedures are associated with a number of complications, and nutrient deficiencies can lead to deleterious consequences. Furthermore, the diet of patients prior to bariatric surgery is often of poor nutrition quality that does not meet the recommended dietary guidelines for micronutrient intake. Therefore, optimization of the postoperative nutritional status should begin before surgery. This review covers the essential information about micronutrient management in patients before and after bariatric surgery.