Metabolic and nutritional triggers associated with increased risk of liver complications in SARS-CoV-2

Table 1 Nutritional recommendations for patients suffering with chronic hepatic disease[44,45,95]

Nutrients	ESPEN 2019	ESPEN 2020		Critical care medicine 2020
		Non-obese	Obese
Calories	30 kcal/kg per day to 35 kcal/kg per day	30 kcal/kg per day to 35 kcal/kg per day	25 kcal/kg per day	30 kcal/kg per day to 35 kcal/kg per day; Glycaemic target at 110 mg/dL to 180 mg/dL
Protein	1.2 g/kg per day to 1.5 g/kg per day	1.2 g/kg per day to 1.5 g/kg per day	2.0 g/kg per day to 2.5 g/kg per day	1.5 g/kg per day to 2.0 g/kg per day
EN + BCAA	0.20 g/kg to 0.25 g/kg	Not routinely recommended		0.2 g/kg to 0.25 g/kg

BCAA: Branched chain amino acids; EN: Enteral nutrition.

Table 2 Vitamins, nutraceuticals and bioactive compounds in supporting therapies for coronaviruses, including severe acute respiratory syndrome coronavirus, Middle East respiratory syndrome coronavirus, bovine and avian coronavirus[107]

Nutrients and bioactive compounds (RDA, when available)	Effects in humans1	Dose	Antiviral action	Ref.
Vitamin A, 2RDA: 700-900 μg/d, UL: 3000 μg/d or 10.000 IU	Yes (Measles, Ebola)	Until 3000 IU μg/d (children from 6 mo to 11 mo) and 60000 μg/d children 1-5 yr; Adults: 60000 μg in 2 consecutive days	Measles, Ebola, Bovine coronavirus	Mayo-Wilson et al[96], 2011; Aluisio et al[97], 2019; Jee et al[72], 2013
Vitamin B2, 2RDA: 1.1-1.3 mg/d, UL: ND (not determined)	No	2-3 times RDA3	MERS-CoV + UV radiation (antiseptic)	Keil et al[73], 2016
Vitamin B12, 2RDA: 2,4 μg/d, UL: ND	Yes	5000 μg IM (intramuscular) monthly	SARS-CoV-2 (molecular modelling), HCV	Kandeel et al[76], 2020; Rocco et al[77], 2013
Vitamin C, 2RDA: 75-90 mg/d, UL: 2000 mg/d	Yes (ICU, pneumonia)	1-3 g/d; Inpatient: 50 mg/kg IV (intravenous) 6/6 h for 4 d; Elderly: 200 mg/d-2 g/d	Pneumonia, MERS-CoV	Hemilä[78], 2003; Field et al[79], 2002; Myint et al[80], 2019; International Society for Immunonutrition[98]
Vitamin D, 2RDA: 5-15 μg/d, UL: 50 μg/d or 2000 UI	Yes (pneumonia, acute upper respiratory infection)	30 μg/d; Or Bolus: 2500-5000 μg/mo; Elderly: 10-100μg/d	Pneumonia, UAI, bovine coronavirus	Martineau et al[65], 2017; Jayawardena et al[67], 2020; Grant et al[81], 2020; International Society for Immunonutrition[98]
Vitamin E, 2RDA: 15 mg/d, UL: 1000 mg/d or 1490 UI	No	300 mg 2xd for 3 mo or 365 mg/d for 6 mo; Elderly: (134- 800 mg/d)	Bovine coronavirus, Coxsackie	Andreone et al[99], 2001; Look et al[100], 1999; Nonnecke et al[83], 2014; International Society for Immunonutrition[98]
Zinc, 2RDA: 8-11 mg/d, UL: 40 mg/d	Yes (measles, SARS-CoV)	75-100 mg/d; Elderly: 30-220 mg/d	Measles, SARS-CoV	Awotiwon et al[92], 2017; te Velthuis et al[91], 2010; International Society for Immunonutrition[98]
Selenium, 2RDA: 55 μg/d, UL: 400 μg/d	Yes (influenza)	200 μg/d	Influenza, Avian coronavirus	Hoffmann and Berry[86], 2008; Ma et al[85], 2019
Omega-3	Yes (influenza)	1-3 g/d3	Influenza, HCV	Cai et al[66], 2018
Quercetin	No	1 g/d	SARS-Cov (in vitro), IVAS	Chen et al[101], 2006; Heinz et al[102], 2010
Green tea/catechins (EGCG)	No	4 cups/d or 225 mg de EGCG4	Bovine coronavirus (in vitro)	Clark et al[103], 1998
Resveratrol	No	100-150 mg 2 × d3	MERS-CoV (in vitro)	Lin et al[104], 2017
Curcumin	No	0.5-1 g/d3	SARS-CoV(in vitro)	Wen et al[105], 2007
Lipoic acid	No	600 mg/d3	Human coronavirus 229E (in vitro)	Wu et al[106], 2008

¹We did not find any work related to this substance and anti-viral or anti-infectious action in humans.

²For adult patients, according to age group and gender.

³Usual dose employed in clinical practice.

⁴Epigallocatechin.

RDA: Recommended dietary allowance; UAI: Upper airway infection; UL: Tolerable upper intake levels; ICU: Intensive care unit.