Table 3.

Results of evidence quality for all outcomes classified by GRADE

Level of evidence	Outcomes
	Increased risk of	Increase	Decreased risk of	Reduce	No association with
High	–		–		–
Moderate	Chronic cholecystitis and cholelithiasis,27 gestational diabetes mellitus,72 gastric cancer12 and systemic sclerosis69	Triglyceride level54	Inflammatory bowel disease17	–	Stillbirth72
Low	Hepatocellular carcinoma,13 biliary lithiasis,73 peptic ulcer disease,10 chronic hepatitis C,60 non-alcoholic fatty liver disease,63 diabetic neuropathy,55 Parkinson’s disease,50 hyperemesis gravidarum,45 fetal growth restriction,72 spontaneous abortion,72 birth defect,72 open-angle glaucoma,71 autoimmune thyroid diseases,67 Grave’s disease,67 Hashimoto’s thyroiditis,67 Henoch-Schonlein purpura,64 colorectal adenomatous polyp,58 Sjogren’s syndrome,29 duodenal ulcer,12 laryngeal carcinoma,74 chronic obstructive pulmonary disease,57 diabetic nephropathy,56 gastric ulcer,12 alcoholic cirrhosis in Europian,33 cerebral ischaemia47	Ammonia levels in patients with cirrhosis37	Oesophageal adenocarcinoma in the overall population,18 eosinophilic oesophagitis,49 oesophageal eosinophilia,49 atopy53	–	Diabetic ischemic heart disease, 55 fasting blood glucose54 and diabetic ischaemic heart disease56
Very low	Lung cancer,44 cholangiocarcinoma,14 chronic tonsillitis,36 colorectal cancer, colon neoplasia,28 ischaemic heart disease,47 myocardial infarction,15 coronary heart disease,48 arrhythmia,65 chronic bronchitis,57 metabolic syndrome,54 diabetes mellitus,39 type 2 diabetes mellitus,39 chronic atrophic gastritis,11 dyspepsia,9 chronic hepatitis B,59 ischaemic stroke,61 dementia,51 pre-eclampsia,72 iron deficiency anaemia,35 iron deficiency,31 anaemia,26 migraine,52 recurrent aphthous stomatitis,40 chronic urticaria,34 halitosis,31 rosacea38 and psoriasis68	Carotid intima thickness,76 body mass index54 and homeostatic model assessment of insulin resistance54	Oesophageal squamous cell carcinoma in Eastern populations,18 Barrett’s oesophagus,32 asthma,16 end-stage renal disease in adult,62 multiple sclerosis66 and gastro-oesophageal reflux disease30	High-density lipoprotein cholesterol,54 circulating ghrelin levels46	Oesophagogastric junction adenocarcinoma,42 pancreatic cancer,41 systolic blood prssure,54 atherosclerosis,43 type 1 diabetes mellitus,39 alcoholic cirrhosis in all populations,28 stroke,70 low birth weight,72 premature delivery72 and diabetic retinopathy70