Non-alcoholic fatty liver disease (NAFLD) occurs when fats accumulate in the liver in the absence of excess alcohol intake and if unmanaged can advance to severe liver disease known as cirrhosis. NAFLD and cirrhosis can be associated with obesity, muscle wastage and nutrient deficiencies. This review of 165 papers aimed to discuss muscle wastage and nutrient deficiencies in patients with obesity and cirrhosis with a view to making supplementation recommendations. The authors first discussed that the risk of muscle wastage in patients with obesity and cirrhosis is high and when combined with obesity may affect other chronic diseases and impact the progression of NAFLD to cirrhosis. The paper then discusses that vitamin and mineral deficiencies are common in patients with cirrhosis possibly due to reduced intake, poor absorption and the reduction of carrier protein production in the liver. Deficiencies in vitamins D and E and zinc and magnesium were extensively featured. Protein and calorie intake were also reviewed and although weight loss should be encouraged in patients with obesity and cirrhosis, over-restriction could exacerbate muscle breakdown. Any low-calorie diets should contain adequate protein content. Bariatric surgery, in patients with obesity and cirrhosis needs to be performed on a case-by-case basis involving many different medical disciplines. It was concluded that obesity and cirrhosis are commonly occurring simultaneously and poses a management challenge for medical professionals. This paper could be used by health care professionals to understand the possible nutritional deficiencies that need to be monitored in patients with obesity and cirrhosis and where bariatric surgery may be indicated.