Protein-calorie malnutrition (PCM) is a transversal condition to all stages of chronic liver disease (CLD). Evidence based observations suggest that PCM is present in 65–90% of patients with advanced disease. Numerous studies have shown that a direct relationship between the severity of liver disease and the degree of malnutrition. Various complications linked with PCM are esophageal varices, hepatic encephalopathy (HE), hepatorenal syndrome, impaired liver function and regeneration capacity and increased surgical morbidity and mortality. Moreover, malnutrition is regarded as an independent predictor of mortality in patients with CLD. 

Patients suffering from cholestatic liver disease are more prone to have calorie deficiency and have an increased risk of fat-soluble vitamin deficits. Besides, patients with hepatocellular disease are associated with protein deficiency while patients with cirrhosis have an elevated risk of micronutrient deficiency. Thus, early diagnosis of micro or macronutrient deficiencies is required, as intervention of nutritional supplements at early stages of liver disease can reduce risk of infection, in-hospital mortality, and even has the potential to improve liver function. In order to make a prompt diagnosis, screening of all patients with CLD for identifying those at risk of preventable complications is necessary.

Patients with CLD are recommended a standard diet with additional supplements, if necessary. Usually, a practically normal diet is given and restrictions are individualized. The main objective for these patients is to improve the level of PCM, to get an adequate amount of nutrients, to attain a positive nitrogen balance and to avoid hepatotoxic agents. Owing to patients increased susceptibility to infections, food should be welvl cooked, and should be distributed in 5–7 small daily meals so as to avoid protein overload and adverse effects of nausea/vomiting. In addition, scheduling of meal is highly crucial in comparison to the amount of food ingested, as suppression of protein degradation occurs during the postprandial period.  In these patients, a late evening snack is preferable as it exhibits positive effect on the nitrogen balance, increases muscle mass by reversing sarcopenia, which in turn can improve quality of life, reduce the severity and frequency of HE and offers better prognosis. This helps in avoiding fasting periods longer than 6 h and reduce the catabolism rate.  

Generally foods with high caloric content containing at least 50 g of carbohydrates and enriched with branch chained amino acid (BCAA), mainly leucine, isoleucine and valine are advisable. BCAA can help in promoting protein synthesis, reducing the concentration of nitrogenous products and prevents the synthesis of false neurotransmitters, implicated in the development of HE. Studies have shown that it can improve the prognosis of patients with advanced cirrhosis and may reduce the progression of liver failure, reduce the severity and frequency of HE and enhance survival. 

The recommendation suggests the ingestion of 1.2–1.5 g/kg(weight) daily protein in patients with compensated cirrhosis without malnutrition. While, more concentrated high-energy formulae are given in patients with ascites. Fluid restriction should only be done in cases of severe hyponatremia (Na⁺ <120 mEq/mL) and is not indicated in compensated liver disease. Carbohydrates are the foundation of the diet of cirrhotic patients and include 50–60% of non-proteic daily needs. An energy content of 35–40 kcal/kg(weight)/day is usually sufficient to maintain nutritional status and promote liver regeneration. 

 In regard to mineral supplementation, thiamine intake can be considered in all patients, especially in those who have alcoholic disease. Fat-soluble vitamins supplementation are recommended in cholestatic disease. The supplementation of zinc and magnesium can indirectly improve food intake and nutritional status improving dysgeusia. Moreover, calcium (1–1.2 g/day) and vitamin D (400–800 UI/day) supplementation is preferred especially in cholestatic disease and in patients with osteopenia. 

Source: Silva M, Gomes S, Peixoto A, et al. Nutrition in Chronic Liver Disease. GE Port J Gastroenterol. 2015;22(6):268-276. Published 2015 Aug 31.